ENC624J600 DATA SHEET (01/27/2010) DOWNLOAD

ENC424J600/624J600
Data Sheet
Stand-Alone 10/100 Ethernet Controller
with SPI or Parallel Interface
 2010 Microchip Technology Inc.
DS39935C
Note the following details of the code protection feature on Microchip devices:
•
Microchip products meet the specification contained in their particular Microchip Data Sheet.
•
Microchip believes that its family of products is one of the most secure families of its kind on the market today, when used in the
intended manner and under normal conditions.
•
There are dishonest and possibly illegal methods used to breach the code protection feature. All of these methods, to our
knowledge, require using the Microchip products in a manner outside the operating specifications contained in Microchip’s Data
Sheets. Most likely, the person doing so is engaged in theft of intellectual property.
•
Microchip is willing to work with the customer who is concerned about the integrity of their code.
•
Neither Microchip nor any other semiconductor manufacturer can guarantee the security of their code. Code protection does not
mean that we are guaranteeing the product as “unbreakable.”
Code protection is constantly evolving. We at Microchip are committed to continuously improving the code protection features of our
products. Attempts to break Microchip’s code protection feature may be a violation of the Digital Millennium Copyright Act. If such acts
allow unauthorized access to your software or other copyrighted work, you may have a right to sue for relief under that Act.
Information contained in this publication regarding device
applications and the like is provided only for your convenience
and may be superseded by updates. It is your responsibility to
ensure that your application meets with your specifications.
MICROCHIP MAKES NO REPRESENTATIONS OR
WARRANTIES OF ANY KIND WHETHER EXPRESS OR
IMPLIED, WRITTEN OR ORAL, STATUTORY OR
OTHERWISE, RELATED TO THE INFORMATION,
INCLUDING BUT NOT LIMITED TO ITS CONDITION,
QUALITY, PERFORMANCE, MERCHANTABILITY OR
FITNESS FOR PURPOSE. Microchip disclaims all liability
arising from this information and its use. Use of Microchip
devices in life support and/or safety applications is entirely at
the buyer’s risk, and the buyer agrees to defend, indemnify and
hold harmless Microchip from any and all damages, claims,
suits, or expenses resulting from such use. No licenses are
conveyed, implicitly or otherwise, under any Microchip
intellectual property rights.
Trademarks
The Microchip name and logo, the Microchip logo, dsPIC,
KEELOQ, KEELOQ logo, MPLAB, PIC, PICmicro, PICSTART,
rfPIC and UNI/O are registered trademarks of Microchip
Technology Incorporated in the U.S.A. and other countries.
FilterLab, Hampshire, HI-TECH C, Linear Active Thermistor,
MXDEV, MXLAB, SEEVAL and The Embedded Control
Solutions Company are registered trademarks of Microchip
Technology Incorporated in the U.S.A.
Analog-for-the-Digital Age, Application Maestro, CodeGuard,
dsPICDEM, dsPICDEM.net, dsPICworks, dsSPEAK, ECAN,
ECONOMONITOR, FanSense, HI-TIDE, In-Circuit Serial
Programming, ICSP, Mindi, MiWi, MPASM, MPLAB Certified
logo, MPLIB, MPLINK, mTouch, Octopus, Omniscient Code
Generation, PICC, PICC-18, PICDEM, PICDEM.net, PICkit,
PICtail, PIC32 logo, REAL ICE, rfLAB, Select Mode, Total
Endurance, TSHARC, UniWinDriver, WiperLock and ZENA
are trademarks of Microchip Technology Incorporated in the
U.S.A. and other countries.
SQTP is a service mark of Microchip Technology Incorporated
in the U.S.A.
All other trademarks mentioned herein are property of their
respective companies.
© 2010, Microchip Technology Incorporated, Printed in the
U.S.A., All Rights Reserved.
Printed on recycled paper.
Microchip received ISO/TS-16949:2002 certification for its worldwide
headquarters, design and wafer fabrication facilities in Chandler and
Tempe, Arizona; Gresham, Oregon and design centers in California
and India. The Company’s quality system processes and procedures
are for its PIC® MCUs and dsPIC® DSCs, KEELOQ® code hopping
devices, Serial EEPROMs, microperipherals, nonvolatile memory and
analog products. In addition, Microchip’s quality system for the design
and manufacture of development systems is ISO 9001:2000 certified.
DS39935C-page ii
 2010 Microchip Technology Inc.
ENC424J600/624J600
Stand-Alone 10/100 Ethernet Controller
with SPI or Parallel Interface
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
IEEE 802.3™ Compliant Fast Ethernet Controller
Integrated MAC and 10/100Base-T PHY
Hardware Security Acceleration Engines
24-Kbyte Transmit/Receive Packet Buffer SRAM
Supports one 10/100Base-T Port with Automatic
Polarity Detection and Correction
Supports Auto-Negotiation
Support for Pause Control Frames, including
Automatic Transmit and Receive Flow Control
Supports Half and Full-Duplex Operation
Programmable Automatic Retransmit on Collision
Programmable Padding and CRC Generation
Programmable Automatic Rejection of Erroneous
and Runt Packets
Factory Preprogrammed Unique MAC Address
MAC:
- Support for Unicast, Multicast and Broadcast
packets
- Supports promiscuous reception
- Programmable pattern matching
- Programmable filtering on multiple packet
formats, including Magic Packet™, Unicast,
Multicast, Broadcast, specific packet match,
destination address hash match or any packet
PHY:
- Wave shaping output filter
- Internal Loopback mode
- Energy Detect Power-Down mode
Available MCU Interfaces:
- 14 Mbit/s SPI interface with enhanced set of
opcodes (44-pin and 64-pin packages)
- 8-bit multiplexed parallel interface
(44-pin and 64-pin packages)
- 8-bit or 16-bit multiplexed or demultiplexed
parallel interface (64-pin package only)
• Security Engines:
- High-performance, modular exponentiation
engine with up to 1024-bit operands
- Supports RSA® and Diffie-Hellman key
exchange algorithms
- High-performance AES encrypt/decrypt
engine with 128-bit, 192-bit or 256-bit key
- Hardware AES ECB, CBC, CFB and OFB
mode capability
- Software AES CTR mode capability
- Fast MD5 hash computations
- Fast SHA-1 hash computations
• Buffer:
- Configurable transmit/receive buffer size
- Hardware-managed circular receive FIFO
- 8-bit or 16-bit random and sequential access
- High-performance internal DMA for fast
memory copying
- High-performance hardware IP checksum
calculations
- Accessible in low-power modes
- Space can be reserved for general purpose
application usage in addition to transmit and
receive packets
• Operational:
- Outputs for two LED indicators with support
for single and dual LED configurations
- Transmit and receive interrupts
- 25 MHz clock
- 5V tolerant inputs
- Clock out pin with programmable frequencies
from 50 kHz to 33.3 MHz
- Operating voltage range of 3.0V to 3.6V
- Temperature range: -40°C to +85°C industrial
• Available in 44-Pin (TQFP and QFN) and 64-Pin
TQFP Packages
Security
8-Bit
16-Bit
Demultiplexed
SRAM
(bytes)
16-Bit
Multiplexed
Device
8-Bit
Pin
Speed
Count (Mbps)
PSP
ENC424J600
24K
44
10/100
Y
Y
Y
Y
Y
N
N
N
ENC624J600
24K
64
10/100
Y
Y
Y
Y
Y
Y
Y
Y
 2010 Microchip Technology Inc.
ModEx
MD5
AES
1024-Bit SHA-1 256-Bit
SPI
DS39935C-page 1
ENC424J600/624J600
Pin Diagrams
VSS
PSPCFG0
AD14
AD13
AD12
AD11
AD10
AD9
AD8
INT/SPISEL
CLKOUT
44-Pin TQFP and QFN
33 32 31 30 29 28 27 26 25 24 23
CS/CS
SO/WR/EN
SI/RD/RW
SCK/AL
AD0
AD1
AD2
AD3
VSS
VCAP
VDD
34
35
36
37
38
39
40
41
42
43
44
ENC424J600
22
21
20
19
18
17
16
15
14
13
12
VSSTX
TPOUTTPOUT+
VSSTX
VDDTX
TPINTPIN+
VDDRX
VSSRX
VSSPLL
VDDPLL
VSSOSC
OSC2
OSC1
VDDOSC
AD4
AD5
AD6
AD7
LEDB
LEDA
RBIAS
1 2 3 4 5 6 7 8 9 10 11
DS39935C-page 2
 2010 Microchip Technology Inc.
ENC424J600/624J600
Pin Diagrams (Continued)
CLKOUT
INT/SPISEL
AD8
AD9
AD10
AD11
AD12
AD13
AD14
AD15
A12
A14/PSPCFG1
A13
VSS
VDD
WRH/B1SEL
64-Pin TQFP
48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33
CS/CS
SO/WR/WRL/EN/B0SEL
49
32
VSSTX
50
31
TPOUT-
SI/RD/RW
51
30
TPOUT+
SCK/AL/PSPCFG4
AD0
52
29
53
28
AD1
AD2
54
27
VSSTX
VDDTX
TPIN-
55
26
TPIN+
AD3
56
25
A0
57
A1
A2
A3
58
23
VDDRX
VSSRX
VSSPLL
59
22
VDDPLL
60
21
VDD
A4
VSS
61
20
62
19
A11
A10
VCAP
VDD
63
18
64
17
 2010 Microchip Technology Inc.
AD7
RBIAS
AD6
LEDA
AD5
PSPCFG3
PSPCFG2
9 10 11 12 13 14 15 16
LEDB
8
A9
7
24
A8
6
A7
5
A6
4
AD4
2
A5
3
VDDOSC
VSSOSC
1
OSC2
OSC1
ENC624J600
DS39935C-page 3
ENC424J600/624J600
Table of Contents
1.0 Device Overview .......................................................................................................................................................................... 5
2.0 External Connections ................................................................................................................................................................... 9
3.0 Memory Organization ................................................................................................................................................................. 17
4.0 Serial Peripheral Interface (SPI)................................................................................................................................................. 39
5.0 Parallel Slave Port Interface (PSP) ............................................................................................................................................ 51
6.0 Ethernet Overview ...................................................................................................................................................................... 71
7.0 Reset .......................................................................................................................................................................................... 73
8.0 Initialization................................................................................................................................................................................. 75
9.0 Transmitting and Receiving Packets .......................................................................................................................................... 83
10.0 Receive Filters............................................................................................................................................................................ 95
11.0 Flow Control ............................................................................................................................................................................. 105
12.0 Speed/Duplex Configuration and Auto-Negotiation.................................................................................................................. 109
13.0 Interrupts .................................................................................................................................................................................. 117
14.0 Direct Memory Access (DMA) Controller ................................................................................................................................. 123
15.0 Cryptographic Security Engines ............................................................................................................................................... 125
16.0 Power-Saving Features ............................................................................................................................................................ 137
17.0 Electrical Characteristics .......................................................................................................................................................... 141
18.0 Packaging Information.............................................................................................................................................................. 149
Appendix A: Revision History............................................................................................................................................................. 157
Index .................................................................................................................................................................................................. 159
The Microchip Web Site ..................................................................................................................................................................... 163
Customer Change Notification Service .............................................................................................................................................. 163
Customer Support .............................................................................................................................................................................. 163
Reader Response .............................................................................................................................................................................. 164
Product Identification System............................................................................................................................................................. 165
TO OUR VALUED CUSTOMERS
It is our intention to provide our valued customers with the best documentation possible to ensure successful use of your Microchip
products. To this end, we will continue to improve our publications to better suit your needs. Our publications will be refined and
enhanced as new volumes and updates are introduced.
If you have any questions or comments regarding this publication, please contact the Marketing Communications Department via
E-mail at [email protected] or fax the Reader Response Form in the back of this data sheet to (480) 792-4150. We
welcome your feedback.
Most Current Data Sheet
To obtain the most up-to-date version of this data sheet, please register at our Worldwide Web site at:
http://www.microchip.com
You can determine the version of a data sheet by examining its literature number found on the bottom outside corner of any page.
The last character of the literature number is the version number, (e.g., DS30000A is version A of document DS30000).
Errata
An errata sheet, describing minor operational differences from the data sheet and recommended workarounds, may exist for current
devices. As device/documentation issues become known to us, we will publish an errata sheet. The errata will specify the revision
of silicon and revision of document to which it applies.
To determine if an errata sheet exists for a particular device, please check with one of the following:
• Microchip’s Worldwide Web site; http://www.microchip.com
• Your local Microchip sales office (see last page)
When contacting a sales office, please specify which device, revision of silicon and data sheet (include literature number) you are
using.
Customer Notification System
Register on our web site at www.microchip.com to receive the most current information on all of our products.
DS39935C-page 4
 2010 Microchip Technology Inc.
ENC424J600/624J600
1.0
DEVICE OVERVIEW
This document contains device-specific information for
the following devices:
• ENC424J600
• ENC624J600
Communication
with
the
microcontroller
is
implemented via the SPI or parallel interface, with data
rates ranging from 14 Mbit/s (SPI) to 160 Mbit/s
(demultiplexed, 16-bit parallel interface). Dedicated
pins are used for LED link and activity indication and for
transmit/receive/DMA interrupts.
The ENC424J600 and ENC624J600 are stand-alone,
Fast Ethernet controllers with an industry standard
Serial Peripheral Interface (SPI) or a flexible parallel
interface. They are designed to serve as an Ethernet
network interface for any microcontroller equipped with
SPI or a standard parallel port.
A generous 24-Kbyte on-chip RAM buffer is available
for TX and RX operations. It may also be used by the
host microcontroller for general purpose storage.
Communication protocols, such as TCP, can use this
memory for saving data which may need to be
retransmitted.
ENC424J600/624J600 devices meet all of the
IEEE 802.3 specifications applicable to 10Base-T and
100Base-TX Ethernet, including many optional
clauses, such as auto-negotiation. They incorporate a
number of packet filtering schemes to limit incoming
packets. They also provide an internal, 16-bit wide
DMA for fast data throughput and support for hardware
IP checksum calculations.
For easy end product manufacturability, each
ENC624J600 family device is preprogrammed with a
unique nonvolatile MAC address. In most cases, this
allows the end device to avoid a serialized
programming step.
For applications that require the security and authentication features of SSL, TLS and other protocols related
to cryptography, a block of security engines is provided.
The engines perform RSA, Diffie-Hellman, AES, MD5
and SHA-1 algorithm computations, allowing reduced
code size, faster connection establishment and
throughput, and reduced firmware development effort.
TABLE 1-1:
The only functional difference between the
ENC424J600 (44-pin) and ENC624J600 (64-pin)
devices are the number of parallel interface options
they support. These differences, along with a summary
of their common features, are provided in Table 1-1. A
general block diagram for the devices is shown in
Figure 1-1.
A list of the pin features, sorted by function, is
presented in Table 1-2.
DEVICE FEATURES FOR ENC424J600/624J600
Feature
Pin Count
Ethernet Operating Speed
Ethernet Duplex Modes
Ethernet Flow Control
Buffer Memory (bytes)
Internal Interrupt Sources
Serial Host Interface (SPI)
ENC424J600
ENC624J600
44
64
10/100 Mbps (auto-negotiate, auto-sense or manual)
Half and Full (auto-negotiate and manual)
Pause and Backpressure (auto and manual)
24K (organized as 12K word x 16)
11 (mappable to a single external interrupt flag)
Yes
Yes
Parallel Host Interface:
Operating modes
2
8
8-bit
Yes
Yes
16-bit
No
Yes
No
Yes
No
Yes
AES, 128/192/256-bit
Yes
Yes
MD5/SHA-1
Yes
Yes
Modular Exponentiation, 1024-bit
Yes
Yes
Muliplexed,
Demultiplexed, 8-bit
16-bit
Cryptographic Security Options:
Receive Filter Options
Packages
 2010 Microchip Technology Inc.
Accept or reject packets with CRC match/mismatch, runt error collect
or reject, Unicast, Not-Me Unicast, Multicast, Broadcast,
Magic Packet™, Pattern Table and Hash Table
44-Pin TQFP, QFN
64-Pin TQFP
DS39935C-page 5
ENC424J600/624J600
FIGURE 1-1:
ENC424J600/624J600 BLOCK DIAGRAM
Bus
Interface
CS/CS
SCK/AL
SI/RD/RW
m3
m0
m1
PHY
TPOUT+
DMA and
Checksum
MII
Interface
TX
TPOUT-
TPIN+
RX
TPINm2
Parallel
WR/WRL/
EN/B0SEL(1)
MAC
Crypto Cores
AD<15:0>(1)
A<14:0>(1)
RX Control
Logic
RX Filter
Common
SO
Arbiter
SPI
I/O
Interface
TX Control
Logic
Flow Control
Memory
WRH/
B1SEL(1)
Control
Registers
SRAM
24 Kbytes
MIIM
Interface
RBIAS
Host Interface
PSPCFGx(1)
SPISEL
25 MHz
Oscillator
Control Logic
INT
Note 1:
LEDA LEDB
Power-on
Reset
PLL
Voltage
Regulator
CLKOUT
VCAP
OSC1
OSC2
A<14:0>, AD15, WRL/B0SEL, WRH/B1SEL and PSPCFG<4:1> are available on 64-pin devices only. PSPCFG0 is available on 44-pin
devices only.
DS39935C-page 6
 2010 Microchip Technology Inc.
ENC424J600/624J600
TABLE 1-2:
ENC424J600/624J600 PINOUT DESCRIPTIONS
Pin Number
Pin Type
Input
Buffer
53
I/O
CMOS
39
54
I/O
CMOS
40
55
I/O
CMOS
AD3
41
56
I/O
CMOS
AD4
5
5
I/O
CMOS
AD5
6
6
I/O
CMOS
AD6
7
7
I/O
CMOS
Pin Name
44-Pin
64-Pin
AD0
38
AD1
AD2
AD7
8
8
I/O
CMOS
AD8
25
35
I/O
CMOS
AD9
26
36
I/O
CMOS
AD10
27
37
I/O
CMOS
AD11
28
38
I/O
CMOS
AD12
29
39
I/O
CMOS
AD13
30
40
I/O
CMOS
AD14
31
41
I/O
CMOS
AD15
—
42
I/O
CMOS
A0
—
57
I
CMOS
A1
—
58
I
CMOS
A2
—
59
I
CMOS
A3
—
60
I
CMOS
A4
—
61
I
CMOS
Description
PSP Multiplexed Address Input and/or Bidirectional
Data Bus
PSP Demultiplexed Address Input Bus
A5
—
9
I
CMOS
A6
—
10
I
CMOS
A7
—
11
I
CMOS
A8
—
12
I
CMOS
A9
—
13
I
CMOS
A10
—
19
I
CMOS
A11
—
20
I
CMOS
A12
—
43
I
CMOS
A13
—
44
I
CMOS
A14
—
45
I
CMOS
AL
37
52
I
CMOS
PSP Address Latch
B0SEL
—
50
I
CMOS
PSP Byte 0 Select
B1SEL
—
48
I
CMOS
CLKOUT
23
33
O
—
CS
34
49
I
CMOS
PSP Byte 1 Select
Programmable Clock Output for External Use
SPI Chip Select (active-low)
CS
34
49
I
CMOS
PSP Chip Select (active-high)
EN
35
50
I
CMOS
PSP R/W Enable strobe
INT
24
34
O
—
Interrupt Output (active-low)
LEDA
10
15
O
—
Programmable Ethernet Status/Activity LED
LEDB
9
14
O
—
Programmable Ethernet Status/Activity LED
Legend: I = Input; O = Output; P = Power; CMOS = CMOS compatible input buffer; ANA = Analog level input/output
 2010 Microchip Technology Inc.
DS39935C-page 7
ENC424J600/624J600
TABLE 1-2:
Pin Name
ENC424J600/624J600 PINOUT DESCRIPTIONS (CONTINUED)
Pin Number
Pin Type
Input
Buffer
ANA
44-Pin
64-Pin
3
3
I
OSC1
Description
25 MHz Crystal Oscillator/Clock Input
OSC2
2
2
O
—
PSPCFG0
32
—
I
CMOS
PSP Mode Select 0
PSPCFG1
—
45
I
CMOS
PSP Mode Select 1
PSPCFG2
—
17
I
CMOS
PSP Mode Select 2
PSPCFG3
—
18
I
CMOS
PSP Mode Select 3
PSPCFG4
—
52
I
CMOS
PSP Mode Select 4
RBIAS
11
16
I
ANA
RD
36
51
I
CMOS
PSP Read Strobe
RW
36
51
I
CMOS
PSP Combined Read/Write Signal
SCK
37
52
I
CMOS
SPI Serial Clock Input
SI
36
51
I
CMOS
SO
35
50
O
—
SPISEL
24
34
I
CMOS
TPIN-
17
27
I
ANA
25 MHz Crystal Oscillator Output
PHY Bias (external resistor) Connection
SPI Serial Data Input (from Master)
SPI Serial Data Out (to Master)
SPI/PSP Interface Select
Differential Ethernet Receive Minus Signal Input
TPIN+
16
26
I
ANA
TPOUT-
21
31
O
—
Differential Ethernet Transmit Minus Signal Output
Differential Ethernet Receive Plus Signal Input
TPOUT+
20
30
O
—
Differential Ethernet Transmit Plus Signal Output
VCAP
43
63
P
—
Regulator External Capacitor connection
VDD
44
21, 47,
64
P
—
Positive 3.3V Power Supply for Digital Logic
VDDOSC
4
4
P
—
Positive 3.3V Power Supply for 25 MHz Oscillator
VDDPLL
12
22
P
—
Positive 3.3V Power Supply for PHY PLL Circuitry
VDDRX
15
25
P
—
Positive 3.3V Power Supply for PHY RX Circuitry
18
28
P
—
Positive 3.3V Power Supply for PHY TX Circuitry
33, 42
46, 62
P
—
Ground Reference for Digital Logic
VDDTX
VSS
VSSOSC
1
1
P
—
Ground Reference for 25 MHz Oscillator
VSSPLL
13
23
P
—
Ground Reference for PHY PLL Circuitry
VSSRX
14
24
P
—
Ground Reference for PHY RX Circuitry
VSSTX
19, 22
29, 32
P
—
Ground Reference for PHY TX Circuitry
WR
35
50
I
CMOS
PSP Write Strobe
WRH
—
48
I
CMOS
PSP Write High Strobe
WRL
—
50
I
CMOS
PSP Write Low Strobe
Legend: I = Input; O = Output; P = Power; CMOS = CMOS compatible input buffer; ANA = Analog level input/output
DS39935C-page 8
 2010 Microchip Technology Inc.
ENC424J600/624J600
2.0
EXTERNAL CONNECTIONS
2.1
Oscillator
When clocking the device using a crystal, follow the
connections shown in Figure 2-1. When using a CMOS
clock oscillator or other external clock source, follow
Figure 2-2.
CRYSTAL OSCILLATOR
OPERATION
ENCX24J600
C1
(3)
OSC1
To Internal Logic
XTAL
RF(2)
C2(3)
EXTERNAL CLOCK
SOURCE
ENCX24J600
ENC424J600/624J600 devices are designed to
operate from a fixed 25 MHz clock input. This clock can
be generated by an external CMOS clock oscillator or
a parallel resonant, fundamental mode 25 MHz crystal
attached to the OSC1 and OSC2 pins. Use of a crystal,
rated for series resonant operation, will oscillate at an
incorrect frequency. To comply with IEEE 802.3 Ethernet
timing requirements, the clock must have no more than
±50 ppm of total error; avoid using resonators or clock
generators that exceed this margin.
FIGURE 2-1:
FIGURE 2-2:
RS(1)
OSC2
Note 1:
A series resistor, RS, may be required for
crystals with a low drive strength specification
or when using large loading capacitors.
2:
The feedback resistor, RF , is typically 1.5 M
approx.
3:
The load capacitors’ value should be derived
from the capacitive loading specification
provided by the crystal manufacture.
 2010 Microchip Technology Inc.
3.3V Clock from
External System(1)
OSC1
Open
OSC2
Note 1:
2.2
Duty cycle restrictions must be observed.
CLKOUT Pin
The Clock Out pin (CLKOUT) is provided for use as the
host controller clock or as a clock source for other
devices in the system. Its use is optional.
The 25 MHz clock applied to OSC1 is multiplied by a
PLL to internally generate a 100 MHz base clock. This
100 MHz clock is driven through a configurable
postscaler to yield a wide range of different CLKOUT
frequencies. The PLL multiplication adds clock jitter,
subject to the PLL jitter specification in Section 17.0
“Electrical Characteristics”. However, the postscaler
ensures that the clock will have a nearly ideal duty
cycle.
The CLKOUT function is enabled and the postscaler is
selected via the COCON<3:0> bits (ECON2<11:8>).
To create a clean clock signal, the CLKOUT output and
COCON bits are unaffected by all resets and
power-down modes. The CLKOUT function is enabled
out of POR and defaults to producing a 4 MHz clock.
This allows the device to directly clock the host
processor.
When the COCON bits are written with a new
configuration, the CLKOUT output transitions to the
new frequency without producing any glitches. No high
or low pulses with a shorter period than the original or
new clock are generated.
DS39935C-page 9
ENC424J600/624J600
2.3
2.3.1
Voltage and Bias Pin
FIGURE 2-3:
VDD AND VSS PINS
3.3V
To reduce on-die noise levels and provide for the
high-current demands of Ethernet, there are many
power pins on ENC424J600/624J600 devices:
•
•
•
•
•
VDD and VSS
VDDOSC and VSSOSC
VDDPLL and VSSPLL
VDDRX and VSSRX
VDDTX and VSSTX
Each VDD and VSS pin pair above should have a 0.1 F
ceramic bypass capacitor placed as close to the pins as
possible. For best EMI emission suppression, other
smaller capacitors, such as 0.001 F, should be placed
immediately across VDDTX/VSSTX and VDDPLL/VSSPLL.
All VDD power supply pins must be externally connected to the same 3.3V ±10% power source. Similarly,
all VSS supply references must be externally connected
to the same ground node. If a ground connection
appears on two pins (e.g., VSSTX), connect both pins;
do not allow either to float. In addition, it is
recommended that the exposed bottom metal pad on
the 44-pin QFN package be tied to VSS.
Placing ferrite beads or inductors between any two of
the supply pins (e.g., between VDDOSC and VDDRX) is
not recommended. However, it is acceptable to isolate
all of the VDD supplies from the main circuit power supply through a single ferrite bead or inductor, if desired
for supply noise suppression reasons. Such isolation is
generally not necessary.
2.3.2
VCAP PIN
Most of the device’s digital logic operates at a nominal
1.8V. This voltage is supplied by an on-chip voltage
regulator, which generates the digital supply voltage
from the VDD rail. The only external component
required is an external filter capacitor, connected from
the VCAP pin to ground, as shown in Figure 2-3. A value
of at least 10 F is recommended.
VCAP CONNECTIONS
ENCX24J600
+3.3V
VDD
I/O, PHY
Regulator
VCAP
0.1 F
10 F
2.3.3
+1.8V
Core, RAM,
MAC
VSS
RBIAS PIN
The internal analog circuitry in the PHY module
requires that an external 12.4 kΩ, 1% resistor be
attached from RBIAS to ground, as shown in
Figure 2-4. The resistor influences the TPOUT+/signal amplitude. The RBIAS resistor should be placed
as close as possible to the chip with no immediately
adjacent signal traces in order to prevent noise
capacitively coupling into the pin and affecting the
transmit behavior. It is recommended that the resistor
be a surface mount type.
FIGURE 2-4:
RBIAS RESISTOR
ENCX24J600
PHY
RBIAS
12.4k1%
The capacitor must also have a relatively low Equivalent Series Resistance (ESR). It is recommended that
a low-ESR capacitor (ceramic, tantalum or similar)
should be used and high-ESR capacitors (such as
aluminum electrolytic) should be avoided.
The internal regulator is not designed to drive external
loads; therefore, do not attach other circuitry to VCAP.
DS39935C-page 10
 2010 Microchip Technology Inc.
ENC424J600/624J600
2.4
Ethernet Signal Pins and External
Magnetics
Typical applications for ENC424J600/624J600 devices
require an Ethernet transformer module, and a few
resistors and capacitors to implement a complete
IEEE 802.3 compliant 10/100 Ethernet interface, as
shown in Figure 2-5.
The Ethernet transmit interface consists of two pins:
TPOUT+ and TPOUT-. These pins implement a
differential pair and a current-mode transmitter. To
generate an Ethernet waveform, ordinary applications
require the use of a 1:1 center tapped pulse
transformer, rated for 10/100 or 10/100/1000 Ethernet
operations. When the Ethernet module is enabled and
linked with a partner, current is continually sunk
through both TPOUT pins. When the PHY is actively
transmitting, a differential voltage is created on the
Ethernet cable by varying the relative current sunk by
TPOUT+ compared to TPOUT-.
The Ethernet receive interface similarly consists of a
differential pair: TPIN+ and TPIN-. To meet IEEE 802.3
compliance and help protect against electrostatic discharge, these pins are normally isolated from the
Ethernet cable by a 1:1 center tapped transformer
(available in the same package as the TX transformer).
Internally, the PHY uses a high-speed ADC to sample
the receive waveform and decodes it using a DSP. The
PHY implements many robustness features, including
FIGURE 2-5:
baseline wander correction (applicable to 100Base-TX)
and automatic RX polarity correction (applicable to
10Base-T).
Four 49.9Ω, 1% resistors are required for proper
termination of the TX and RX transmission lines. If the
board layout necessitates long traces between the
ENCX24J600 and Ethernet transformers, the termination resistors should be placed next to the silicon
instead of the transformers.
On the receive signal path, two 6.8 nF 10% capacitors
are used. These capacitors, in combination with the
49.9 termination resistors, form an RC high-pass filter
to reduce baseline wander. For best performance,
these capacitors should not be omitted or changed.
The various remaining capacitors provide DC current
blocking and provide stability to the common-mode
voltage of both of the differential pairs. The TPIN+/pins weakly output a common-mode voltage that is
acceptable to the internal ADC. For proper operation,
do not attempt to externally force the TPIN+/common-mode voltage to some other value.
The 10Ω 1% resistor provides a current path from the
power supply to the center tap of the TX transformer.
As mentioned previously, the TPOUT+/- pins
implement a Current mode drive topology in which the
pins are only capable of sinking current; they do not
produce a direct voltage. This current path through the
transformer generates the transmit waveform. The 10Ω
resistor reduces the amount of heat that the PHY would
have to dissipate, and therefore, must have a power
rating of 1/12W or better.
TYPICAL ETHERNET MAGNETICS CONNECTIONS
3.3V
1
10, 1/12W, 1%
ENCX24J600
RJ-45
TPOUT+
1
49.9, 1%
49.9, 1%
TPOUT-
6.8 nF, 10%
TPIN+
2
0.01 F
3
1:1 CT
4
49.9, 1%
49.9, 1%
TPIN-
5
6.8 nF, 10%
1:1 CT
6
7
0.01 F
8
75
75
75
75
1000 pF, 2 kV
 2010 Microchip Technology Inc.
DS39935C-page 11
ENC424J600/624J600
2.4.1
ADDITIONAL EMI AND LAYOUT
CONSIDERATIONS
To reduce EMI emissions, common-mode chokes are
shown adjacent to the transformers on the cable
(RJ-45) side. These chokes come standard in typical
Ethernet transformer modules. Because the
ENCX24J600 PHY uses a current-mode drive topology, the transmit choke must normally be located on
the cable side of the transmit transformer. Orienting the
magnetics such that the choke is on the PHY side of the
transmit transformer usually results in a distorted,
non-compliant transmit waveform. However, some
magnetics which wrap the TX center tap wire around
the TX choke core can also be used to generate a
compliant waveform (Figure 2-6). These types of transformers may be desirable in some Power-over Ethernet
(PoE) applications.
FIGURE 2-6:
By default on POR, LEDA displays the Ethernet link
status, while LEDB displays PHY-level TX/RX activity.
Because the LEDs operate at the PHY level, RX
activity will be displayed on LEDB any time Ethernet
packets are detected, regardless of if the packet is valid
and meets the correct RX filtering criteria.
Normally, the device illuminates the LED by sourcing
current out of the pin, as shown in Figure 2-7. Connecting the LED in reverse, with the anode connected to
VDD and the cathode to LEDA/LEDB (through a
current-limiting resistor), causes the LED to show
“inverted sense” behavior, lighting the LED when it
should be off and extinguishing the LED when the LED
should be on.
FIGURE 2-7:
ALTERNATE TX CHOKE
TOPOLOGY
PHY
LEDA
or
LEDB
SINGLE COLOR LED
CONNECTION
180
LED
RJ-45
1:1 CT
The common-mode choke on the RX interface can be
placed on either the cable side or PHY side of the
receive transformer. Recommended and required magnetics characteristics are located in Section 17.0
“Electrical Characteristics”.
Both LEDs automatically begin operation whenever
power is applied, a 25 MHz clock is present and the
Ethernet magnetics are present and wired correctly. A
connection to the host microcontroller via the SPI or
PSP interface is not required. LEDA and LEDB can,
therefore, be used as a quick indicator of successful
assembly during initial prototype development.
2.5.1
USING BI-COLOR LEDs
The four 75Ω resistors and high-voltage capacitor in
Figure 2-5 are intended to prevent each of the twisted
pairs in the Ethernet cables from floating and radiating
EMI. Their implementation may require adjustment in
PoE applications.
In space constrained applications, it is frequently desirable to use a single bi-color LED to display multiple
operating parameters. These LEDs are connected
between LEDA and LEDB, as shown in Figure 2-8.
Unless the TX and RX signal pairs are kept short, they
should be routed between the ENCX24J600 and the
Ethernet connector following differential routing rules.
Like Ethernet cables, 100Ω characteristic impedance
should be targeted for the differential traces. The use of
vias, which introduce impedance discontinuities,
should be minimized. Other board level signals should
not run immediately parallel to the TX and RX pairs to
minimize capacitive coupling and crosstalk.
FIGURE 2-8:
2.5
LEDA and LEDB Pins
The LEDA and LEDB pins provide dedicated LED
status indicator outputs. The LEDs are intended to
display link status and TX/RX activity among other
programmable options; however, the use of one or both
is entirely optional. The pins are driven automatically by
the hardware and require no support from the host
microcontroller. Aside from the LEDs themselves, a
current-limiting resistor is generally the only required
component.
DS39935C-page 12
LEDA
BI-COLOR LED
CONNECTION
180
Bi-Color
LED
LEDB
ENCX24J600 devices include two special hardware
display modes to make maximal use of a bi-color LED.
These modes are selected when the LACFG<3:0> and
LBCFG<3:0> bits (EIDLED<15:8>) are set to ‘1111’ or
‘1110’. In these configurations, the link state turns the
LED on, the speed/duplex state sets the LED color and
TX/RX events cause the LED to blink off. If a link is
present, no TX/RX events are occurring and the
speed/duplex state is 100 Mbps/full duplex,
respectively, then the LEDB pin will be driven high while
LEDA will be driven low.
 2010 Microchip Technology Inc.
ENC424J600/624J600
2.6
INT Pin
The INT pin is an active-low signal that is used to flag
interrupt events to external devices. Depending on the
application, it can be used to signal the host microcontroller whenever a packet has been received or
transmitted, or that some other asynchronous
operation has occurred. It can also be used to wake-up
the microcontroller or other system components based
on LAN activity; its use is optional.
The INT pin is driven high when no interrupt is pending
and is driven low when an interrupt has occurred. It
does not go into a high-impedance state, except during
initial power-on while the multiplexed SPISEL pin
function is being used.
Since ENC424J600/624J600 devices incorporate a
buffer for storing transmit and receive packets, the host
microcontroller never needs to perform real-time
operations on the device. The microcontroller can poll
the device registers to discover if the device status has
changed.
2.7
Host Interface Pins
For the maximum degree of flexibility in interfacing with
microcontrollers, ENC424J600/624J600 devices offer
a choice between a serial interface based on the Serial
Peripheral Interface (SPI) standard, and a flexible 8 or
16-bit parallel slave port (PSP) interface. Only one
interface may be used at any given time.
The I/O interface is hardware selected on power-up
using the SPISEL function on the INT/SPISEL pin. This
is done by latching in the voltage level applied to the pin
FIGURE 2-9:
To ensure the SPI interface is selected upon power-up,
an external pull-up resistor to VDD must be connected
to the SPISEL pin. Alternatively, if the parallel interface
is to be used, a pull-down resistor to VSS must be
connected to the SPISEL pin. In most circuits, it is recommended that a 100 kΩ or smaller resistor be used to
ensure that the correct logic level is latched in reliably.
If a large capacitance is present in the SPISEL circuit,
such as from stray capacitance, a smaller pull-up or
pull-down resistor may be required to compensate and
ensure the correct level is sensed during power-up.
As SPISEL is multiplexed with the INT interrupt output
function, a direct connection to VDD or VSS without a
resistor is prohibited. If INT is connected to the host
microcontroller, the microcontroller must leave this
signal in a high-impedance state and not attempt to
drive it to an incorrect logic state during power-up.
If the VDD supply has a slow ramp rate, the device will
exit POR, exceed the 1 to 10 s latch timer and sample
the SPISEL pin state before VDD has reached the specified minimum operating voltage of the device. In this
case, the device will still latch in the correct value,
assuming the minimum VIH (D004) or maximum VIL
(D006) specification is met, which is a function of VDD.
USING THE INT/SPISEL PIN TO SELECT THE I/O INTERFACE
3.3V
MCU
approximately 1 to 10 s after power is applied to the
device and the device exits Power-on Reset. If SPISEL
is latched at a logic high state, the serial interface is
enabled. If SPISEL is latched at a logic low state, the
PSP interface is enabled. Figure 2-9 shows example
connections required to select the SPI or PSP interface
upon power-up.
ENCX24J600
~2.2V
100k
INT0
I/O
SCK
SDO
SDI
INT/SPISEL
CS
ENCX24J600
MCU
PMALL
AL
PMCS2
CS
RMRD
RD
PMWR
WR
PMAx/PMDx
ADx
SCK
SI
SO
VSS
INT/SPISEL
INT0
100k
SPI Selected
(internal weak pull-up on CS enabled)
 2010 Microchip Technology Inc.
PSP Selected (Mode 5 shown)
(internal weak pull-down on CS enabled)
DS39935C-page 13
ENC424J600/624J600
2.7.1
SPI
parallel interfaces; not all available pins are used in
every configuration. Up to 8 different operating modes
are available. These are explained in detail in
Section 5.0 “Parallel Slave Port Interface (PSP)”.
When enabled, the SPI interface is implemented with
four pins:
•
•
•
•
CS
SO
SI
SCK
All four of these pins must be connected to use the SPI
interface.
The PSPCFG pins control which parallel interface
mode is used. The values on these pins are latched
upon device power-up in the same manner as the
SPISEL pin. The combinations of VDD and VSS voltages on the different PSPCFG mode pins determine
the PSP mode according to Table 2-1.
The CS, SI and SCK input pins are 5V tolerant. The SO
pin is also 5V tolerant when in a high-impedance state.
SO is always high-impedance when CS is connected to
logic high (i.e., chip not selected).
On ENC424J600 devices, only PSP Modes 5 and 6
(8-bit width, multiplexed data and address) are
available. The mode is selected by applying VSS or
VDD, respectively, to PSPCFG0.
When the SPI interface is enabled, all PSP interface
pins (except PSPCFG2 and PSPCFG3 on
ENC624J600 devices) are unused. They are placed in
a high-impedance state and their input buffers are disabled. For best ESD performance, it is recommended
that the unused PSP pins be tied to either VSS or VDD.
However, these pins may be left floating if it is desirable
for board level layout and routing reasons.
On ENC624J600 devices, all eight PSP modes are
available and are selected by connecting the
PSPCFG<4:1> pins directly to VDD or ground. The
mode selection is encoded such that the multiplexed
pin functions, AD14 (on PSPCFG1) and SCK/AL (on
PSPCFG4), are used only in the “don’t care” positions.
Therefore, pull-up/pull-down resistors are not required
for these pins.
When using an ENC624J600 device in SPI mode, it is
recommended that the PSPCFG2 and PSPCFG3 pins
be tied to either VSS or any logic high voltage, and not
be left floating. The particular state used is unimportant.
All PSP pins, except for AD<15:0>, are inputs to the
ENC624J600 family device and are 5V tolerant. The
AD<15:0> pins are bidirectional I/Os and are 5V
tolerant in Input mode. The pins are always inputs
when the CS signal is low (chip not selected).
2.7.2
Any unused PSP pins are placed in a high-impedance
state. However, it is recommended that they be tied to
either Vss or a logic high voltage and not be left floating.
PSP
Depending on the particular device, the PSP interface
is implemented with up to 34 pins. The interface is
highly configurable to accommodate many different
TABLE 2-1:
Interface
Mode
PSP MODE SELECTION FOR ENC424J600/624J600 DEVICES
PSPCFG
Pins Used
INT/SPISEL
0
1
2
3
4
44-Pin
PSP Mode 5
Pull Down
0
—
—
—
—
AL, CS, RD, WR, AD<14:0>
PSP Mode 6
Pull Down
1
—
—
—
—
AL, CS, RW, EN, AD<14:0>
PSP Mode 1
Pull Down
—
x
0
0
64-Pin
0
CS, RD, WR, A14:A0, AD<7:0>
PSP Mode 2
Pull Down
—
x
0
0
1
CS, RW, EN, A14:A0, AD<7:0>
PSP Mode 3
Pull Down
—
x
1
0
0
CS, RD, WRL, WRH, A<13:0>, AD<15:0>
PSP Mode 4
Pull Down
—
x
1
0
1
CS, RW, B0SEL, B1SEL, A<13:0>, AD<15:0>
PSP Mode 5
Pull Down
—
0
0
1
x
AL, CS, RD, WR, AD<14:0>
PSP Mode 6
Pull Down
—
1
0
1
x
AL, CS, RW, EN, AD<14:0>
PSP Mode 9
Pull Down
—
0
1
1
x
AL, CS, RD, WRL, WRH, AD<15:0>
PSP Mode 10
Pull Down
—
1
1
1
x
AL, CS, RW, B0SEL, B1SEL, AD<15:0>
Legend: x = don’t care, 0 = logic low (tied to VSS), 1 = logic high (tied to VDD), — = pin not present
DS39935C-page 14
 2010 Microchip Technology Inc.
ENC424J600/624J600
2.7.3
CS/CS PIN
The chip select functions for the serial and parallel
interfaces are shared on one common pin, CS/CS. This
pin is equipped with both internal weak pull-up and
weak pull-down resistors. If the SPI interface is
selected (CS), the pull-up resistor is automatically
enabled and the pull-down resistor is disabled. If the
PSP interface is chosen (CS), the pull-down resistor is
automatically enabled and the pull-up resistor is
disabled. This allows the CS/CS pin to stay in the
unselected state when not being driven, avoiding the
need for an external board level resistor on this pin.
When enabled by using SPI mode, the internal weak
pull-up only pulls the CS/CS pin up to approximately
VDD-1.1V or around 2.2V at typical conditions without
any loading; it does not pull all the way to VDD. When
using the PSP interface, the pull-down will be enabled,
which is capable of pulling all the way to VSS when
unloaded.
2.8
FIGURE 2-10:
LEVEL SHIFTING ON THE
SPI INTERFACE USING
AND GATES
3.3V
100k
MCU
ENCX24J600
INT/SPISEL
INTx
CLKOUT
OSC1
SDI
SO
I/O
CS
SCK
SCK
SDO
SI
Digital I/O Levels
All digital output pins on ENC424J600/624J600
devices contain CMOS output drivers that are capable
of sinking and sourcing up to 18 mA continuously. All
digital inputs and I/O pins operating as inputs are 5V
tolerant. These features generally mean that the
ENCX24J600 can connect directly to the host
microcontroller without the need of any glue logic.
However, some consideration may be necessary when
interfacing with 5V systems.
Since the digital outputs drive only up to the VDD
voltage (3.3V nominally), the voltage may not be high
enough to ensure a logical high is detected by 5V
systems which have high input thresholds. In such
cases, unidirectional level translation from the 3.3V
ENCX24J600 up to the 5V host microcontroller may be
needed.
FIGURE 2-11:
LEVEL SHIFTING ON THE
SPI INTERFACE USING
3-STATE BUFFERS
3.3V
100k
MCU
INTx
OSC1
SDI
I/O
ENCX24J600
INT/SPISEL
CLKOUT
SO
CS
SCK
SCK
SDO
SI
When using the SPI interface, an economical 74HCT08
(quad AND gate), 74ACT125 (quad 3-state buffer) or
other 5V CMOS chip with TTL level input buffers may
be used to provide the necessary level shifting. The
use of 3-state buffers permits easy integration into
systems which share the SPI bus with other devices.
However, users must make certain that the propagation delay of the level translator does not reduce the
maximum SPI frequency below desired levels.
Figure 2-10 and Figure 2-11 show two example
translation schemes.
When using the PSP interface, eight, or all sixteen of
the ADx pins, may need level translation when performing read operations on the ENCX24J600. The 8-bit
74ACT245 or 16-bit 74ACT16245 bus transceiver, or
similar devices, may be useful in these situations.
 2010 Microchip Technology Inc.
DS39935C-page 15
ENC424J600/624J600
NOTES:
DS39935C-page 16
 2010 Microchip Technology Inc.
ENC424J600/624J600
3.0
MEMORY ORGANIZATION
3.1.1
SPI INTERFACE MAP
All memory in ENC424J600/624J600 devices is
implemented as volatile RAM. Functionally, there are
four unique memories:
When the SPI interface is selected, the device memory
map is comprised of three memory address spaces
(Figure ):
•
•
•
•
• the SFR area
• the main memory area
• the PHY register area
Special Function Registers (SFRs)
PHY Special Function Registers
Cryptographic Data Memory
SRAM Buffer
The SFRs configure, control and provide status
information for most of the device. They are directly
accessible through the I/O interface.
The PHY SFRs configure, control and provide status
information for the PHY module. They are located
inside the PHY module and isolated from all other
normal SFRs, so they are not directly accessible
through the I/O interface.
The cryptography data memory is used to store key
and data material for the modular exponentiation, AES
and MD5/SHA-1 hashing engines. This memory area
can only be accessed through the DMA module.
The SRAM buffer is a bulk 12K x 16-bit (24 Kbyte) RAM
array used for TX and RX packet buffering, as well as
general purpose storage by the host microcontroller.
Although the SRAM uses a 16-bit word, it is
byte-writable. This memory is indirectly accessible
through pointers on all I/O interfaces. It can also be
accessed directly through the PSP interfaces.
3.1
I/O Interface and Memory Map
Depending on the I/O interface selected, the four
memories are arranged into two or three different memory
address spaces. When the serial interface is selected, the
memories are grouped into three address spaces. When
one of the parallel interfaces is selected, they are
arranged into two address spaces. In all cases, the PHY
SFRs reside in their own memory address space.
FIGURE 3-1:
SFR Area
The SFR area is directly accessible to the user. This is
a linear memory space that is 160 bytes long. For
efficiency, the SFR area can be addressed as four
banks of 32 bytes each, starting at the beginning of the
space (00h), with an additional unbanked area of
32 bytes at the end of the SFR memory. Banked
addressing allows SFRs to be addressed with fewer
address bits being exchanged over the serial interface
for each transaction. This decreases protocol overhead
and enhances performance. SFRs can also be directly
addressed by their 8-bit unbanked addresses using
unbanked SPI commands. This allows for a simpler
interface whenever transaction overhead is not critical.
The main memory area is organized as a linear,
byte-addressable space of 32 Kbytes. Of this, the first
24-Kbyte area (0000h through 5FFFh) is implemented
as the SRAM buffer. The buffer is accessed by the
device using several SFRs as memory pointers and
virtual data window registers, as described in
Section 3.5.5 “Indirect SRAM Buffer Access”.
Addresses in the main memory area, between 7800h
and 7C4Fh, are mapped to the memory for the cryptographic data modules. These addresses are not
directly accessible through the SPI interface; they can
only be accessed through the DMA.
The PHY SFRs are the final memory space. This is a
linear, word-addressable memory space of 32 words.
This area is only accessible by the MIIM interface (see
Section 3.3 “PHY Special Function Registers” for
more details).
ENC424J600/624J600 MEMORY MAP WITH SPI INTERFACE
Unbanked Opcodes
Banked Opcodes
Bank 0
Bank 1
Bank 2
Bank 3
Unbanked
(inaccessible using
banked opcodes)
Pointers
00h 00h
1Fh 1Fh
00h 20h
SRAM Buffer
1Fh 3Fh
00h 40h
1Fh 5Fh
00h 60h
5FFFh
1Fh 7Fh
80h
Unimplemented
9Fh
Cryptographic Data
(DMA access only)
MIREGADR
PHY Register
Area
16-Bit, MIIM Access Only
 2010 Microchip Technology Inc.
0000h
Main Area
00h
1Fh
Unimplemented
7800h
7C4Fh
7FFFh
DS39935C-page 17
ENC424J600/624J600
3.1.2
PSP INTERFACE MAPS
When one of the parallel interfaces is selected, the
memory map is very different from the SPI map. There
are two different memory address spaces (Figure 3-2):
• the main memory area
• the PHY register area
As in the serial memory map, the main memory area is
a linear, byte-addressable space of 32 Kbytes, with the
SRAM buffer located in the first 24-Kbyte region. The
cryptographic data memory is also mapped to the same
location as in the serial memory map. The main difference is that the SFRs are now located to an area with a
higher address than the cryptographic data space. Additional memory areas above the SFRs are reserved for
their accompanying Bit Set and Bit Clear registers.
Except for the cryptographic data memory, all
addresses in the main memory area are directly
accessible using the PSP bus. As with the serial interface, the cryptographic memory can only be accessed
through the DMA.
The difference between the 8-bit and 16-bit interfaces is
how the SRAM buffer is addressed by the external
address bus. In 16-bit data modes, the address bus
treats the buffer as a 16-byte wide, word-addressable
space, spanning 000h to 3FFFh. In 8-bit data modes, the
address bus treats the buffer as an 8-bit, byte-addressable space, ranging from 0000h to 7FFFh. In either case,
the SFRs used as memory pointers still address the
buffer as a byte-wide, byte-addressable space.
The PHY SFR space is implemented in the same
manner as the SPI interface described above.
In both 8-bit and 16-bit PSP modes, full device functionality can be realized without using the full width of
the address bus. This is because the SRAM buffer can
still be read and written to by using SFR pointers. In
practical terms, this can allow designers in space or pin
constrained applications to only connect a subset of the
A or AD address pins to the host microcontroller. For
example, in the 8-Bit Multiplexed PSP Modes 5 or 6,
tying pins, AD<14:9> to VDD, still allows direct address
access to all SFRs. This reduces the number of pins
required for connection to the host controller, including
the interface control pins to 12 or 13.
ENC424J600/624J600 MEMORY MAPS FOR PSP INTERFACES(1)
FIGURE 3-2:
8-Bit PSP
16-Bit PSP
Main Area
Main Area
PSP Address Bus (Word Address)
Pointers (Byte Address)
PSP Address Bus and
All Pointers
0000h
0000h 0000h
SRAM Buffer
SRAM Buffer
5FFFh 2FFFh
5FFFh
Unimplemented
Unimplemented
7800h(2)
Cryptographic Data
(DMA access only)
7C4Fh(2)
Unimplemented
Special Function
Registers (R/W)
SFR Bit Set Registers
SFR Bit Clear Registers
PHY Register Area
7C4Fh(2)
Unimplemented
3F00h
7E00h
Special Function Registers (R/W)
7E9Fh
7F00h
7F7Fh
7F80h
7FFFh
SFR Bit Set Registers
SFR Bit Clear Registers
MIREGADR
16-Bit, MIIM Access Only
Note 1:
2:
7800h(2)
Cryptographic Data
(DMA access only)
00h
1Fh
PHY Register Area
3F4Fh
3F80h
3FBFh
3FC0h
3FFFh
MIREGADR
16-Bit, MIIM Access Only
00h
1Fh
Memory areas not shown to scale.
Addresses in this range are accessible only through internal address pointers of the DMA module.
DS39935C-page 18
 2010 Microchip Technology Inc.
ENC424J600/624J600
3.2
Special Function Registers
The SFRs provide the main interface between the host
controller and the on-chip Ethernet controller logic.
Writing to these registers controls the operation of the
interface, while reading the registers allows the host
controller to monitor operations.
All registers are 16 bits wide. On the SPI and 8-bit PSP
interfaces, which are inherently byte-oriented, the
registers are split into separate high and low locations
which are designated by an “H” or “L” suffix, respectively. All registers are organized in little-endian format
such that the low byte is always at the lower memory
address.
Some of the available addresses are unimplemented or
marked as reserved. These locations should not be
written to. Data read from reserved locations should be
ignored. Reading from unimplemented locations will
return ‘0’. When reading and writing to registers which
contain reserved bits, any rules stated in the register
definition should be observed.
The addresses of all user-accessible registers are
provided in Tables 3-1 through 3-6. A complete bit level
listing of the SFRs is presented in Table 3-7 (page 26).
3.2.1
E REGISTERS
SFRs with names starting with “E” are the primary
control and pointer registers. They configure and control all of the (non-MAC) top-level features of the
device, as well as manipulate the pointers that define
the memory buffers. These registers can be read and
written in any order, with any length, without concern
for address alignment.
3.2.2
3.2.3
SPI REGISTER MAP
As previously described, the SFR memory is
partitioned into four banks plus a special region that is
not bank addressable. Each bank is 32 bytes long and
addressed by a 5-bit address value. All SFR memory
may also be accessed via unbanked SPI opcodes
which use a full 8-bit address to form a linear address
map without banking.
The last 10 bytes (16h to 1Fh) of all SPI banks point to
a common set of five registers: EUDAST, EUDAND,
ESTAT, EIR and ECON1. These are key registers used
in controlling and monitoring the operation of the
device. Their common banked addresses allow easy
access without switching the bank.
The SPI interface implements a comprehensive
instruction set that allows for reading and writing of
registers, as well as setting and clearing individual bits
or bit fields within registers. The SPI instruction set is
explained in detail in Section 4.0 “Serial Peripheral
Interface (SPI)”.
The SFR map for the SPI interface is shown in
Table 3-1. Registers are presented by a bank. The
banked (5-bit) address applicable to the registers in
each row is shown in the left most column. The
unbanked (8-bit) address for each register is shown to
the immediate left of the register name.
Note:
SFRs in the unbanked region (80h through
9Fh) cannot be accessed using banked
addressing. The use of an unbanked SFR
opcode is required to perform operations
on these registers.
MAC REGISTERS
SFRs with names that start with “MA” or “MI” are
implemented in the MAC module hardware. For this
reason, their operation differs from “E” registers in two
ways.
First, MAC registers support read and write operations
only. Individual bit set and bit clear operations cannot
be performed.
Additionally, MAC registers must always be written as
a 16-bit word, regardless of the I/O interface being
used. That is, on the SPI or 8-bit PSP interfaces, all
write operations must be performed by writing to the
low byte, followed by a write to the associated high
byte. On 16-bit PSP interfaces, both write enables or
byte selects must be asserted to perform the 16-bit
write. Non-sequential writes, such as writing to the low
byte of one MAC register, the low byte of a second
MAC register and then the high byte of the first register
cannot be performed.
 2010 Microchip Technology Inc.
DS39935C-page 19
ENC424J600/624J600
TABLE 3-1:
ENC424J600/624J600 SFR MAP (SPI INTERFACE)
Bank 2
(40h offset)
Unbanked(1)
(80h offset)
Bank 3
(60h offset)
ETXSTL
01
01
ETXSTH
21
EHT1H
41
MACON1H
61
MAADR3H
81
Reserved
02
02
ETXLENL
22
EHT2L
42
MACON2L
62
MAADR2L
82
ERXDATA(2)
03
03
ETXLENH
23
EHT2H
43
MACON2H
63
MAADR2H
83
Reserved
04
04
ERXSTL
24
EHT3L
44
MABBIPGL
64
MAADR1L
84
EUDADATA(2)
20
EHT1L
40
MACON1L
Name
Unbanked
Address
00
Name
Unbanked
Address
00
Name
Unbanked
Address
Name
Unbanked
Address
Unbanked
Address
Bank 1
(20h offset)
Banked Register
Addresses
Bank 0
(00h offset)
Name
60
MAADR3L
80
EGPDATA(2)
05
05
ERXSTH
25
EHT3H
45
MABBIPGH
65
MAADR1H
85
Reserved
06
06
ERXTAILL
26
EHT4L
46
MAIPGL
66
MIWRL
86
EGPRDPTL
07
07
ERXTAILH
27
EHT4H
47
MAIPGH
67
MIWRH
87
EGPRDPTH
08
08
ERXHEADL
28
EPMM1L
48
MACLCONL
68
MIRDL
88
EGPWRPTL
EGPWRPTH
09
09
ERXHEADH
29
EPMM1H
49
MACLCONH
69
MIRDH
89
0A
0A
EDMASTL
2A
EPMM2L
4A
MAMXFLL
6A
MISTATL
8A
ERXRDPTL
0B
0B
EDMASTH
2B
EPMM2H
4B
MAMXFLH
6B
MISTATH
8B
ERXRDPTH
0C
0C
EDMALENL
2C
EPMM3L
4C
Reserved
6C
EPAUSL
8C
ERXWRPTL
0D
0D
EDMALENH
2D
EPMM3H
4D
Reserved
6D
EPAUSH
8D
ERXWRPTH
0E
0E
EDMADSTL
2E
EPMM4L
4E
Reserved
6E
ECON2L
8E
EUDARDPTL
0F
0F
EDMADSTH
2F
EPMM4H
4F
Reserved
6F
ECON2H
8F
EUDARDPTH
10
10
EDMACSL
30
EPMCSL
50
Reserved
70
ERXWML
90
EUDAWRPTL
EUDAWRPTH
11
11
EDMACSH
31
EPMCSH
51
Reserved
71
ERXWMH
91
12
12
ETXSTATL
32
EPMOL
52
MICMDL
72
EIEL
92
Reserved
13
13
ETXSTATH
33
EPMOH
53
MICMDH
73
EIEH
93
Reserved
14
14
ETXWIREL
34
ERXFCONL
54
MIREGADRL
74
EIDLEDL
94
Reserved
15
15
ETXWIREH
35
ERXFCONH
55
MIREGADRH
75
EIDLEDH
95
Reserved
16
16
EUDASTL
36
EUDASTL
56
EUDASTL
76
EUDASTL
96
Reserved
17
17
EUDASTH
37
EUDASTH
57
EUDASTH
77
EUDASTH
97
Reserved
18
18
EUDANDL
38
EUDANDL
58
EUDANDL
78
EUDANDL
98
Reserved
Reserved
19
19
EUDANDH
39
EUDANDH
59
EUDANDH
79
EUDANDH
99
1A
1A
ESTATL
3A
ESTATL
5A
ESTATL
7A
ESTATL
9A
Reserved
1B
1B
ESTATH
3B
ESTATH
5B
ESTATH
7B
ESTATH
9B
Reserved
1C
1C
EIRL
3C
EIRL
5C
EIRL
7C
EIRL
9C
Reserved
1D
1D
EIRH
3D
EIRH
5D
EIRH
7D
EIRH
9D
Reserved
1E
1E
ECON1L
3E
ECON1L
5E
ECON1L
7E
ECON1L
9E
—
1F
1F
ECON1H
3F
ECON1H
5F
ECON1H
7F
ECON1H
9F
—
Note 1:
2:
Unbanked SFRs can be accessed only by unbanked SPI opcodes.
When using these registers to access the SRAM buffer, use only the N-byte SRAM instructions. See Section 4.6.2
“Unbanked SFR Operations” and Section 4.6.3 “SRAM Buffer Operations” for more details.
DS39935C-page 20
 2010 Microchip Technology Inc.
ENC424J600/624J600
3.2.4
PSP REGISTER MAP
When using a PSP interface, the SFR memory is linear;
all registers are directly accessible without banking. To
maintain consistency with the SPI interface, the
EUDAST, EUDAND, ESTAT, EIR and ECON1 registers
are instantiated in four locations in the PSP memory
maps. Users may opt to use any one of these four
locations.
TABLE 3-2:
Addr
The SFR maps for the 8-bit and 16-bit PSP interfaces
are shown in Table 3-2 and Table 3-3, respectively.
ENC424J600/624J600 SFR MAP (BASE REGISTER MAP, 8-BIT PSP INTERFACE)
Name
Addr
Name
Addr
Name
Addr
Name
Addr
Name
EGPDATA
7E00
ETXSTL
7E20
EHT1L
7E40
MACON1L
7E60
MAADR3L
7E80
7E01
ETXSTH
7E21
EHT1H
7E41
MACON1H
7E61
MAADR3H
7E81
Reserved
7E02
ETXLENL
7E22
EHT2L
7E42
MACON2L
7E62
MAADR2L
7E82
ERXDATA
7E03
ETXLENH
7E23
EHT2H
7E43
MACON2H
7E63
MAADR2H
7E83
Reserved
EUDADATA
7E04
ERXSTL
7E24
EHT3L
7E44
MABBIPGL
7E64
MAADR1L
7E84
7E05
ERXSTH
7E25
EHT3H
7E45
MABBIPGH
7E65
MAADR1H
7E85
Reserved
7E06
ERXTAILL
7E26
EHT4L
7E46
MAIPGL
7E66
MIWRL
7E86
EGPRDPTL
7E07
ERXTAILH
7E27
EHT4H
7E47
MAIPGH
7E67
MIWRH
7E87
EGPRDPTH
7E08
ERXHEADL
7E28
EPMM1L
7E48
MACLCONL
7E68
MIRDL
7E88
EGPWRPTL
7E09
ERXHEADH
7E29
EPMM1H
7E49
MACLCONH
7E69
MIRDH
7E89
EGPWRPTH
7E0A
EDMASTL
7E2A
EPMM2L
7E4A
MAMXFLL
7E6A
MISTATL
7E8A
ERXRDPTL
7E0B
EDMASTH
7E2B
EPMM2H
7E4B
MAMXFLH
7E6B
MISTATH
7E8B
ERXRDPTH
7E0C
EDMALENL
7E2C
EPMM3L
7E4C
Reserved
7E6C
EPAUSL
7E8C
ERXWRPTL
7E0D
EDMALENH
7E2D
EPMM3H
7E4D
Reserved
7E6D
EPAUSH
7E8D
ERXWRPTH
7E0E
EDMADSTL
7E2E
EPMM4L
7E4E
Reserved
7E6E
ECON2L
7E8E
EUDARDPTL
7E0F
EDMADSTH
7E2F
EPMM4H
7E4F
Reserved
7E6F
ECON2H
7E8F
EUDARDPTH
7E10
EDMACSL
7E30
EPMCSL
7E50
Reserved
7E70
ERXWML
7E90
EUDAWRPTL
7E11
EDMACSH
7E31
EPMCSH
7E51
Reserved
7E71
ERXWMH
7E91
EUDAWRPTH
7E12
ETXSTATL
7E32
EPMOL
7E52
MICMDL
7E72
EIEL
7E92
Reserved
7E13
ETXSTATH
7E33
EPMOH
7E53
MICMDH
7E73
EIEH
7E93
Reserved
7E14
ETXWIREL
7E34
ERXFCONL
7E54
MIREGADRL
7E74
EIDLEDL
7E94
Reserved
7E15
ETXWIREH
7E35
ERXFCONH
7E55
MIREGADRH
7E75
EIDLEDH
7E95
Reserved
7E16
EUDASTL
7E36
EUDASTL
7E56
EUDASTL
7E76
EUDASTL
7E96
Reserved
7E17
EUDASTH
7E37
EUDASTH
7E57
EUDASTH
7E77
EUDASTH
7E97
Reserved
7E18
EUDANDL
7E38
EUDANDL
7E58
EUDANDL
7E78
EUDANDL
7E98
Reserved
7E19
EUDANDH
7E39
EUDANDH
7E59
EUDANDH
7E79
EUDANDH
7E99
Reserved
7E1A
ESTATL
7E3A
ESTATL
7E5A
ESTATL
7E7A
ESTATL
7E9A
Reserved
7E1B
ESTATH
7E3B
ESTATH
7E5B
ESTATH
7E7B
ESTATH
7E9B
Reserved
7E1C
EIRL
7E3C
EIRL
7E5C
EIRL
7E7C
EIRL
7E9C
Reserved
7E1D
EIRH
7E3D
EIRH
7E5D
EIRH
7E7D
EIRH
7E9D
Reserved
7E1E
ECON1L
7E3E
ECON1L
7E5E
ECON1L
7E7E
ECON1L
7E9E
—
7E1F
ECON1H
7E3F
ECON1H
7E5F
ECON1H
7E7F
ECON1H
7E9F
—
 2010 Microchip Technology Inc.
DS39935C-page 21
ENC424J600/624J600
TABLE 3-3:
ENC424J600/624J600 SFR MAP (BASE REGISTER MAP, 16-BIT PSP INTERFACE)
Addr
Name
Addr
Name
Addr
Name
Addr
Name
Addr
Name
3F00
ETXST
3F10
EHT1
3F20
MACON1
3F30
MAADR3
3F40
EGPDATA
3F01
ETXLEN
3F11
EHT2
3F21
MACON2
3F31
MAADR2
3F41
ERXDATA
3F02
ERXST
3F12
EHT3
3F22
MABBIPG
3F32
MAADR1
3F42
EUDADATA
3F03
ERXTAIL
3F13
EHT4
3F23
MAIPG
3F33
MIWR
3F43
EGPRDPT
3F04
ERXHEAD
3F14
EPMM1
3F24
MACLCON
3F34
MIRD
3F44
EGPWRPT
3F05
EDMAST
3F15
EPMM2
3F25
MAMXFL
3F35
MISTAT
3F45
ERXRDPT
3F06
EDMALEN
3F16
EPMM3
3F26
Reserved
3F36
EPAUS
3F46
ERXWRPT
3F07
EDMADST
3F17
EPMM4
3F27
Reserved
3F37
ECON2
3F47
EUDARDPT
3F08
EDMACS
3F18
EPMCS
3F28
Reserved
3F38
ERXWM
3F48
EUDAWRPT
3F09
ETXSTAT
3F19
EPMO
3F29
MICMD
3F39
EIE
3F49
Reserved
3F0A
ETXWIRE
3F1A
ERXFCON
3F2A
MIREGADR
3F3A
EIDLED
3F4A
Reserved
3F0B
EUDAST
3F1B
EUDAST
3F2B
EUDAST
3F3B
EUDAST
3F4B
Reserved
3F0C
EUDAND
3F1C
EUDAND
3F2C
EUDAND
3F3C
EUDAND
3F4C
Reserved
3F0D
ESTAT
3F1D
ESTAT
3F2D
ESTAT
3F3D
ESTAT
3F4D
Reserved
3F0E
EIR
3F1E
EIR
3F2E
EIR
3F3E
EIR
3F4E
Reserved
3F0F
ECON1
3F1F
ECON1
3F2F
ECON1
3F3F
ECON1
3F4F
—
3.2.4.1
PSP Bit Set and Bit Clear Registers
A major difference between the SPI and PSP memory
maps is the inclusion of companion Bit Set and Bit
Clear registers for many of the E registers. Since the
PSP interface allows direct access to memory
locations, without a command interpreter, there are no
instructions implemented to perform single bit
manipulations. Instead, this interface implements
separate Bit Set and Bit Clear registers, allowing users
to individually work with volatile bits (such as interrupt
flags) without the risk of disturbing the values of other
bits. Setting the bit(s) in one of these registers sets or
clears the corresponding bit(s) in the base register.
In the PSP interface, Bit Set and Bit Clear registers are
located in different areas of the addressable memory
space from their corresponding “base” SFRs. The
address of the registers is always at a fixed offset from
their corresponding base register. For the 8-bit interface,
the offset is 100h (Set) or 180h (Clear). For the 16-bit
interface, the offset is 80H (Set) or C0 (Clear).
Symbolically, the names of the companion registers are
the names of the base registers, plus the suffix form
“-SET” (or “-SETH/SETL”) for Bit Set registers and
“-CLR” (“-CLRH/CLRL”) for Bit Clear registers.
DS39935C-page 22
Most SFRs have their own pair of Bit Set and Bit Clear
registers. However, these SFRs do not:
• MAC registers, including MI registers for PHY
access
• Read-only status registers (ERXHEAD, ETXSTAT,
ETXWIRE and ESTAT)
• All of the SRAM Buffer Pointers and data windows
(SFRs located at 7E80h to 7E9Fh in the 8-bit
interface, or 3F40h to 3F4Fh in the 16-bit
interface)
The Bit Set and Bit Clear registers for the 8-bit PSP
interface are listed in Table 3-4 and Table 3-5,
respectively. The registers for the 16-bit interface are
listed together in Table 3-6.
 2010 Microchip Technology Inc.
ENC424J600/624J600
TABLE 3-4:
ENC424J600/624J600 SFR MAP (SET REGISTER MAP, 8-BIT PSP INTERFACE)
Bit Set Registers (7F00h to 7F7Fh)(1)
Addr
Name
Addr
Name
Addr
Name
Addr
Name
7F00
ETXSTSETL
7F20
EHT1SETL
7F40
Reserved
7F60
Reserved
7F01
ETXSTSETH
7F21
EHT1SETH
7F41
Reserved
7F61
Reserved
7F02
ETXLENSETL
7F22
EHT2SETL
7F42
Reserved
7F62
Reserved
7F03
ETXLENSETH
7F23
EHT2SETH
7F43
Reserved
7F63
Reserved
7F04
ERXSTSETL
7F24
EHT3SETL
7F44
Reserved
7F64
Reserved
7F05
ERXSTSETH
7F25
EHT3SETH
7F45
Reserved
7F65
Reserved
7F06
ERXTAILSETL
7F26
EHT4SETL
7F46
Reserved
7F66
Reserved
7F07
ERXTAILSETH
7F27
EHT4SETH
7F47
Reserved
7F67
Reserved
7F08
—
7F28
EPMM1SETL
7F48
Reserved
7F68
Reserved
Reserved
7F09
—
7F29
EPMM1SETH
7F49
Reserved
7F69
7F0A
EDMASTSETL
7F2A
EPMM2SETL
7F4A
Reserved
7F6A
Reserved
7F0B
EDMASTSETH
7F2B
EPMM2SETH
7F4B
Reserved
7F6B
Reserved
7F0C
EDMALENSETL
7F2C
EPMM3SETL
7F4C
Reserved
7F6C
EPAUSSETL
7F0D
EDMALENSETH
7F2D
EPMM3SETH
7F4D
Reserved
7F6D
EPAUSSETH
7F0E
EDMADSTSETL
7F2E
EPMM4SETL
7F4E
Reserved
7F6E
ECON2SETL
7F0F
EDMADSTSETH
7F2F
EPMM4SETH
7F4F
Reserved
7F6F
ECON2SETH
7F10
EDMACSSETL
7F30
EPMCSSETL
7F50
Reserved
7F70
ERXWMSETL
ERXWMSETH
7F11
EDMACSSETH
7F31
EPMCSSETH
7F51
Reserved
7F71
7F12
—
7F32
EPMOSETL
7F52
Reserved
7F72
EIESETL
7F13
—
7F33
EPMOSETH
7F53
Reserved
7F73
EIESETH
7F14
—
7F34
ERXFCONSETL
7F54
Reserved
7F74
EIDLEDSETL
7F15
—
7F35
ERXFCONSETH
7F55
Reserved
7F75
EIDLEDSETH
7F16
EUDASTSETL
7F36
EUDASTSETL
7F56
EUDASTSETL
7F76
EUDASTSETL
7F17
EUDASTSETH
7F37
EUDASTSETH
7F57
EUDASTSETH
7F77
EUDASTSETH
7F18
EUDANDSETL
7F38
EUDANDSETL
7F58
EUDANDSETL
7F78
EUDANDSETL
7F19
EUDANDSETH
7F39
EUDANDSETH
7F59
EUDANDSETH
7F79
EUDANDSETH
7F1A
—
7F3A
—
7F5A
—
7F7A
—
7F1B
—
7F3B
—
7F5B
—
7F7B
—
7F1C
EIRSETL
7F3C
EIRSETL
7F5C
EIRSETL
7F7C
EIRSETL
7F1D
EIRSETH
7F3D
EIRSETH
7F5D
EIRSETH
7F7D
EIRSETH
7F1E
ECON1SETL
7F3E
ECON1SETL
7F5E
ECON1SETL
7F7E
ECON1SETL
ECON1SETH
7F3F
ECON1SETH
7F5F
ECON1SETH
7F7F
ECON1SETH
7F1F
Note 1:
Bit Set and Bit Clear registers are not implemented for the base SFRs located between 7E80h and 7E9Fh.
 2010 Microchip Technology Inc.
DS39935C-page 23
ENC424J600/624J600
TABLE 3-5:
ENC424J600/624J600 SFR MAP (CLR REGISTER MAP, 8-BIT PSP INTERFACE)
Bit Clear Registers (7F80h to 7FFFh)(1)
Addr
Name
Addr
Name
Addr
Name
Addr
Name
7F80
ETXSTCLRL
7FA0
EHT1CLRL
7FC0
Reserved
7FE0
Reserved
7F81
ETXSTCLRH
7FA1
EHT1CLRH
7FC1
Reserved
7FE1
Reserved
7F82
ETXLENCLRL
7FA2
EHT2CLRL
7FC2
Reserved
7FE2
Reserved
7F83
ETXLENCLRH
7FA3
EHT2CLRH
7FC3
Reserved
7FE3
Reserved
7F84
ERXSTCLRL
7FA4
EHT3CLRL
7FC4
Reserved
7FE4
Reserved
7F85
ERXSTCLRH
7FA5
EHT3CLRH
7FC5
Reserved
7FE5
Reserved
7F86
ERXTAILCLRL
7FA6
EHT4CLRL
7FC6
Reserved
7FE6
Reserved
7F87
ERXTAILCLRH
7FA7
EHT4CLRH
7FC7
Reserved
7FE7
Reserved
7F88
—
7FA8
EPMM1CLRL
7FC8
Reserved
7FE8
Reserved
Reserved
7F89
—
7FA9
EPMM1CLRH
7FC9
Reserved
7FE9
7F8A
EDMASTCLRL
7FAA
EPMM2CLRL
7FCA
Reserved
7FEA
Reserved
7F8B
EDMASTCLRH
7FAB
EPMM2CLRH
7FCB
Reserved
7FEB
Reserved
7F8C
EDMALENCLRL
7FAC
EPMM3CLRL
7FCC
Reserved
7FEC
EPAUSCLRL
7F8D
EDMALENCLRH
7FAD
EPMM3CLRH
7FCD
Reserved
7FED
EPAUSCLRH
7F8E
EDMADSTCLRL
7FAE
EPMM4CLRL
7FCE
Reserved
7FEE
ECON2CLRL
7F8F
EDMADSTCLRH
7FAF
EPMM4CLRH
7FCF
Reserved
7FEF
ECON2CLRH
7F90
EDMACSCLRL
7FB0
EPMCSCLRL
7FD0
Reserved
7FF0
ERXWMCLRL
7F91
EDMACSCLRH
7FB1
EPMCSCLRH
7FD1
Reserved
7FF1
ERXWMCLRH
7F92
—
7FB2
EPMOCLRL
7FD2
Reserved
7FF2
EIECLRL
7F93
—
7FB3
EPMOCLRH
7FD3
Reserved
7FF3
EIECLRH
7F94
—
7FB4
ERXFCONCLRL
7FD4
Reserved
7FF4
EIDLEDCLRL
7F95
—
7FB5
ERXFCONCLRH
7FD5
Reserved
7FF5
EIDLEDCLRH
7F96
EUDASTCLRL
7FB6
EUDASTCLRL
7FD6
EUDASTCLRL
7FF6
EUDASTCLRL
7F97
EUDASTCLRH
7FB7
EUDASTCLRH
7FD7
EUDASTCLRH
7FF7
EUDASTCLRH
7F98
EUDANDCLRL
7FB8
EUDANDCLRL
7FD8
EUDANDCLRL
7FF8
EUDANDCLRL
7F99
EUDANDCLRH
7FB9
EUDANDCLRH
7FD9
EUDANDCLRH
7FF9
EUDANDCLRH
7F9A
—
7FBA
—
7FDA
—
7FFA
—
7F9B
—
7FBB
—
7FDB
—
7FFB
—
7F9C
EIRCLRL
7FBC
EIRCLRL
7FDC
EIRCLRL
7FFC
EIRCLRL
7F9D
EIRCLRH
7FBD
EIRCLRH
7FDD
EIRCLRH
7FFD
EIRCLRH
7F9E
ECON1CLRL
7FBE
ECON1CLRL
7FDE
ECON1CLRL
7FFE
ECON1CLRL
ECON1CLRH
7FBF
ECON1CLRH
7FDF
ECON1CLRH
7FFF
ECON1CLRH
7F9F
Note 1:
Bit Set and Bit Clear registers are not implemented for the base SFRs located between 7E80h and 7E9Fh.
DS39935C-page 24
 2010 Microchip Technology Inc.
ENC424J600/624J600
TABLE 3-6:
ENC424J600/624J600 SFR MAP (SET/CLR REGISTER MAP, 16-BIT PSP INTERFACE)
Bit Set Registers (3F80h to 3FBFh)(1)
Addr
Name
Addr
Name
Addr
Name
Addr
Name
3F80
ETXSTSET
3F90
EHT1SET
3FA0
Reserved
3FB0
Reserved
3F81
ETXLENSET
3F91
EHT2SET
3FA1
Reserved
3FB1
Reserved
3F82
ERXSTSET
3F92
EHT3SET
3FA2
Reserved
3FB2
Reserved
3F83
ERXTAILSET
3F93
EHT4SET
3FA3
Reserved
3FB3
Reserved
3F84
—
3F94
EPMM1SET
3FA4
Reserved
3FB4
Reserved
3F85
EDMASTSET
3F95
EPMM2SET
3FA5
Reserved
3FB5
Reserved
3F86
EDMALENSET
3F96
EPMM3SET
3FA6
Reserved
3FB6
EPAUSSET
3F87
EDMADSTSET
3F97
EPMM4SET
3FA7
Reserved
3FB7
ECON2SET
3F88
EDMACSSET
3F98
EPMCSSET
3FA8
Reserved
3FB8
ERXWMSET
3F89
—
3F99
EPMOSET
3FA9
Reserved
3FB9
EIESET
3F8A
—
3F9A
ERXFCON
3FAA
Reserved
3FBA
EIDLEDSET
3F8B
EUDASTSET
3F9B
EUDASTSET
3FAB
EUDASTSET
3FBB
EUDASTSET
3F8C
EUDANDSET
3F9C
EUDANDSET
3FAC
EUDANDSET
3FBC
EUDANDSET
3F8D
—
3F9D
—
3FAD
—
3FBD
—
3F8E
EIRSET
3F9E
EIRSET
3FAE
EIRSET
3FBE
EIRSET
3F8F
ECON1SET
3F9F
ECON1SET
3FAF
ECON1SET
3FBF
ECON1SET
Bit Clear Registers (3FC0h to
3FFFh)(1)
Addr
Name
Addr
Name
Addr
Name
Addr
Name
3FC0
ETXSTCLR
3FD0
EHT1CLR
3FE0
Reserved
3FF0
Reserved
3FC1
ETXLENCLR
3FD1
EHT2CLR
3FE1
Reserved
3FF1
Reserved
3FC2
ERXSTCLR
3FD2
EHT3CLR
3FE2
Reserved
3FF2
Reserved
3FC3
ERXTAILCLR
3FD3
EHT4CLR
3FE3
Reserved
3FF3
Reserved
3FC4
—
3FD4
EPMM1CLR
3FE4
Reserved
3FF4
Reserved
3FC5
EDMASTCLR
3FD5
EPMM2CLR
3FE5
Reserved
3FF5
Reserved
3FC6
EDMALENCLR
3FD6
EPMM3CLR
3FE6
Reserved
3FF6
EPAUSCLR
3FC7
EDMADSTCLR
3FD7
EPMM4CLR
3FE7
Reserved
3FF7
ECON2CLR
3FC8
EDMACSCLR
3FD8
EPMCSCLR
3FE8
Reserved
3FF8
ERXWMCLR
3FC9
—
3FD9
EPMOCLR
3FE9
Reserved
3FF9
EIECLR
3FCA
—
3FDA
ERXFCONCLR
3FEA
Reserved
3FFA
EIDLEDCLR
3FCB
EUDASTCLR
3FDB
EUDASTCLR
3FEB
EUDASTCLR
3FFB
EUDASTCLR
3FCC
EUDANDCLR
3FDC
EUDANDCLR
3FEC
EUDANDCLR
3FFC
EUDANDCLR
3FCD
—
3FDD
—
3FED
—
3FFD
—
3FCE
EIRCLR
3FDE
EIRCLR
3FEE
EIRCLR
3FFE
EIRCLR
ECON1CLR
3FDF
ECON1CLR
3FEF
ECON1CLR
3FFF
ECON1CLR
3FCF
Note 1:
Bit Set and Bit Clear registers are not implemented for the base SFRs located between 3F40h and 3F4Fh.
 2010 Microchip Technology Inc.
DS39935C-page 25
High Byte (‘H’ Register)
8-Bit
File
Name
ENC424J600/624J600 REGISTER FILE SUMMARY
Bit 7
16-Bit
Bit 15
Low Byte (‘L’ Register)
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Bit 14
Bit 13
Bit 12
Bit 11
Bit 10
Bit 9
Bit 8
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
EUDAST
—
User-Defined Area Start Pointer (EUDAST<14:8>)
User-Defined Area Start Pointer (EUDAST<7:0>)
EUDAND
—
User-Defined Area End Pointer (EUDAND<14:8>)
User-Defined Area End Pointer (EUDAND<7:0>)
ESTAT
INT
FCIDLE
RXBUSY
CLKRDY
r
PHYDPX
r
PHYLNK
00, 00
5F, FF
PKTCNT7 PKTCNT6 PKTCNT5 PKTCNT4 PKTCNT3
EIR
CRYPTEN MODEXIF
HASHIF
AESIF
LINKIF
r
r
r
r
PKTIF
DMAIF
ECON1
MODEXST HASHEN
HASHOP
HASHLST
AESST
AESOP1
AESOP0
PKTDEC
FCOP1
FCOP0
DMAST
Reset
r
TXIF
PKTCNT2 PKTCNT1 PKTCNT0 00, 00
TXABTIF
DMACPY DMACSSD DMANOCS
RXABTIF
TXRTS
PCFULIF 0A, 00
RXEN
00, 00
ETXST
—
TX Start Address (ETXST<14:8>)
TX Start Address (ETXST<7:0>)
00, 00
ETXLEN
—
TX Length (ETXLEN<14:8>)
TX Length (ETXLEN<7:0>)
00, 00
ERXST
—
RX Buffer Start Address (ERXST<14:8>)
RX Buffer Start Address (ERXST<7:0>)
53, 40
ERXTAIL
—
RX Tail Pointer (ERXTAIL<14:8>)
RX Tail Pointer (ERXTAIL<7:0>)
5F, FE
ERXHEAD
—
RX Head Pointer (ERXHEAD<14:8>)
RX Head Pointer (ERXHEAD<7:0>)
53, 40
EDMAST
—
DMA Start Address (EDMAST<14:8>)
DMA Start Address (EDMAST<7:0>)
00, 00
EDMALEN
—
DMA Length (EDMALEN<14:8>)
DMA Length (EDMALEN<7:0>)
00, 00
EDMADST
—
DMA Destination Address (EDMADST<14:8>)
DMA Destination Address (EDMADST<7:0>)
00, 00
DMA Checksum, Low Byte (EDMACS<7:0>)
00, 00
EDMACS
ETXSTAT
DMA Checksum, High Byte (EDMACS<15:8>)
—
—
—
r
r
LATECOL MAXCOL EXDEFER
DEFER
r
r
CRCBAD COLCNT3 COLCNT2 COLCNT1 COLCNT0 00, 00
ETXWIRE
Transmit Byte Count on Wire (including collision bytes), High Byte (ETXWIRE<15:8>)
Transmit Byte Count on Wire (including collision bytes), Low Byte (ETXWIRE<7:0>)
00, 00
EHT1
Hash Table Filter (EHT1<15:8>)
Hash Table Filter (EHT1<7:0>)
00, 00
EHT2
Hash Table Filter (EHT2<31:24>)
Hash Table Filter (EHT2<23:16>)
00, 00
ETH3
Hash Table Filter (EHT3<47:40>)
Hash Table Filter (EHT3<39:32>)
00, 00
ETH4
Hash Table Filter (EHT4<63:56>)
Hash Table Filter (EHT4<55:48>)
00, 00
EPMM1
Pattern Match Filter Mask (EPMM1<15:8>)
Pattern Match Filter Mask (EPMM1<7:0>)
00, 00
EPMM2
Pattern Match Filter Mask (EPMM2<15:8>)
Pattern Match Filter Mask (EPMM2<7:0>)
00, 00
EPMM3
Pattern Match Filter Mask (EPMM3<15:8>)
Pattern Match Filter Mask (EPMM3<7:0>)
00, 00
EPMM4
Pattern Match Filter Mask (EPMM4<15:8>)
Pattern Match Filter Mask (EPMM4<7:0>)
00, 00
EPMCS
Pattern Match Filter Checksum, High Byte (EPMCS<15:8>)
Pattern Match Filter Checksum, Low Byte (EPMCS<7:0>)
ERXFCON
 2010 Microchip Technology Inc.
EPMO
HTEN
MPEN
—
NOTPM
PMEN3
PMEN2
PMEN1
PMEN0
Pattern Match Filter Offset, High Byte (EPMO<15:8>)
CRCEEN
CRCEN
RUNTEEN RUNTEN
00, 00
UCEN
NOTMEEN
MCEN
BCEN
r
RXPAUS
PASSALL
r
HFRMEN
r
Pattern Match Filter Offset, Low Byte (EPMO<7:0>)
r
r
—
—
r
r
r
r
MACON2
—
DEFER
BPEN
NOBKOFF
—
—
r
r
MABBIPG
—
—
—
—
—
—
—
—
—
BBIPG6
BBIPG5
BBIPG4
BBIPG3
BBIPG2
BBIPG1
BBIPG0
00, 12
MAIPG
—
r
r
r
r
r
r
r
—
IPG6
IPG5
IPG4
IPG3
IPG2
IPG1
IPG0
0C, 12
MACLCON
—
—
r
r
r
r
r
r
—
—
—
—
Legend:
MAC Maximum Frame Length, High Byte (MAMXFL<15:8>)
—
—
LOOPBK
00, 00
MACON1
MAMXFL
—
00, 59
PADCFG2 PADCFG1 PADCFG0 TXCRCEN PHDREN
x0, 0D
FULDPX 40, B2
MAXRET3 MAXRET2 MAXRET1 MAXRET0 37, 0F
MAC Maximum Frame Length, Low Byte (MAMXFL<7:0>)
— = unimplemented, read as ‘0’; q = unique MAC address or silicon revision nibble; r = reserved bit, do not modify; x = Reset value unknown. Reset values are shown in hexadecimal for each byte.
05, EE
ENC424J600/624J600
DS39935C-page 26
TABLE 3-7:
 2010 Microchip Technology Inc.
TABLE 3-7:
High Byte (‘H’ Register)
8-Bit
File
Name
ENC424J600/624J600 REGISTER FILE SUMMARY (CONTINUED)
Low Byte (‘L’ Register)
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Bit 15
Bit 14
Bit 13
Bit 12
Bit 11
Bit 10
Bit 9
Bit 8
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
MICMD
—
—
—
—
—
—
—
—
—
—
—
—
—
—
MIISCAN
MIREGADR
—
—
—
r
r
r
r
r
—
—
—
PHREG4
PHREG3
PHREG2
PHREG1
16-Bit
MIIRD
Reset
--, 00
PHREG0 01, 00
MAADR3
MAC Address, Byte 6 (MAADR<7:0>)
MAC Address, Byte 5 (MAADR<15:8>)
qq, qq
MAADR2
MAC Address, Byte 4 (MAADR<23:16>)
MAC Address, Byte 3 (MAADR<31:24>)/OUI Byte 3
qq, a3
MAADR1
MAC Address, Byte 2 (MAADR<39:32>)/OUI Byte 2
MAC Address, Byte 1 (MAADR<47:40>)/OUI Byte 1
04, 00
MIWR
MII Management Write Data, High Byte (MIWR<15:8>)
MII Management Write Data, Low Byte (MIWR<7:0>)
00, 00
MIRD
MII Management Read Data, High Byte (MIRD<15:8>)
MII Management Read Data, Low Byte (MIRD<7:0>)
MISTAT
EPAUS
—
—
—
—
—
—
—
—
Pause Timer Value, High Byte (EPAUS<15:8>)
ECON2
ETHEN
ERXWM
RXFWM7
STRCH
TXMAC
—
—
—
00, 00
r
NVALID
SCAN
BUSY
Pause Timer Value, Low Byte (EPAUS<7:0>)
SHA1MD5
COCON3
COCON2 COCON1 COCON0
AUTOFC
TXRST
RXRST
ETHRST
RXFWM2 RXFWM1 RXFWM0 RXEWM7 RXEWM6 RXEWM5 RXEWM4
--, 00
10, 00
MODLEN1 MODLEN0 AESLEN1 AESLEN0 CB, 00
RXFWM4
RXFWM3
RXEWM3
RXEWM2
RXEWM1 RXEWM0 10, 0F
INTIE
MODEXIE
HASHIE
AESIE
LINKIE
r
r
r
r
PKTIE
DMAIE
r
TXIE
TXABTIE
RXABTIE
LACFG3
LACFG2
LACFG1
LACFG0
LBCFG3
LBCFG2
LBCFG1
LBCFG0
DEVID2
DEVID1
DEVID0
REVID4
REVID3
REVID2
REVID1
EGPDATA
r
r
r
r
r
r
r
r
General Purpose Data Window Register
--, xx
ERXDATA
r
r
r
r
r
r
r
r
Ethernet RX Data Window Register
--, xx
EUDADATA
r
r
r
r
r
r
r
r
User-Defined Area Data Window Register
--, xx
EGPRDPT
—
General Purpose Window Read Pointer, High Byte (ETXRDPT<14:8>)
General Purpose Window Read Pointer, Low Byte (ETXRDPT<7:0>)
05, FA
EGPWRPT
—
General Purpose Window Write Pointer, High Byte (ETXWRPT<14:8>)
General Purpose Window Write Pointer, Low Byte (ETXWRPT<7:0>)
00, 00
ERXRDPT
—
RX Window Read Pointer, High Byte (ERXRDPT<14:8>)
RX Window Read Pointer, Low Byte (ERXRDPT<7:0>)
05, FA
ERXWRPT
—
RX Window Write Pointer, High Byte (ERXWRPT<14:8>)
RX Window Write Pointer, Low Byte (ERXWRPT<7:0>)
00, 00
EUDARDPT
—
UDA Window Read Pointer (EUDARDPT<14:8>)
UDA Window Read Pointer (EUDARDPT<7:0>)
05, FA
EUDAWRPT
—
UDA Window Write Pointer (EUDAWRPT<14:8>)
UDA Window Write Pointer (EUDAWRPT<7:0>)
00, 00
EIE
EIDLED
PCFULIE 80, 10
REVID0
— = unimplemented, read as ‘0’; q = unique MAC address or silicon revision nibble; r = reserved bit, do not modify; x = Reset value unknown. Reset values are shown in hexadecimal for each byte.
26, qq
DS39935C-page 27
ENC424J600/624J600
Legend:
RXFWM6 RXFWM5
—
ENC424J600/624J600
3.3
PHY Special Function Registers
The PHY registers provide configuration and control of
the PHY module, as well as status information about its
operation. These 16-bit registers are located in their
own memory space, outside of the main SFR space.
Unlike other SFRs, the PHY SFRs are not directly
accessible through the SPI or PSP interfaces. Instead,
access is accomplished through a special set of MAC
control registers that implement a Media Independent
Interface Management (MIIM) defined by IEEE 802.3;
these are the MICMD, MISTAT and MIREGADR
registers.
There are a total of 32 PHY addresses; however, only
10 locations implement user-accessible registers listed
in Table 3-8. Writes to unimplemented locations are
ignored and any attempts to read these locations return
FFFFh. Do not write to reserved PHY register locations
and ignore their content if read.
TABLE 3-8:
PHY SPECIAL FUNCTION
REGISTER MAP
3.3.1
READING PHY REGISTERS
When a PHY register is read, the entire 16 bits are
obtained.
To read from a PHY register:
1.
2.
3.
4.
5.
Write the address of the PHY register to read
from
into
the
MIREGADR
register
(Register 3-1). Make sure to also set reserved
bit 8 of this register.
Set the MIIRD bit (MICMD<0>, Register 3-2).
The read operation begins and the BUSY bit
(MISTAT<0>, Register 3-3) is automatically set
by hardware.
Wait 25.6 s. Poll the BUSY (MISTAT<0>) bit to
be certain that the operation is complete. While
busy, the host controller should not start any
MIISCAN operations or write to the MIWR
register. When the MAC has obtained the register
contents, the BUSY bit will clear itself.
Clear the MIIRD (MICMD<0>) bit.
Read the desired data from the MIRD register.
For 8-bit interfaces, the order that these bytes
are read is unimportant.
Address
Name
Address
Name
00
PHCON1
10
Reserved
3.3.2
01
PHSTAT1
11
PHCON2
02
Reserved
12
Reserved
03
Reserved
13
—
04
PHANA
14
Reserved
05
PHANLPA
15
Reserved
When a PHY register is written to, the entire 16 bits are
written at once; selective bit writes are not
implemented. If it is necessary to reprogram only select
bits in the register, the host microcontroller must first
read the PHY register, modify the resulting data and
then write the data back to the PHY register.
06
PHANE
16
Reserved
To write to a PHY register:
07
—
17
Reserved
1.
08
—
18
—
09
—
19
—
0A
—
1A
—
0B
—
1B
PHSTAT2
0C
—
1C
Reserved
0D
—
1D
Reserved
0E
—
1E
Reserved
0F
—
1F
PHSTAT3
DS39935C-page 28
2.
3.
WRITING PHY REGISTERS
Write the address of the PHY register to write to
into the MIREGADR register. Make sure to also
set reserved bit 8 of this register.
Write the 16 bits of data into the MIWR register.
The low byte must be written first, followed by
the high byte.
Writing to the high byte of MIWR begins the
MIIM transaction and the BUSY (MISTAT<0>)
bit is automatically set by hardware.
The PHY register is written after the MIIM operation
completes, which takes 25.6 s. When the write operation has completed, the BUSY bit clears itself. The host
controller should not start any MIISCAN, MIWR or
MIIRD operations while the BUSY bit is set.
 2010 Microchip Technology Inc.
ENC424J600/624J600
3.3.3
SCANNING A PHY REGISTER
The MAC can be configured to perform automatic
back-to-back read operations on a PHY register. This
can reduce the host controller complexity when
periodic status information updates are desired.
To perform the scan operation:
1.
2.
Write the address of the PHY register to read
from into the MIREGADR register. Make sure to
also set reserved bit 8 of this register.
Set the MIISCAN (MICMD<1>) bit. The scan
operation begins and the BUSY (MISTAT<0>)
bit is automatically set by hardware. The first
read operation will complete after 25.6 s. Subsequent reads will be done at the same interval
until the operation is cancelled. The NVALID
(MISTAT<2>) bit may be polled to determine
when the first read operation is complete.
REGISTER 3-1:
After setting the MIISCAN bit, the MIRD register will
automatically be updated every 25.6 s. There is no
status information which can be used to determine
when the MIRD registers are updated. On the SPI or
8-bit PSP interfaces, the host controller can only read
one register location at a time. Therefore, it must not be
assumed that the values of MIRDL and MIRDH were
read from the PHY at exactly the same time.
When the MIISCAN operation is in progress, the host
controller must not attempt to write to MIWR or start an
MIIRD operation. The MIISCAN operation can be
cancelled by clearing the MIISCAN (MICMD<1>) bit
and then polling the BUSY (MISTAT<0>) bit. New
operations may be started after the BUSY bit is cleared.
MIREGADR: MII MANAGEMENT ADDRESS REGISTER
U-0
U-0
U-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-1
—
—
—
r
r
r
r
r
bit 15
bit 8
U-0
U-0
U-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
—
—
—
PHREG4
PHREG3
PHREG2
PHREG1
PHREG0
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 15-13
Unimplemented: Read as ‘0’
bit 12-8
Reserved: Write as ‘00001’ (01h)
bit 7-5
Unimplemented: Read as ‘0’
bit 4-0
PHREG<4:0>: MII Management PHY Register Address Select bits
The address of the PHY register which MII Management read and write operations will apply to.
 2010 Microchip Technology Inc.
DS39935C-page 29
ENC424J600/624J600
REGISTER 3-2:
MICMD: MII MANAGEMENT COMMAND REGISTER
U-0
U-0
U-0
U-0
U-0
U-0
U-0
U-0
—
—
—
—
—
—
—
—
bit 15
bit 8
U-0
U-0
U-0
U-0
U-0
U-0
R/W-0
R/W-0
—
—
—
—
—
—
MIISCAN
MIIRD
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 15-2
Unimplemented: Read as ‘0’
bit 1
MIISCAN: MII Scan Enable bit
1 = PHY register designated by MIREGADR<4:0> is continuously read and the data is copied to MIRD
0 = No MII Management scan operation is in progress
bit 0
MIIRD: MII Read Enable bit
1 = PHY register designated by MIREGADR<4:0> is read once and the data is copied to MIRD
0 = No MII Management read operation is in progress
REGISTER 3-3:
MISTAT: MII MANAGEMENT STATUS REGISTER
U-0
U-0
U-0
U-0
U-0
U-0
U-0
U-0
—
—
—
—
—
—
—
—
bit 15
bit 8
U-0
U-0
U-0
U-0
R-0
R-0
R-0
R-0
—
—
—
—
r
NVALID
SCAN
BUSY
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 15-4
Unimplemented: Read as ‘0’
bit 3
Reserved: Ignore on read
bit 2
NVALID: MII Management Read Data Not Valid Status bit
1 = The contents of MIRD are not valid yet
0 = The MII Management read cycle has completed and MIRD has been updated
bit 1
SCAN: MII Management Scan Status bit
1 = MII Management scan operation is in progress
0 = No MII Management scan operation is in progress
bit 0
BUSY: MII Management Busy Status bit
1 = A PHY register is currently being read or written to
0 = The MII Management interface is Idle
DS39935C-page 30
 2010 Microchip Technology Inc.
 2010 Microchip Technology Inc.
TABLE 3-9:
PHY REGISTER FILE SUMMARY
File Name
Bit 15
Bit 14
PHCON1
PRST
PLOOPBK
PHSTAT1
r
FULL100
Bit 13
Bit 12
Bit 11
Bit 10
Bit 9
Bit 8
Bit 7
Bit 6
Bit 5
Bit 4
SPD100
ANEN
PSLEEP
r
RENEG
PFULDPX
r
r
r
r
HALF100
FULL10
HALF10
r
r
r
r
r
ANDONE
LRFAULT
Bit 3
Bit 0
Value
on
Reset
r
10, 00
Bit 2
Bit 1
r
r
r
ANABLE
LLSTAT
r
EXTREGS 78, 09
ADIEEE0 01, E1
PHANA
ADNP
r
ADFAULT
r
ADPAUS1 ADPAUS0
r
AD100FD
AD100
AD10FD
AD10
ADIEEE4
ADIEEE3
ADIEEE2
ADIEEE1
PHANLPA
LPNP
LPACK
LPFAULT
r
LPPAUS1
LPPAUS0
LP100T4
LP100FD
LP100
LP10FD
LP10
LPIEEE4
LPIEEE3
LPIEEE2
LPIEEE1
LPIEEE0
PHANE
r
r
r
r
r
r
r
r
r
r
r
PDFLT
r
r
LPARCD
LPANABL 00, 00
xx, xx
PHCON2
r
r
EDPWRDN
r
EDTHRES
r
r
r
r
r
r
r
r
FRCLNK
EDSTAT
r
00, 02
PHSTAT2
r
r
r
r
r
r
r
r
r
r
r
PLRITY
r
r
r
r
xx, 0x
PHSTAT3
r
r
r
r
r
r
r
r
r
r
r
r
r
00, 40
Legend:
SPDDPX2 SPDDPX1 SPDDPX0
r = reserved bit, write as ‘0’; ignore on read; x = unknown. Reset values are shown in hexadecimal for each byte.
ENC424J600/624J600
DS39935C-page 31
ENC424J600/624J600
3.4
Cryptographic Data Memory
The cryptographic data memory is used to store key
and data information for the Modular Exponentiation,
AES and MD5/SHA-1 hashing engines. The RAM for
these modules is actually implemented inside of the
modules themselves; this allows fast memory access
for the access-intensive encryption engines, as well as
the simultaneous use of more than one module by an
application. This memory is mapped into an area of
address space that is accessible only by the DMA
controller. The host controller must write to the cryptographic data memory by writing data to the 24-Kbyte
SRAM buffer, then using the DMA to copy it into the
security engine. Reading is performed in the opposite
order, using the DMA to copy the data out of the
security engine and into the SRAM buffer.
The mapping of the cryptographic space is shown in
Figure 3-3. For additional information on the cryptographic engines, refer to Section 15.0 “Cryptographic
Security Engines”. For additional information on the
DMA controller, see Section 14.0 “Direct Memory
Access (DMA) Controller”.
FIGURE 3-3:
3.5
SRAM Buffer
The SRAM buffer is a bulk 12K word x 16-bit (24 Kbytes)
memory, used for TX/RX packet buffering and general
purpose storage by the host microcontroller. In most
cases, the memory is accessed using a byte-oriented
interface, so the memory can normally be thought of as
a simple 24-Kbyte memory buffer divided into a general
purpose/TX area and an RX area (Figure 3-4).
FIGURE 3-4:
SRAM BUFFER
ORGANIZATION
0000h
General Purpose
Buffer
CRYPTOGRAPHIC DATA
MEMORY MAPPING
ERXST – 1
ERXST
Modular Exponentiation
DMA Pointers
Exponent (E)
(up to 1024 bits)
Data/Result (X/Y)
(up to 1024 bits)
Modulus (M)
(512, 768 or 1024 bits)
7800h
787Fh
7880h
78FFh
7900h
797Fh
MD5/SHA-1 Hash
Unimplemented
Data In
(512 bits)
Initialization Vector/State In
(160 bits)
Length State In (55 bits)
Digest/State Out
(128 or 160 bits)
Length State Out (55 bits)
7A00h
7A3Fh
7A40h
7A53h
7A54h
7A5Bh
7A70h
7A83h
7A84h
7A8Bh
Unimplemented
AES
Encryption Key
(128, 192 or 256 bits)
Text A In/Out (128 bits)
Text B In/Out (128 bits)
XOR Out (128 bits)
DS39935C-page 32
Circular RX FIFO
Buffer
5FFFh
Ethernet communications on 10Base-T and
100Base-TX networks occur at a fixed speed of
10 Mbps or 100 Mbps, respectively. Intra-byte gaps are
not allowed. This requires the host controller to build
outbound transmit frames in their entirety in the SRAM
buffer before the hardware is allowed to begin transmission. Similarly, when receiving packets, the buffer
provides space for the hardware to write the incoming
packet without forcing the host microcontroller to
immediately read and process the packet.
After the part exits Reset, the entire buffer is accessible
by the host controller, regardless of other transmit,
receive or DMA operations that may simultaneously
also be accessing the general purpose or receive
buffer memory.
7C00h
7C1Fh
7C20h
7C2Fh
7C30h
7C3Fh
7C40h
7C4Fh
 2010 Microchip Technology Inc.
ENC424J600/624J600
3.5.1
GENERAL PURPOSE BUFFER
The general purpose buffer memory starts at address
0000h and includes all memory up to, but not including,
the memory address pointed to by the ERXST register
(i.e., ERXST – 1).
This buffer can be used to store transmit packets,
received data that the host controller wishes to save for
an extended period, or any type of volatile or state
information that the host controller does not have room
internally to save. Upper layer communications protocols and applications, such as a TCP/IP stack with SSL
or TLS security, are generally infeasible or will perform
poorly over high latency Internet links without using
large buffers.
For reliable, connection oriented protocols like TCP, the
maximum theoretical throughput is directly proportional
to the round trip Acknowledgement latency of the link
and the size of the corresponding transmit or receive
buffer. The general purpose buffer memory on the
ENCX24J600 is well suited for use by TCP for
implementing
high-performance
communications
across the Internet, where round trip Acknowledgement
latency is in the order of many milliseconds.
3.5.2
RECEIVE BUFFER
The receive buffer constitutes a circular FIFO buffer
managed by hardware. The buffer extends inclusively
from the byte pointed to by the ERXST Pointer, to the
very end of the SRAM at address 5FFFh. The size of
the buffer, in bytes, is therefore defined as:
RX Buffer Size = 5FFFh – ERXST + 1
As bytes of data are received from the Ethernet
interface, they are written into the receive buffer
sequentially. However, after the memory at address
5FFFh is written to, the hardware will automatically
wrap around and write the next byte of received data to
the ERXST address. As a result, the receive hardware
will never write outside the boundaries of the RX FIFO
buffer.
For proper 16-bit word alignment, the ERXST Pointer is
required to point to an even memory address. The
Least Significant bit of this register is read-only and
fixed as ‘0’ to force even alignment. All other
implemented bits in this register are read/write and can
be programmed by software to point to any even
address, from 0000h to 5FFEh.
The default value of ERXST on device Reset is 5340h.
This allocates 21,312 bytes to the general purpose
buffer and 3,264 bytes to the RX buffer. This RX buffer
size is adequate to store at least two maximum length
Ethernet frames, or any combination of numerous
smaller packets.
 2010 Microchip Technology Inc.
The host controller may only program the ERXST
Pointer when the receive logic is disabled. The pointer
must not be modified while the receive logic is enabled
by having RXEN (ECON1<0>) set.
The receive memory is always accessible to the RX
hardware, regardless of transmit, DMA operations or
host controller read/write operations, which may be
accessing the SRAM simultaneously. The RX
hardware will never drop a packet due to insufficient
memory access bandwidth.
3.5.3
TRANSMIT BUFFER
The ENC624J600 family does not implement a dedicated transmit buffer. The transmit hardware has the
flexibility of transmitting data starting at any memory
address, including odd memory addresses which are
off of a 16-bit word boundary. The host controller can
transmit data from either the general purpose area or
RX FIFO area of the entire 24 Kbytes of SRAM.
Because of the transmit flexibility, the host controller may
store many prebuilt packets in the general purpose
buffer for quick transmission. Alternatively, because the
hardware can transmit data from the receive buffer, it is
possible to quickly modify certain packet header fields
and retransmit received packets without reading the
entire packet contents into the host microcontroller. This
feature may improve performance on certain proxy,
gateway or echoing (“ping”) applications.
The transmit hardware performs reads from the SRAM
only; it never writes anything into the SRAM.
The entire SRAM is always accessible to the TX
hardware, regardless of the receive activity, DMA
operations or host controller read/write operations,
which may be simultaneously attempting to access the
SRAM.
3.5.4
DIRECT SRAM BUFFER ACCESS
When one of the PSP interfaces is used, the SRAM
buffer is directly accessible through the interface.
Assuming that all necessary address lines are connected, all addresses in the memory maps shown in
Figure 3-2 (except for the cryptographic data memory)
may be directly read and written to. When accessed
through this manner, the host controller must handle all
address increment and wrap-around calculations that
may be necessary. This also includes translation from
byte to word addressing when a 16-bit PSP interface is
used.
Direct access is unavailable when the SPI interface is
used.
DS39935C-page 33
ENC424J600/624J600
3.5.5
INDIRECT SRAM BUFFER ACCESS
Indirect access to the SRAM buffer is available to all I/O
interfaces. For the SPI interface, it is the only method
available. For PSP interfaces, it may be used in
addition to the direct access method.
Three separate pointer pairs are available for the host
microcontroller to use when accessing the SRAM:
• General Purpose Buffer Read/Write Pointer
(EGPRDPT/EGPWRPT)
• Receive Buffer Read/Write Pointer
(ERXRDPT/ERXWRPT)
• User-Defined Area Read/Write Pointer
(EUDARDPT/EUDAWRPT)
Each of these pointer pairs provides an 8-bit virtual
window register (EGPDATA, ERXDATA and EUDATA)
through which the SRAM data is read or written. The
pointers and their associated data windows are shown
in Figure 3-5.
FIGURE 3-5:
EGPDATA, ERXDATA and EUDADATA are all 8 bits
wide. When writing to them using a 16-bit PSP
interface, the low-order byte select or write enable must
be used; strobing the high byte Byte Select or Write
Enable has no effect. When reading from a 16-bit PSP
interface, one byte of useful data will be returned on the
lower 8 bits of the data bus; the upper 8 bits are to be
ignored.
When a data window register is read, the memory
contents at the address indicated by the corresponding
Read Pointer are obtained and presented to the host
microcontroller. Similarly, when a data window register
is written, the memory contents at the address
indicated by the corresponding Write Pointer are
updated by the data from the host microcontroller.
Following a read/write operation, the appropriate
pointer is automatically incremented in hardware.
POINTERS FOR INDIRECT BUFFER ACCESS
Buffer Pointers
0000h
Data Windows
Write
EGPDATA
Write
ERXDATA
EGPDATA
EGPWRPT
ERXDATA
ERXWRPT
General Purpose
Buffer
Read
EUDADATA
EUDARDPT
EUDADATA
EUDAWRPT
EUDADATA
Write
ERXST – 1
ERXST
Read
EGPDATA
EGPRDPT
Circular RX FIFO
Buffer
Read
ERXDATA
Unimplemented
DS39935C-page 34
ERXRDPT
5FFFh
EUDAST
EUDAND
 2010 Microchip Technology Inc.
ENC424J600/624J600
For example, to read data from address 5402h of the
buffer:
1.
2.
Write 5402h to EGPRDPT.
Read from EGPDATA.
Following the read, the EGPRDPT value normally
increments by 1 (to 5403h in this example). If the host
subsequently wants to read from address 5403h, it can
simply perform a second read from the EGPDATA
Window register. The Write Pointer, EGPWRPT, is not
affected by the read operation.
Similarly, to write A3h to address 0007h of the buffer:
1.
2.
Write 0007h to EGPWRPT.
Write A3h to EGPDATA.
3.5.5.1
Circular Wrapping with EGPDATA
Normally, operations involving EGPDATA cause the
EGPRDPT or EGPWRPT Pointer to automatically
increment by one byte address. However, if the end of
the general purpose buffer area (ERXST – 1) is
reached, or the end of the implemented SRAM (5FFFh)
is reached, the pointer will increment to address 0000h
instead, causing subsequent accesses to wrap around
to the beginning of the SRAM buffer (Figure 3-6). The
increment behavior logic is explained in Equation 3-1.
FIGURE 3-6:
CIRCULAR BUFFER
WRAPPING USING THE
EGPDATA WINDOW
Following the write, the EGPWRPT value normally
increments by 1 (to 0008h in this example). The Read
Pointer, EGPRDPT, is not affected by the write
operation.
Each of the three pointer sets (general purpose,
receive and user-defined area) can be used to access
any address within the SRAM buffer. They differ from
each other based on their address wrapping behavior.
Applications may choose to use all three pointer
interfaces to access the RAM. This may offer maximum
application performance as it will require minimal context switching overhead when, for example, switching
from reading a received packet to reading from general
purpose RAM. However, for simplicity, some
applications may prefer to use only one or two of the
three E*DATA interfaces.
EQUATION 3-1:
0000h
General Purpose
Buffer
ERXST – 1
ERXST
Circular RX FIFO
Buffer
5FFFh
Unimplemented
POINTER INCREMENT LOGIC FOR EGPRDPT AND EGPWRPT
if EGPRDPT/EGPWRPT = ERXST – 1, then
EGPRDPT/EGPWRPT = 0000h
else if EGPRDPT/EGPWRPT = 5FFFh, then
EGPRDPT/EGPWRPT = 0000h
else
EGPRDPT/EGPWRPT = EGPRDPT/EGPWRPT + 1
 2010 Microchip Technology Inc.
DS39935C-page 35
ENC424J600/624J600
3.5.5.2
Circular Wrapping with ERXDATA
FIGURE 3-7:
As with the general purpose pointers, operations with
ERXDATA normally cause the ERXRDPT or
ERXWRPT Pointer to automatically increment by one
byte address. However, if the end of the receive buffer
area (5FFFh) is reached, the pointer will increment to
the start of the receive FIFO buffer area instead, as
defined by ERXST (Figure 3-7).
CIRCULAR BUFFER
WRAPPING USING THE
ERXDATA WINDOW
0000h
General Purpose
Buffer
The receive wrapping rules for the ERXDATA interface
are identical to the buffer wrapping rules used by the
receive hardware. Therefore, this register interface is
ideally suited to reading packet data from the receive
buffer. The host controller can set the ERXRDPT value
at the start of a packet in the receive buffer and sequentially read out the entire packet contents without having
to write to the ERXRDPT Read Pointer again.
ERXST – 1
ERXST
Circular RX FIFO
Buffer
5FFFh
Unimplemented
EQUATION 3-2:
POINTER INCREMENT LOGIC FOR ERXRDPT AND ERXWRPT
if ERXRDPT/ERXWRPT = 5FFFh, then
ERXRDPT/ERXWRPT = ERXST
else
ERXRDPT/ERXWRPT = ERXRDPT/ERXWRPT + 1
3.5.5.3
Circular Wrapping with EUDADATA
The user-defined buffer area is primarily useful for
setting up a circular FIFO within the general purpose
area for use by TCP/IP stacks or other applications. The
wrap-around behavior of the user-defined buffer area is
somewhat more complicated than with the general
purpose or receive buffer cases. This is because the
user-definable boundaries set by EUDAST and
EUDAND take priority over normal wrapping behavior.
Like other pointers, EUDAST and EUDAND are fully
user-configurable from the host microcontroller. Unlike
ERXST, which must not be modified while the receive
hardware is enabled, EUDAST and EUDAND can be
modified at any time.
EQUATION 3-3:
As in the previous instances, operations with
EUDADATA normally cause the EUDARDPT or
EUDAWRPT Pointer to automatically increment by one
byte address. If the value in EUDAND is reached, the
pointer will increment to the address specified by
EUDAST instead. However, if the end of memory
(5FFFh) is reached, and EUDAND is located at some
other address, the pointer will increment to the beginning of memory (0000h). If EUDAND is set to 5FFFh,
the pointer address increments to the value of
EUDAST, instead of 0000h.
The increment
Equation 3-3.
behavior
logic
is
explained
in
POINTER INCREMENT LOGIC FOR EUDARDPT AND EUDAWRPT
if EUDARDPT/EUDAWRPT = EUDAND, then
EUDARDPT/EUDAWRPT = EUDAST
else if EUDARDPT/EUDAWRPT = 5FFFh, then
EUDARDPT/EUDAWRPT = 0000h
else
EUDARDPT/EUDAWRPT = EUDARDPT/EUDAWRPT + 1
DS39935C-page 36
 2010 Microchip Technology Inc.
ENC424J600/624J600
The user-defined area start address, EUDAST, is a
read/write register. For wrapping to work correctly, the
hardware enforces 16-bit even word alignment of this
register by internally having the Least Significant bit
tied off to ‘0’. Similarly, the user-defined area end
address, EUDAND, is a read/write register that is
forced to an odd memory address. The Least Significant bit of EUDAND is internally tied to ‘1’. Applications
wishing to set up general purpose circular FIFOs in
memory using these hardware features must observe
these same alignment requirements.
user-defined area pointers will jump over the range of
addresses between EUDAND and EUDAST. This is
shown in Case 2.
If the user-defined area end address, EUDAND, is at a
higher memory address relative to the start address,
EUDAST, the buffer wraps to either EUDAST or the
beginning of memory, depending on where the
EUDARDPT or EUDAWRPT Pointers are located. This
is shown in Case 1 of Figure 3-8.
When the user-defined buffer is disabled, the host controller can use the EUDADATA interface as a second
general purpose window into RAM. Unlike the original
general purpose pointers, however, EUDARDPT and
EUDAWRPT do not wrap at the ERXST boundary,
thereby allowing access to the full SRAM buffer area.
This may be beneficial for debugging and testing
purposes where it may be desirable to read or write the
entire SRAM buffer in a single operation.
In some cases (for example, when accessing
fragmented data), it may be useful to place the
EUDAST Pointer at a higher memory address relative
to the end address. When organized in such a manner,
an “exclusion zone” in the middle of the memory range
is created; sequential read/write operations with the
FIGURE 3-8:
If the user-defined buffer is not needed, it can
effectively be disabled by setting EUDAST and
EUDAND to addresses outside of the implemented
memory area. For example, if EUDAST is set to 6000h
and EUDAND is set to 6001h, EUDARDPT and
EUDAWRPT will never reach these addresses.
Instead, they wrap from the end of implemented RAM
to its beginning, as shown in Case 3.
CIRCULAR BUFFER WRAPPING USING THE EUDATA WINDOW
0000h
User-Defined
Buffer
0000h
0000h
EUDAST
EUDAND
General Purpose
Buffer
EUDAND
General Purpose
Buffer
Excluded
Circular RX FIFO
Buffer
Circular RX FIFO
Buffer
General Purpose
Buffer
EUDAST
5FFFh
Circular RX FIFO
Buffer
5FFFh
5FFFh
EUDAST
EUDAND
Unimplemented
Unimplemented
Case 1:
EUDAND > EUDAST
Normal User-Defined Buffer
Case 2:
EUDAST > EUDAND
Case 3:
EUDAST and EUDAND > 5FFFh
User-Defined Buffer with
“Exclusion Zone”
User-Defined Buffer Disabled
 2010 Microchip Technology Inc.
Unimplemented
DS39935C-page 37
ENC424J600/624J600
NOTES:
DS39935C-page 38
 2010 Microchip Technology Inc.
ENC424J600/624J600
4.0
SERIAL PERIPHERAL
INTERFACE (SPI)
ENC424J600/624J600 devices implement an optional
SPI I/O port for applications where a parallel microcontroller interface is not available or is undesirable. An
SPI port is commonly available on many microcontrollers, and can be simulated in software on regular
I/O pins where it is not implemented. This makes the
SPI port ideal for using ENC424J600/624J600 devices
with the widest possible range of host controllers.
4.2
SPI Instruction Set
The SPI interface supports a unique instruction set,
consisting of 47 distinct opcodes. These include a large
number of optimized opcodes that perform a wide
range of frequently performed operations with a minimum of SPI protocol overhead. Complete Ethernet
functionality can be achieved with as few as six N-byte
opcodes. The use of the other 41 is optional; however,
doing so will generally improve overall system
performance.
The SPI opcodes are divided into four families:
4.1
Physical Implementation
The SPI port on ENC424J600/624J600 devices
operates as a slave port only. The host controller must
be configured as an SPI master that generates the
Serial Clock (SCK) signal.
This implementation supports SPI Mode 0,0, which
requires:
• SCK is Idle at a logic low state
• Data is clocked in on rising clock edges and
changes on falling clock edges
Other SPI modes that use inverted clock polarity and/or
phase are not supported.
Commands and data are sent to the device on the SI
pin. Data is driven out on the SO line on the falling edge
of SCK. The CS pin must be held low while any
operation is performed, and returned to logic high when
finished.
• Single Byte: Direct opcode instructions; designed
for task-oriented SFR operations with no data
returned
• Two-Byte: Direct opcode instruction; designed for
SFR operation with byte data returned
• Three-Byte: Opcode with word length argument;
includes read and write operations, designed for
pointer manipulation with word length data
returned
• N-Byte: Opcode with one or more bytes of
argument; includes read and write operations
designed for general memory space access with
one or more bytes of data returned
A complete summary of all opcodes is provided in
Table 4-1. A detailed explanation of each opcode family
follows.
When CS is in the inactive (logic high) state, the SO pin
is set to a high-impedance state and becomes 5V tolerant. This allows the ENCX24J600 to be connected to a
single SPI bus shared by multiple SPI slave devices
that also go to a high-impedance state when inactive.
For details on the physical connections to the interface,
see Section 2.7 “Host Interface Pins”.
 2010 Microchip Technology Inc.
DS39935C-page 39
ENC424J600/624J600
TABLE 4-1:
SPI INSTRUCTION SET
Instruction
Mnemonic
Instruction
1st Byte
2nd Byte
3rd Byte
Nth Byte
Bank 0 Select
B0SEL
1100 0000
—
—
—
Bank 1 Select
B1SEL
1100 0010
—
—
—
Bank 2 Select
B2SEL
1100 0100
—
—
—
Bank 3 Select
B3SEL
1100 0110
—
—
—
System Reset
SETETHRST
1100 1010
—
—
—
Flow Control Disable
FCDISABLE
1110 0000
—
—
—
Flow Control Single
FCSINGLE
1110 0010
—
—
—
Flow Control Multiple
FCMULTIPLE
1110 0100
—
—
—
Flow Control Clear
FCCLEAR
1110 0110
—
—
—
Decrement Packet Counter
SETPKTDEC
1100 1100
—
—
—
DMA Stop
DMASTOP
1101 0010
—
—
—
DMA Start Checksum
DMACKSUM
1101 1000
—
—
—
DMA Start Checksum with Seed
DMACKSUMS
1101 1010
—
—
—
DMA Start Copy
DMACOPY
1101 1100
—
—
—
DMA Start Copy and Checksum with Seed
DMACOPYS
1101 1110
—
—
—
Request Packet Transmission
SETTXRTS
1101 0100
—
—
—
Enable RX
ENABLERX
1110 1000
—
—
—
Disable RX
DISABLERX
1110 1010
—
—
—
Enable Interrupts
SETEIE
1110 1100
—
—
—
Disable Interrupts
CLREIE
1110 1110
—
—
—
Read Bank Select
RBSEL
1100 1000
xxxx xxxx
—
—
Write EGPRDPT
WGPRDPT
0110 0000
dddd dddd
DDDD DDDD
—
Read EGPRDPT
RGPRDPT
0110 0010
xxxx xxxx
XXXX XXXX
—
Write ERXRDPT
WRXRDPT
0110 0100
dddd dddd
DDDD DDDD
—
Read ERXRDPT
RRXRDPT
0110 0110
xxxx xxxx
XXXX XXXX
—
Write EUDARDPT
WUDARDPT
0110 1000
dddd dddd
DDDD DDDD
—
Read EUDARDPT
RUDARDPT
0110 1010
xxxx xxxx
XXXX XXXX
—
Write EGPWRPT
WGPWRPT
0110 1100
dddd dddd
DDDD DDDD
—
Read EGPWRPT
RGPWRPT
0110 1110
xxxx xxxx
XXXX XXXX
—
Write ERXWRPT
WRXWRPT
0111 0000
dddd dddd
DDDD DDDD
—
Read ERXWRPT
RRXWRPT
0111 0010
xxxx xxxx
XXXX XXXX
—
Write EUDAWRPT
WUDAWRPT
0111 0100
dddd dddd
DDDD DDDD
—
Read EUDAWRPT
RUDAWRPT
0111 0110
xxxx xxxx
XXXX XXXX
—
Read Control Register
RCR
000a aaaa
xxxx xxxx
XXXX XXXX
XXXX XXXX
Write Control Register
WCR
010a aaaa
dddd dddd
DDDD DDDD
DDDD DDDD
Read Control Register Unbanked
RCRU
0010 0000
AAAA AAAA
xxxx xxxx
XXXX XXXX
Write Control Register Unbanked
WCRU
0010 0010
AAAA AAAA
dddd dddd
DDDD DDDD
Bit Field Set
BFS
100a aaaa
dddd dddd
DDDD DDDD
DDDD DDDD
Bit Field Clear
BFC
101a aaaa
dddd dddd
DDDD DDDD
DDDD DDDD
Bit Field Set Unbanked
BFSU
0010 0100
AAAA AAAA
dddd dddd
DDDD DDDD
Bit Field Clear Unbanked
BFCU
0010 0110
AAAA AAAA
dddd dddd
DDDD DDDD
Read EGPDATA
RGPDATA
0010 1000
xxxx xxxx
XXXX XXXX
XXXX XXXX
Write EGPDATA
WGPDATA
0010 1010
dddd dddd
DDDD DDDD
DDDD DDDD
Read ERXDATA
RRXDATA
0010 1100
xxxx xxxx
XXXX XXXX
XXXX XXXX
Write ERXDATA
WRXDATA
0010 1110
dddd dddd
DDDD DDDD
DDDD DDDD
Read EUDADATA
RUDADATA
0011 0000
xxxx xxxx
XXXX XXXX
XXXX XXXX
Write EUDADATA
WUDADATA
0011 0010
dddd dddd
DDDD DDDD
DDDD DDDD
Legend:
x/X = read data, d/D = write data, a = banked SFR address, A = unbanked SFR address. ‘X’ and ‘D’ are optional.
DS39935C-page 40
 2010 Microchip Technology Inc.
ENC424J600/624J600
4.3
Single Byte Instructions
4.3.1
The bank select opcodes, B0SEL, B1SEL, B2SEL and
B3SEL, switch the SFR bank to Bank 0, Bank 1, Bank 2
or Bank 3, respectively. The updated bank select state
is saved internally inside the ENCX24J600 in volatile
memory. Firmware can retrieve the currently selected
SFR bank state by using the Read Bank Select
(RBSEL) opcode.
All single byte instructions are designed to perform a
simple command that affects the ENCX24J600
device’s state. In most cases, they set or clear a small
number of control bits which would otherwise require
one or more N-byte opcodes to perform. None of these
instructions return any data to the host microcontroller.
Figure 4-1 shows the timing relationships for performing
a single byte operation. The opcode (‘11xxxxx0’) is
presented on the device’s SI pin starting with the Most
Significant bit of the opcode; the Least Significant bit is
always ‘0’. The SO pin is actively driven with
indeterminate ‘1’s or ‘0’s while the CS pin is driven low.
It continues to be driven until the CS pin is returned high.
The bank select opcodes are needed to access most
SFR addresses when using the RCR, WCR, BFS and
BFC instructions. These are discussed in more detail in
Section 4.6 “N-Byte Instructions”.
Upon device power-up or System Reset, Bank 0 is
automatically selected. After Reset, hardware does not
modify the bank state again. Any value programmed by
a BxSEL opcode is retained until the next BxSEL
opcode is executed or a System Reset is issued.
Because all single byte instructions are fixed length
with no optional parameters, it is possible to execute
any instruction immediately following the execution of
any single byte instruction without deasserting the chip
select line in between.
4.3.2
FC (FLOW CONTROL) OPCODES
The flow control opcodes, FCDISABLE, FCSINGLE,
FCMULTIPLE and FCCLEAR, all modify the device’s
Flow Control mode by changing the values of the
FCOP<1:0> bits (ECON1<7:6>). These opcodes
execute regardless of the currently selected SFR bank.
For more information on flow control operation, see
Section 11.0 “Flow Control”.
If the CS control signal is deactivated before the 8th bit
of the opcode is sent to the ENCX24J600, indeterminate
results will occur. In some cases, the instruction is
executed or partially executed. To avoid this, it is recommended that a single byte instruction should not be
interrupted. If it is unavoidable that an instruction gets
partially executed, have the application later reissue the
same instruction and let it complete to place the device
into a known state.
4.3.3
DMA OPCODES
The DMA opcodes, DMASTOP, DMACKSUM, DMACKSUMS,
DMACOPY and DMACOPYS, modify the operation of the
device’s DMA controller, all by simultaneously changing
the values of the DMAST, DMACPY, DMACSSD and
DMANOCS control bits (ECON1<5:2>). For more information on DMA operation, see Section 14.0 “Direct
Memory Access (DMA) Controller”.
There are a total of 20 single byte opcodes, which are
listed in Table 4-2. All single byte opcodes will operate
regardless of which SFR bank is selected at the time.
Those opcodes that affect multiple bits, or affect SFR
addressing, are detailed below.
FIGURE 4-1:
BxSEL OPCODES
SINGLE BYTE INSTRUCTION TIMING
CS
1
2
3
4
5
6
7
8
1
1
c5
c4
c3
c2
c1
0
x
x
x
SCK
SI
Opcode
SO
Hi-Z
x
 2010 Microchip Technology Inc.
x
x
x
x
x
Hi-Z
DS39935C-page 41
ENC424J600/624J600
TABLE 4-2:
SINGLE BYTE INSTRUCTIONS
Mnemonic
Opcode
Instruction
B0SEL
1100 0000 Selects SFR Bank 0
B1SEL
1100 0010 Selects SFR Bank 1
B2SEL
1100 0100 Selects SFR Bank 2
B3SEL
1100 0110 Selects SFR Bank 3
SETETHRST
1100 1010 Issues System Reset by setting ETHRST (ECON2<4>)
FCDISABLE
1110 0000 Disables flow control (sets ECON1<7:6> = 00)
FCSINGLE
1110 0010 Transmits a single pause frame (sets ECON1<7:6> = 01)
FCMULTIPLE
1110 0100 Enables flow control with periodic pause frames (sets ECON1<7:6> = 10)
FCCLEAR
1110 0110 Terminates flow control with a final pause frame (sets ECON1<7:6> = 11)
SETPKTDEC
1100 1100 Decrements PKTCNT by setting PKTDEC (ECON1<8>)
DMASTOP
1101 0010 Stops current DMA operation by clearing DMAST (ECON1<5>)
DMACKSUM
1101 1000 Starts DMA and checksum operation (sets ECON1<5:2> = 1000)
DMACKSUMS
1101 1010 Starts DMA checksum operation with seed (sets ECON1<5:2> = 1010)
DMACOPY
1101 1100 Starts DMA copy and checksum operation (sets ECON1<5:2> = 1100)
DMACOPYS
1101 1110 Starts DMA copy and checksum operation with seed (sets ECON1<5:2> = 1110)
SETTXRTS
1101 0100 Sets TXRTS (ECON1<1>), sends an Ethernet packet
ENABLERX
1110 1000 Enables packet reception by setting RXEN (ECON1<0>)
DISABLERX
1110 1010 Disables packet reception by clearing RXEN (ECON1<0>)
SETEIE
1110 1100 Enable Ethernet Interrupts by setting INT (ESTAT<15>)
CLREIE
1110 1110 Disable Ethernet Interrupts by clearing INT (ESTAT<15>)
4.4
Two-Byte Instructions
value (00h through 03h) is returned on the SO pin, MSb
first, while the second byte is being presented on the SI
pin.
There is only one instruction in the ENCX24J600 command set which uses two SPI bytes. The Read Bank
Select opcode, RBSEL, reads the internal SFR bank
select state and returns the value to the host controller.
Because this instruction is a fixed length with no
optional parameters, it is possible to execute any
instruction following the execution of RBSEL without
deasserting the chip select line in between.
Figure 4-2 shows the timing relationships for performing the two-byte operation. The first byte of the opcode
(‘11001000’) must be presented on the SI pin, MSb
first, followed by “don’t care” values for the second byte
(9th through 16th SCK rising edges). The bank select
FIGURE 4-2:
Since this opcode does not modify the ENCX24J600
internal state, it can be aborted at any time by returning
the CS pin to the inactive state.
TWO-BYTE INSTRUCTION TIMING (RBSEL OPCODE)
CS
1
2
3
4
5
6
7
8
1
1
0
0
1
0
0
0
9
10
11
12
13
14
15
16
d
d
SCK
SI
RBSEL Opcode
SO
Hi-Z
DS39935C-page 42
x
x
x
x
x
x
SFR Bank Select
x
x
0
0
0
0
0
0
x
Hi-Z
 2010 Microchip Technology Inc.
ENC424J600/624J600
4.5
Three-Byte Instructions
For write commands (shown in Figure 4-4), the opcode
byte (‘011xxx00’) must be presented on the SI line,
MSb first, followed immediately by the pointer data to
be written. Like the data returned during a read
operation, the write data must be presented MSb first,
Least Significant Byte first.
All three-byte instructions are designed to quickly read
or update the Read and Write Pointers used to access
the SRAM buffer area. Unlike the single byte instructions and RBSEL, each instruction in this group has
distinct read and write implementations.
If the application only needs to write to the lower byte of
a 16-bit pointer, it can optionally skip the upper byte by
raising chip select after the 16th clock pulse and allowing
adequate chip select hold time to elapse. The hardware
would then update the lower byte of the pointer while
maintaining the original value in the upper byte.
For read commands (shown in Figure 4-3), the opcode
byte (‘011xxx10’) must be presented on the SI pin,
MSb first, followed by “don’t care” values for the second
and third bytes (9th through 24th SCK rising edges).
Response data is returned on the SO line during the
second and third bytes.
During write operations, the device actively drives the
SO line while the chip select line is active. The value
during this interval is to be ignored.
Data on the SO line is also presented in MSb first bit
ordering. However, read commands are intended to
read a 16-bit pointer in little-endian byte ordering.
Therefore, the first byte on the SO line (returned during
SCK clocks, 9 through 16) is the lower byte of the 16-bit
pointer and is followed by the upper byte (returned
during SCK clocks 17 through 24).
All three-byte instructions, including read operations,
are considered to be finished at the end of the 24th
SCK clock (if reached). The host controller may issue
another SPI instruction or multiple fixed length
instructions without deasserting chip select.
Read operations do not affect the ENCX24J600
device’s internal state, and therefore, can be aborted at
any time by deasserting chip select.
FIGURE 4-3:
There are 12 three-byte instructions, which are divided
equally between read and write instructions. They are
listed in Table 4-3.
THREE-BYTE READ INSTRUCTION TIMING
CS
1
2
3
4
5
6
7
8
0
1
1 c4 c3 c2 1
0
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
SCK
SI
Opcode
SO
Hi-Z
x
FIGURE 4-4:
x
x
x
x
Read High Byte
(optional)
Read Low Byte
x
x
x d7 d6 d5 d4 d3 d2 d1 d0 D7 D6 D5 D4 D3 D2 D1 D0
x
Hi-Z
x
Hi-Z
THREE-BYTE WRITE INSTRUCTION TIMING
CS
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
0
1
1
c4 c3 c2 0
0
d7 d6 d5 d4 d3 d2 d1 d0 D7 D6 D5 D4 D3 D2 D1 D0
SCK
SI
Opcode
SO
Hi-Z
x
x
x
x
 2010 Microchip Technology Inc.
x
Write High Byte
(optional)
Write Low Byte
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
DS39935C-page 43
ENC424J600/624J600
TABLE 4-3:
Mnemonic
THREE-BYTE INSTRUCTIONS
Opcode
Argument
3rd Byte
Instruction
1st Byte
2nd Byte
WGPRDPT
0110 0000
dddd dddd
DDDD DDDD Write General Purpose Buffer Read Pointer
(EGPRDPT).
RGPRDPT
0110 0010
xxxx xxxx
XXXX XXXX Read General Purpose Buffer Read Pointer
(EGPRDPT).
WRXRDPT
0110 0100
dddd dddd
DDDD DDDD Write Receive Buffer Read Pointer (ERXRDPT).
RRXRDPT
0110 0110
xxxx xxxx
XXXX XXXX Read Receive Buffer Read Pointer (ERXRDPT).
WUDARDPT
0110 1000
dddd dddd
DDDD DDDD Write User-Defined Area Read Pointer (EUDARDPT).
RUDARDPT
0110 1010
xxxx xxxx
XXXX XXXX Read User-Defined Area Read Pointer (EUDARDPT).
WGPWRPT
0110 1100
dddd dddd
DDDD DDDD Write General Purpose Buffer Write Pointer
(EGPWRPT).
RGPWRPT
0110 1110
xxxx xxxx
XXXX XXXX Read General Purpose Buffer Write Pointer
(EGPWRPT).
WRXWRPT
0111 0000
dddd dddd
DDDD DDDD Write Receive Buffer Write Pointer (ERXWRPT).
RRXWRPT
0111 0010
xxxx xxxx
XXXX XXXX Read Receive Buffer Write Pointer (ERXWRPT).
WUDAWRPT
0111 0100
dddd dddd
DDDD DDDD Write User-Defined Area Write Pointer (EUDAWRPT).
RUDAWRPT
0111 0110
xxxx xxxx
XXXX XXXX Read User-Defined Area Write Pointer (EUDAWRPT).
Legend: x/d = pointer data (LSB), X/D = pointer data (MSB, optional).
DS39935C-page 44
 2010 Microchip Technology Inc.
ENC424J600/624J600
4.6
N-Byte Instructions
bank prior to their execution. Because of this, they
cannot be used for the unbanked SFR space (80h
through 9Fh).
N-byte instructions make up the most versatile class of
SPI commands, as they can read or write to any
addressable SFR or SRAM space. Their name comes
from their variable length nature; they require a minimum of two bytes, but can take an indefinite number of
bytes of data argument, or return an unlimited number
of output bytes. This makes them useful for reading or
writing entire arrays of data to or from the SRAM buffer.
Figure 4-5 shows the timing relationships for these
operations. Like all other opcodes, data must be
presented on the SI pin, MSb first. For all banked
instructions, the first byte of data must be the opcode,
comprised of a 3-bit prefix designating the instruction
and a 5-bit banked SFR address. If the instruction is a
write or bit field set/clear opcode, the next bytes are the
data or bit mask to be written. For read instructions, the
next bytes on the SI pin are “don’t care”.
Since these instructions are of an intrinsically variable
length, no other opcode may follow any N-byte
instruction until the CS line is driven high. Driving CS
high terminates the instruction and then places the SO
pin in a high-impedance state.
For write and bit field set/clear instructions, the SO pin
is actively driven with indeterminate ‘1’s or ‘0’s while
the CS pin is driven low. For read instructions, indeterminate data is clocked out on SO during SCK clocks,
1 through 8. Starting with the 9th clock, valid data is
clocked out byte-wise on SO, MSb first.
The format of the N-byte instructions differs depending
on if a read versus a write command is executed, and
if a banked SFR, unbanked SFR or SRAM location is
accessed. The differences are discussed in the
following sections.
4.6.1
As long as the CS pin is held low, clocks on SCK are
provided and data is presented on SI, the instruction
continues to execute indefinitely, automatically incrementing to the next register address in the SFR Bank
and writing data from SI to, or outputting data on SO
from, subsequent registers. When the end of a bank is
reached, the address automatically wraps back to the
beginning (00h) of the bank and continues; the
selected bank does not change.
BANKED SFR OPERATION
The N-byte Banked SFR instructions are WCR, RCR, BFS
and BFC. These instructions depend on the use of the
appropriate BxSEL instructions to select the proper SFR
FIGURE 4-5:
N-BYTE SPI INSTRUCTION TIMING (BANKED SFR OPERATIONS)
Write Operation
CS
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27
SCK
c7 c6 c5 a4 a3 a2 a1 a0 d7 d6 d5 d4 d3 d2 d1 d0 D7 D6 D5 D4 D3 D2 D1 D0 D7 D6 D5
SI
SO
Hi-Z
x
Write 2nd Byte
(optional)
Write 1st Byte
Opcode w/SFR Address
x
x
x
x
x
x
x
x
x
x
x
x
x
Additional
x
x
x
x
x
x
x
x
x
x
x
x
x
2
3
4
5
6
7
8
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27
Read Operation
CS
1
SCK
c7 c6 c5 a4 a3 a2 a1 a0
SI
Opcode w/SFR Address
SO
Hi-Z
x
x
x
 2010 Microchip Technology Inc.
x
x
x
x
Read 1st Byte
Read 2nd Byte
(optional)
Additional
x d7 d6 d5 d4 d3 d2 d1 d0 D7 D6 D5 D4 D3 D2 D1 D0 D7 D6 D5
DS39935C-page 45
ENC424J600/624J600
There are four banked SFR opcodes, summarized in
Table 4-4. Additional details for these opcodes are
provided below.
4.6.1.1
WCR Opcode
The Write Control Register (WCR) opcode byte consists
of the prefix, ‘010’, concatenated with the 5-bit banked
SFR address of the first register to write to. For
example, if Bank 3 were currently selected and the host
microcontroller wanted to write to the ECON2L register
at banked address 0Eh, the 8-bit opcode would be
‘01001110’ or 4Eh.
Generally, WCR can be executed on most register
addresses, in any sequence and for any length. An
important exception is when WCR is used on any MAC
or MII register. These registers must be written as a
whole 16-bit register, low byte first (e.g., MACON1
must be written by first writing to MACON1L, then
MACON1H). Writing only to the upper byte of a MAC or
MII register results in a successful write to the upper
register, while the lower register is written with indeterminate data. If a WCR instruction is aborted by raising
CS while writing to the upper byte of a MAC or MII
register, neither upper nor lower byte will be updated.
4.6.1.2
RCR Opcode
The Read Control Register (RCR) opcode byte consists
of the prefix, ‘000’, concatenated with the 5-bit banked
SFR address of the first register to read from. Using the
previous example, the 8-bit opcode to read ECON2L
would be ‘00001110’ or 0Eh.
Read operations can be performed against any register
address, in any sequence and for any length. However,
due to volatile register shadowing, it is recommended
that the ERXHEADH:ERXHEADL register pair be read
in sequence (low byte first) to obtain the correct value.
See Section 9.2 “Receiving Packets” for additional
information.
4.6.1.3
and automatic address increment, they behave almost
identically to the WCR opcode. However, instead of
absolute data to be written to a register, the host
microcontroller provides a bit mask showing which bits
of the target register need to be set or cleared.
For BFS, the ENCX24J600 performs a logical OR
operation with the supplied bit field causing ‘1’ bits in the
bit field to become set bits in the register; ‘0’ bits in the bit
field have no effect on the corresponding register bits. For
BFC, the ENCX24J600 performs a logical AND with the
complement of the supplied mask. This causes ‘1’ bits in
the mask to become clear bits in the register; ‘0’ bits in the
mask do not affect the corresponding register bits.
The host controller must use bit field operations when
attempting to change bits in a volatile control or interrupt
flag register. Normally, changing such a bit might be
accomplished
by
the
application
as
a
“read-modify-write” operation: reading the control register’s contents, modifying the register copy in memory on
the controller side and writing the modified register data
back to the ENCX24J600. In a dynamic environment,
however, one or more control bits may change state
between the read and write, resulting in an incorrect
device state after the write. As an example, assume that
the DMA module is in use (ECON1L<5> = 1) at the
same time that the application wants to transmit a packet
(i.e., setting ECON1L<1>). By the time a
read-modify-write on ECON1L is complete, the DMA
operation may have completed and cleared
ECON1L<5>. In this case, the write back erroneously
starts a new DMA operation.
Using BFS and BFC allows for bit level changes to one
or more control bits without the delay of a read and
write back. In the previous example, using BFS with a
bit mask of ‘00000010’ on ECON1L, sets ECON1L<1>
and starts a packet transmission without affecting the
status of ECON1L<5>.
Note:
BFS and BFC Opcodes
The Bit Field Set (BFS) and Bit Field Clear (BFC)
opcodes consist of the prefix, ‘100’ (for BFS) or ‘101’
(for BFC), concatenated with the 5-bit banked SFR
address of the first register to write to. In terms of timing
TABLE 4-4:
Unlike the WCR opcode, BFS and BFC
cannot be used to modify MAC or MII
registers. Never use these opcodes on
MAC and MII registers.
N-BYTE BANKED SFR INSTRUCTIONS
Instruction
Mnemonic
Opcode
Argument
1st Byte
2nd Byte
3rd Byte
Nth Byte
Read Control Register(s)
RCR
000a aaaa
xxxx xxxx
XXXX XXXX
XXXX XXXX
Write Control Register(s)
WCR
010a aaaa
dddd dddd
DDDD DDDD
DDDD DDDD
Bit Field(s) Set
BFS
100a aaaa
dddd dddd
DDDD DDDD
DDDD DDDD
Bit Field(s) Clear
BFC
101a aaaa
dddd dddd
DDDD DDDD
DDDD DDDD
Legend: x/X = read data (LSB/MSB), d/D = write data (LSB/MSB), a = banked SFR address.
DS39935C-page 46
 2010 Microchip Technology Inc.
ENC424J600/624J600
4.6.2
UNBANKED SFR OPERATIONS
byte-wise on SO, MSb first. As with three-byte
instructions, the lower byte of a data word is presented
first, followed by the upper byte.
The N-byte unbanked SFR instructions are WCRU,
RCRU, BFSU and BFCU. These instructions use an
opcode with a one-byte address argument and do not
depend on the use of BxSEL instructions for SFR bank
selection.
As long as the CS pin is held low, the instruction
continues to execute, automatically incrementing to the
next register address in the SFR space and writing data
from SI to, or outputting data on SO from, subsequent
registers. When the end of a bank is reached, the
address continues to the top of the next bank.
Addresses continue to increment through the banks
into the unbanked SFR area (addresses 80h through
9Fh), then wrap around to the start of Bank 0 (00h). The
SFR bank value used by the BxSEL and RBSEL
opcodes is not affected by the execution of unbanked
SFR instructions.
Figure 4-6 shows the timing relationships for these
operations. Like all other opcodes, data is presented on
the SI pin, MSb first. For this class of instructions, the
first byte of data is a specific opcode; the second byte
is the 8-bit absolute address of the target SFR. If the
instruction is a write or bit set/clear opcode, the next
bytes are the data or bit mask to be written. For read
instructions, the next bytes are don’t cares.
For write and bit set/clear instructions, the SO pin is
actively driven with indeterminate ‘1’s or ‘0’s while the
CS pin is driven low. For read instructions, random data
is clocked out on SO during SCK clocks, 1 through 16.
Starting with the 17th clock, data is clocked out
FIGURE 4-6:
There are four unbanked SFR opcodes, summarized in
Table 4-5. Except for addressing, the unbanked SFR
instructions are analogous to the banked SFR instructions. However, there are certain differences in their
behavior with certain pointer registers, as noted below.
N-BYTE SPI OPCODE (UNBANKED SFR OPERATIONS)
Write Operation
CS
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27
0
0
1
0
0 c2 c1 0 a7 a6 a5 a4 a3 a2 a1 a0 d7 d6 d5 d4 d3 d2 d1 d0 D7 D6 D5
SCK
SI
Opcode
SO
Hi-Z
x
Unbanked SFR Address
x
x
x
x
x
x
Write 1st Byte
x
x
x
x
x
x
x
Additional
x
x
x
x
x
x
x
x
x
x
x
x
x
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27
0
0
1
0
0 c2 c1 0 a7 a6 a5 a4 a3 a2 a1 a0
Read Operation
CS
SCK
SI
Opcode
SO
Hi-Z
x
x
x
 2010 Microchip Technology Inc.
x
x
Unbanked SFR Address
x
x
x
x
x
x
x
x
x
x
Read 1st Byte
Additional
x d7 d6 d5 d4 d3 d2 d1 d0 D7 D6 D5
DS39935C-page 47
ENC424J600/624J600
4.6.2.1
WCRU Opcode
The Write Control Register Unbanked (WCRU) opcode
starts with the opcode, ‘00100010’ (22h), followed by
the unbanked SFR register address during SPI clocks,
9 through 16. For example, to write to ECON2L at
address 6Eh, the instruction would be ‘22h 6Eh’,
followed by the data to be written.
When the host controller is finished writing data, it should
raise the CS line, putting the device in an inactive state
and preparing it for the next SPI instruction. When finishing a WCRU transaction, ensure that adequate CS hold
time is provided for the last write to complete before
raising CS.
Generally, WCRU can be executed on most register
addresses, in any sequence and for any length. An
important exception is when WCRU is used on any MAC
or MII register. These registers must be written as
whole 16-bit registers, low byte first (e.g., MACON1
must be written by first writing to MACON1L, then
MACON1H). Writing only to the upper byte of a MAC or
MII register results in a successful write to the upper
register, while the lower register is written with indeterminate data. If a WCRU instruction is aborted by raising
CS while writing to the upper byte of a MAC or MII
register, neither the upper nor lower byte will be
updated.
In addition, WCRU cannot be used to write to the SRAM
buffer virtual data windows (EGPDATA, ERXDATA and
EUDADATA). Writing to the buffer address indicated by
the corresponding address pointers’ attempts has no
effect on the memory location, and the pointers do not
auto-increment. To write to the SRAM buffer using the
virtual data windows, always use the SRAM buffer
opcodes (WGPDATA, WRXDATA and WUDADATA)
instead.
4.6.2.2
RCRU Opcode
Read operations can be performed on most register
addresses, in any sequence and for any length.
However, due to volatile register shadowing, it is
recommended that the ERXHEADH:ERXHEADL
register pair be read in sequence (low byte first) to
obtain the correct value. See Section 9.2 “Receiving
Packets” for additional information.
Similar to WCRU, RCRU cannot be used to read data
from the SRAM buffer using the virtual data windows.
Reading the buffer address indicated by the corresponding address pointers returns indeterminant data
and the pointers do not auto-increment. To read from
the buffer using the virtual data windows, always use
the SRAM buffer opcodes (RGPDATA, RRXDATA and
RUDADATA) instead.
4.6.2.3
The Bit Field Set Unbanked (BFSU) and Bit Filed Clear
Unbanked (BFCU) opcodes start with the opcode,
‘00100100’ (24h) for BFSU, or ‘00100110’ (26h) for
BFCU, followed by the unbanked SFR register address
during SPI clocks, 9 through 16. In terms of timing and
automatic address increment, they behave almost
identically to the WCRU opcode.
BFSU and BFCU function in the same manner as BFS
and BFC, by setting or clearing individual bits in the target register through the use of a bit mask. They are also
used in the same situations as BFS and BFC; namely,
when it is necessary to manipulate a single control bit
or interrupt flag in a dynamic situation, while avoiding
the disruption of other bits. See Section 4.6.1.3 “BFS
and BFC Opcodes” for a detailed explanation.
Note 1: Unlike WCRU, BFSU and BFCU cannot be
used to modify MAC or MII registers.
Never use these opcodes on MAC and
MII registers.
2: BFSU and BFCU opcodes have no effect
on any SFR in the unbanked region
(addresses 80h through 9Fh).
The Read Control Register Unbanked (RCRU) opcode
starts with the opcode, ‘00100000’ (20h), followed by
the unbanked SFR register address during SPI clocks,
9 through 16. Continuing the previous example, to read
ECON2L at address 6Eh, the complete two-byte
instruction would be ‘20h 6Eh’.
TABLE 4-5:
BFSU and BFCU Opcodes
N-BYTE UNBANKED SFR INSTRUCTIONS
Instruction
Mnemonic
Opcode
Argument
1st Byte
2nd Byte
3rd Byte
Nth Byte
Read Control Register(s), Unbanked
RCRU
0010 0000
AAAA AAAA
xxxx xxxx
XXXX XXXX
Write Control Register(s), Unbanked
WCRU
0010 0010
AAAA AAAA
dddd dddd
DDDD DDDD
Bit Field(s) Set, Unbanked
BFSU
0010 0100
AAAA AAAA
dddd dddd
DDDD DDDD
Bit Field(s) Clear, Unbanked
BFCU
0010 0110
AAAA AAAA
dddd dddd
DDDD DDDD
Legend:
x/X = read data (LSB/MSB), d/D = write data (LSB/MSB), A = unbanked SFR address. ‘X’ and ‘D’ are optional.
DS39935C-page 48
 2010 Microchip Technology Inc.
ENC424J600/624J600
4.6.3
SRAM BUFFER OPERATIONS
SO during SCK clocks, 1 through 8. Starting with the
9th clock, data is clocked out byte-wise on SO, MSb
first.
The six N-byte SRAM instructions function in a similar
manner to the banked SFR instructions, in that they use
a single byte opcode to define the operation and target
register. In terms of timing, they are virtually identical, as
shown in Figure 4-7.
As long as the CS pin is held low, the instruction
continues to execute, automatically incrementing to the
next SRAM address according to the pointer wrapping
rules described in Section 3.5.5 “Indirect SRAM Buffer
Access”. The associated read or write pointer SFRs are
automatically updated for each 8 SCK clocks. To
terminate the read or write operation, the CS signal must
be returned high.
Like all other opcodes, data is presented on the SI pin,
MSb first. For all instructions, the first byte of data is the
opcode. If the instruction is a write opcode, the next
bytes are the data to be written. For read instructions,
the next bytes are don’t cares.
There are 6 instructions divided equally between read
and write instructions. They are summarized in
Table 4-6.
For write instructions, the SO pin is actively driven with
indeterminate ‘1’s or ‘0’s while the CS pin is driven low.
For read instructions, random data is clocked out on
FIGURE 4-7:
N-BYTE SPI OPCODE (SRAM BUFFER OPERATIONS)
Write Operation
CS
1
2
3
4
5
6
7
0
0
1 c4 c3 c2 1
8
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27
SCK
SI
0 d7 d6 d5 d4 d3 d2 d1 d0 D7 D6 D5 D4 D3 D2 D1 D0 D7 D6 D5
Opcode
SO
Hi-Z
x
Write 2nd Byte
(optional)
Write 1st Byte
x
x
x
x
x
x
x
x
x
x
x
x
x
Additional
x
x
x
x
x
x
x
x
x
x
x
x
x
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27
0
0
1 c4 c3 c2 0
0
Read Operation
CS
SCK
SI
Opcode
SO
Hi-Z
x
x
x
 2010 Microchip Technology Inc.
x
x
Read 1st Byte
x
x
Read 2nd Byte
(optional)
Additional
x d7 d6 d5 d4 d3 d2 d1 d0 D7 D6 D5 D4 D3 D2 D1 D0 D7 D6 D5
DS39935C-page 49
ENC424J600/624J600
TABLE 4-6:
N-BYTE SRAM INSTRUCTIONS
Instruction
Mnemonic
Opcode
Argument
1st Byte
2nd Byte
3rd Byte
Nth Byte
Read Data from EGPDATA
RGPDATA
0010 1000
xxxx xxxx
XXXX XXXX
XXXX XXXX
Write Data from EGPDATA
WGPDATA
0010 1010
dddd dddd
DDDD DDDD
DDDD DDDD
Read Data from ERXDATA
RRXDATA
0010 1100
xxxx xxxx
XXXX XXXX
XXXX XXXX
Write Data from ERXDATA
WRXDATA
0010 1110
dddd dddd
DDDD DDDD
DDDD DDDD
Read Data from EUDADATA
RUDADATA
0011 0000
xxxx xxxx
XXXX XXXX
XXXX XXXX
Write Data from EUDADATA
WUDADATA
0011 0010
dddd dddd
DDDD DDDD
DDDD DDDD
Legend: x/X = read data (LSB/MSB), d/D = write data (LSB/MSB). ‘X’ and ‘D’ are optional.
DS39935C-page 50
 2010 Microchip Technology Inc.
ENC424J600/624J600
5.0
PARALLEL SLAVE PORT
INTERFACE (PSP)
ENC424J600/624J600 devices are designed to
interface directly with the parallel port available on
many microcontrollers, including the Parallel Master
Port (PMP) available on many Microchip PIC® microcontrollers. The Parallel Slave Port interface is highly
flexible, and can communicate using either Intel® or
Motorola® formats for read and write control strobes. In
the event that a parallel port is not available on the host
microcontroller, a software-managed parallel interface
derived from general purpose I/O pins can be used.
When the PSP interface is enabled, the ENCX24J600
functions as a slave device on the parallel bus. The
host controller must be configured to generate the
destination or target address on the slave device, as
well as the necessary port control signals.
5.1
Physical Implementation
The PSP interface is mutually exclusive with the serial
interface. To enable the PSP and disable the SPI, tie
the INT/SPISEL pin to Vss through an external resistor.
The PSP interface can use from 12 to 34 pins, depending on the device pin count and the PSP operating
mode. There are up to eight modes, covering the
permutations of data widths, data/address multiplexing
and bus strobe formats. The modes are selected by
TABLE 5-1:
In PSP mode, the CS/CS pin becomes the active-high
Chip Select (CS) pin. A weak internal pull-down is automatically connected to the pin when the PSP interface
is selected, preventing the pin from floating to an
indeterminate state when an external Chip Select
signal is absent.
When CS is in the inactive (logic-low) state, the AD15
(64-pin devices only) and AD<14:0> pins are placed in
a high-impedance state and are 5V tolerant. This
allows the ENCX24J600 to share a single parallel bus
with other slave devices that function the same way
while deselected. All other PSP pins, including the
A<14:0> pins (64-pin devices only) and the port control
strobes, are 5V tolerant inputs at all times. Inputs on
these pins are ignored while the chip select pin is at
logic low.
Unlike the SPI port, the use of chip select is optional
with the PSP. The CS pin can be tied permanently to
VDD if the parallel bus is not shared with other slave
devices. This saves one I/O pin from the host controller
while leaving the ENCX24J600 in a perpetually
selected state.
OPERATING MODES SUPPORTED BY THE PSP INTERFACE
Availability
PSP
Mode
tieing each of the PSPCFG<4:0> pins to either VDD or
VSS. The available combinations along with relative
performance metrics are summarized in Table 5-1.
Additional information on physical connections are
provided in Section 2.7.2 “PSP”.
44-pin 64-pin
# Pins(1)
Min
Max
Data
Width
Address/Data
Multiplexing
Theoretical
Performance
@ 10 MHz
(Mbit/s)
Control Lines
1
X
19
26
8 bit
No
CS, RD, WR
80
2
X
19
26
8 bit
No
CS, EN, R/W
80
3
X
26
34
16 bit
No
CS, RD, WRL, WRH
160
X
26
34
16 bit
No
CS, R/W, B0SEL, B1SEL
160
5
X
X
12
19
8 bit
Yes
AL, CS, RD, WR
<80
6
X
X
12
19
8 bit
Yes
AL, CS, EN, R/W
<80
4
9
X
19
21
16 bit
Yes
AL, CS, RD, WRL, WRH
<80
10
X
19
21
16 bit
Yes
AL, CS, R/W, B0SEL,
B1SEL
<80
Note 1:
Includes only address, data and port control strobes. INT/SPISEL and PSPCFG pins used for mode
configuration are not included.
 2010 Microchip Technology Inc.
DS39935C-page 51
ENC424J600/624J600
5.2
Using the PSP Interface
Unlike the serial interface, the PSP interface does not
use opcodes or a command architecture to control the
device. Instead, the memory space is accessed directly
using the addressing schemes described in
Section 3.1.2 “PSP Interface Maps”. Control SFRs
are read and written to directly, or manipulated through
their accompanying Bit Set and Bit Clear registers.
In 16-bit modes, each address (from 0 to 16,384) points
to a different word. The individual write high and write
low strobes allow the upper or lower byte of each word
to be written individually.
5.2.1
DIRECT AND INDIRECT SRAM
BUFFER ACCESS
Direct addressing allows the host controller to access
all SFRs and SRAM buffer addresses in the
ENCX24J600 memory space directly. This provides the
greatest flexibility and speed for accessing the SRAM
buffer. However, this configuration requires up to
15 address pins to be driven by the host controller. This
may be prohibitive in smaller, pin-constrained
applications.
In Modes 1 through 6, it is possible to conserve six
address pins by tying them to VDD. In this configuration,
only the addresses corresponding to the SFR area of
the memory space can be directly addressed. The
SRAM buffer memory can still be accessed, but only
through the EGPDATA, ERXDATA and EUDADATA
data windows in the SFR space, described in
Section 3.5.5 “Indirect SRAM Buffer Access”.
Indirect buffer access works well for Multiplexed
modes, such as PSP Modes 5, 6, 9 and 10. In these
modes, the auto-incrementing feature of the Data
Window Pointers allows access to the buffer at speeds
similar to byte-wise demultiplexed access, since a
separate address phase in not required for each byte.
The 8-Bit PSP modes have separate addresses for the
low and high bytes of each register. Since these
modes, therefore, have a “longer” memory space (i.e.,
more individual addresses), indirect access requires
9 lines to address all registers between 7E00h and
7FFFh. In contrast, the 16-bit modes require only
8 lines to address all of the registers in their SFR range
(3F00h to 3FFFh). Even so, using indirect access still
saves six pins in either data width: AD<14:9> in 8-bit
modes and AD<13:8> in 16-bit modes.
5.2.2
In 8-bit modes, the address latch is implemented on all
of the AD pins. In 16-bit modes, the address latch is
implemented for only the AD<13:0> pins. Because it
spans all required address lines, it is necessary to
present the desired address to the ENCX24J600 for
only a brief period while strobing the Address Latch
(AL) pin. On 8-bit interfaces, where AD<14:8> are used
exclusively for addressing, it is not necessary to drive
these upper address lines with a valid address
continually through read and write operations.
During operation, strobing the AL pin high and then low
causes the address presented on the AD pins to be
saved to the address latch. The address is retained for
all future read and write operations. It is retained until
either a POR event occurs or a subsequent write to the
address latch occurs by restrobing AL. This allows
multiple read and write requests to take place to the
same address, without requiring multiple address
latching operations.
The address latch does not auto-increment after
accesses. However, by using the indirect buffer access
method, it is possible to sequentially read or write an
entire array of sequential SRAM locations without
updating the address latch.
5.2.3
WRITE SELECT PINS
The 16-Bit PSP modes make use of either two write
pins (WRL and WRH), or a R/W select and two Byte
Lane (B0SEL and B1SEL) controls. When writing to the
device, these pins allow the host controller to instruct
whether to write only the low byte, only the high byte or
both bytes.
If only one write select pin is available on the host controller, the high and low selection pins may be tied
together to create a single 16-bit write strobe. When this
is done, only word writes are possible. However, the host
controller can still write single bytes when accessing the
SRAM buffer through the EGPDATA, ERXDATA or
EUDADATA Window registers, which always perform
8-bit accesses.
5.2.4
UNUSED INTERFACE PINS
Any unused PSP pins are placed in a high-impedance
state, regardless of the state of the CS pin. For
maximum ESD performance, it is recommended that
unused interface pins not be allowed to float. Instead, it
is recommended that unused interface pins be tied to
either VSS or VDD.
ADDRESS LATCHING
In Multiplexed Address/Data modes (PSP Modes 5
through 10), the ENCX24J600 implements an internal
address latch. This allows a reduction in the total number
of interface pins by multiplexing the data and addresses
that need to be communicated onto a single bus.
DS39935C-page 52
 2010 Microchip Technology Inc.
ENC424J600/624J600
5.2.5
PERFORMANCE
CONSIDERATIONS
When using a 16-bit data bus width, all registers and
direct access to SRAM can be accomplished through
16-bit accesses. Therefore, these modes are potentially twice as fast as their 8-bit equivalent parallel
mode.
However,
accesses
through
the
hardware-managed SRAM read/write registers,
EGPDATA, ERXDATA and EUDADATA, are always
8-bit regardless of the interface used. Therefore, in
many applications, it will not be practically feasible to
transfer 16 bits of meaningful data for all bus transfer
cycles.
When reading from the EGPDATA, ERXDATA and
EUDADATA registers on an interface with a multiplexed address bus, it is possible to latch the address
only once and then perform back-to-back reads or
writes without performing additional address latch
cycles. This can provide a significant performance
improvement when sequentially reading or writing an
array of data to/from the RAM. Due to this benefit, 8-Bit
Multiplexed modes (Modes 5 and 6) approach the
theoretical performance of the Demultiplexed PSP
Modes 1 and 2.
5.3
PSP Modes
The eight PSP modes are selected using the PSPCFG
pins. The address/data bus and port control connections differ between the modes, sometimes
significantly, as do the timing relationships between
address/data and control signals. Each of the modes is
described in detail in the following sections.
5.3.1
MODE 1
PSP Mode 1 is an 8-bit, fully demultiplexed mode that
is available on 64-pin devices only. The parallel interface consists of 8 bi-directional data pins (AD<7:0>)
and 9 to 15 separate address pins (A<14:0>). To select
PSP Mode 1, tie PSPCFG2, PSPCFG3 and PSPCFG4
to VSS. Figure 5-1 shows the connections required.
This mode uses active-high Read and Write strobes
(RD and WR) in conjunction with a Chip Select (CS)
signal. These three pins allow the host to select the
device, then signal when a read operation is desired or
when valid data is being presented to be written. The
AD<7:0> pins stay in a high-impedance state any time
CS or RD is low.
To perform a read operation:
1.
2.
3.
Raise the CS line (if connected to the host).
Present the address to be read onto the address
bus.
Raise the RD strobe and wait the required time
for the access to occur.
When RD is raised high, the data bus begins to drive
out indeterminate data for a brief period, then switches
to the correct read data after the appropriate read
access time has elapsed. When the RD strobe is
lowered, AD<7:0> return to a high-impedance state.
To perform a write operation:
1.
2.
3.
4.
Raise the CS line (if connected to the host).
Present the address onto the address bus.
Present the data on the data bus.
Strobe the WR signal high and then low.
For proper operation, do not raise RD and WR
simultaneously while the ENCX24J600 is selected.
Sample timing diagrams for reading and writing data in
this mode are provided in Figure 5-2 and Figure 5-3,
respectively.
 2010 Microchip Technology Inc.
DS39935C-page 53
ENC424J600/624J600
FIGURE 5-1:
DEVICE CONNECTIONS FOR PSP MODE 1
Host MCU
ENC624J600
CS(1)
RD
WR
PMCSx
PMRD
PMWR
6
PMA<14:9>
PMA<8:0>
8
PMD<7:0>
INTx
A<14:9>(2)
A<8:0>
9
AD<7:0>
(3)
INT/SPISEL
100 k
PSPCFG2
PSPCFG3
PSPCFG4
Note 1:
Use of the CS strobe from the controller is optional. If not used, tie CS to VDD.
2:
Connect these pins when direct addressing of the entire SRAM buffer is required. Tie to VDD when only indirect
addressing is desired.
3:
Use of the external interrupt signal to the controller is optional.
FIGURE 5-2:
MODE 1 READ OPERATION TIMING (TWO BYTES)
CS
RD
TPSP1
TPSP4
WR
Address<14:0>
A<14:0>
Hi-Z
AD<7:0>
Data<7:0>
TPSP2
FIGURE 5-3:
Address<14:0>
Hi-Z
Data<7:0>
Hi-Z
TPSP3
MODE 1 WRITE OPERATION TIMING (TWO BYTES)
CS
TPSP5
RD
WR
TPSP8
A<14:0>
AD<7:0>
DS39935C-page 54
TPSP6 Address<14:0>
Hi-Z
TPSP7
Data<7:0>
TPSP11
TPSP9
Address<14:0>
TPSP10
Data<7:0>
Hi-Z
 2010 Microchip Technology Inc.
ENC424J600/624J600
5.3.2
MODE 2
To perform a read operation:
PSP Mode 2 is also an 8-bit, fully demultiplexed mode
that is available on 64-pin devices only. The parallel
interface consists of 8 bidirectional data pins (AD<7:0>)
and 9 to 15 separate address pins (A<14:0>). To select
PSP Mode 2, tie PSPCFG2 and PSPCFG3 to VSS,
while connecting PSPCFG4 to VDD. Figure 5-4
demonstrates connections required to use Mode 2.
1.
2.
3.
This mode uses a combined Read/Write (R/W) select,
an Enable (EN) strobe pin and a separate Chip Select
pin (CS). These three pins allow the host to select the
device, indicate whether a read or write operation is
desired and signal when valid data is being presented
When EN is raised high, the data bus begins to drive
out indeterminate data for a brief period, then switches
to the correct read data after the appropriate read
access time has elapsed. When the EN strobe is lowered, the data bus pins return to a high-impedance
state.
4.
5.
A logic high signal on the R/W pin indicates that a read
operation is to be performed when the EN strobe is
asserted, while a logic low indicates that a write operation is to be performed. The state of R/W only affects
the data bus state when the EN signal is active. When
either CS, EN or R/W is driven low, the data bus stays
in a high-impedance state.
Raise the CS line (if connected to the host).
Raise the R/W signal.
Present the address to be read onto the address
bus.
Raise the EN strobe.
Wait the required time for the access to occur.
To perform a write operation:
1.
2.
3.
4.
5.
Raise the CS line (if connected to the host).
Lower the R/W signal.
Present the address onto the address bus.
Present the data on the data bus.
Strobe the EN signal high and then low.
Sample timing diagrams for reading and writing data in
this mode are provided in Figure 5-5 and Figure 5-6,
respectively.
FIGURE 5-4:
DEVICE CONNECTIONS FOR PSP MODE 2
Host MCU
ENC624J600
CS(1)
R/W
EN
PMCSx
PMRD/PMWR
PMENB
PMA<14:9>
PMA<8:0>
6
8
PMD<7:0>
INTx
A<14:9>(2)
A<8:0>
9
AD<7:0>
(3)
INT/SPISEL
+3.3V
100 k
PSPCFG2
PSPCFG3
PSPCFG4
Note 1:
Use of the CS strobe from the controller is optional. If not used, tie CS to VDD.
2:
Connect these pins when direct addressing of the entire SRAM buffer is required. Tie to VDD when only indirect
addressing is desired.
3:
Use of the external interrupt signal to the controller is optional.
 2010 Microchip Technology Inc.
DS39935C-page 55
ENC424J600/624J600
FIGURE 5-5:
MODE 2 READ OPERATION TIMING (TWO BYTES)
CS
R/W
EN
TPSP1
A<14:0>
AD<7:0>
TPSP4
Address<14:0>
Hi-Z
Data<7:0>
TPSP2
FIGURE 5-6:
Address<14:0>
Hi-Z
Data<7:0>
Hi-Z
TPSP3
MODE 2 WRITE OPERATION TIMING (TWO BYTES)
CS
TPSP5
R/W
EN
TPSP8
A<14:0>
AD<7:0>
DS39935C-page 56
TPSP6 Address<14:0>
Hi-Z
TPSP7
Data<7:0>
TPSP11
TPSP9
Address<14:0>
TPSP10
Data<7:0>
Hi-Z
 2010 Microchip Technology Inc.
ENC424J600/624J600
5.3.3
MODE 3
When RD is raised high, the data bus begins driving out
indeterminate data for a brief period, then switches to
the correct read data after the appropriate read access
time has elapsed. When the RD strobe is lowered, the
data pins will return to a high-impedance state.
PSP Mode 3 is a 16-bit, fully demultiplexed mode that
is available on 64-pin devices only. The parallel interface consists of 16 bidirectional data pins (AD<15:0>)
and 8 to 14 separate address pins (A<13:0>). To select
PSP Mode 3, tie PSPCFG3 and PSPCFG4 to VSS,
while connecting PSPCFG2 to VDD. Figure 5-7 shows
the connections required.
The device always outputs a full 16 bits of data for each
read request. If only 8 bits of data are required, read the
data from the correct pins (AD<15:8> or AD<7:0>) and
discard the remaining byte.
An active-high RD strobe and two Write strobes (WRH
and WRL) are utilized in conjunction with a separate
Chip Select (CS). These four pins allow the host to
select the device, then signal when a read operation is
desired or when valid data is being presented to be
written on either the low byte, high byte or both. For
proper operation, do not assert CS and RD while
simultaneously asserting either WRL or WRH.
To perform a write operation:
1.
2.
3.
In PSP Mode 3, AD<15:0> stay in a high-impedance
state any time CS or RD are low.
4.
To perform a read operation:
1.
2.
3.
5.
Raise the CS line (if connected to the host).
Present the address to be read onto the address
bus.
Raise the RD strobe and wait the required time
for the access to occur.
FIGURE 5-7:
Raise the CS line (if connected to the host).
Present the address onto the A<13:0> address
bus.
If writing to the low byte of the memory location,
present the data on AD<7:0>, and strobe the
WRL signal high and then low.
If writing to the high byte, present the data on the
AD<15:8> and strobe the WRH signal.
If writing a whole word, strobe both WRL and
WRH simultaneously.
Sample timing diagrams for reading and writing data in
this mode are provided in Figure 5-8 and Figure 5-9,
respectively.
DEVICE CONNECTIONS FOR PSP MODE 3
Host MCU
ENC624J600
PMCSx
PMRD
PMWRL
PMWRH
PMA<13:8>
PMA<7:0>
PMD<15:0>
CS(1)
RD
WRL
WRH(2)
(2)
6
A<13:8>(3)
A<7:0>
8
16
AD<15:0>
INTx(4)
INT/SPISEL
+3.3V
100 k
PSPCFG2
PSPCFG3
PSPCFG4
Note 1:
Use of the CS strobe from the controller is optional. If not used, tie CS to VDD.
2:
WRL and WRH may optionally be tied together to form a 16-bit write strobe. See Section 5.2.3 “Write Select
Pins” for details.
3:
Connect these pins when direct addressing of the entire SRAM buffer is required. Tie to VDD when only indirect
addressing is desired.
4:
Use of the external interrupt signal to the controller is optional.
 2010 Microchip Technology Inc.
DS39935C-page 57
ENC424J600/624J600
FIGURE 5-8:
MODE 3 READ OPERATION TIMING (FOUR BYTES)
CS
RD
TPSP1
TPSP4
WRL
WRH
Address<13:0>
A<13:0>
Hi-Z
AD<15:0>
Data<15:0>
TPSP2
FIGURE 5-9:
Address<13:0>
Hi-Z
Data<15:0>
Hi-Z
TPSP3
MODE 3 WRITE OPERATION TIMING (THREE BYTES)
CS
TPSP5
RD
WRL
TPSP8
TPSP11
WRH
A<13:0>
AD<15:0>
DS39935C-page 58
TPSP6 Address<13:0>
Hi-Z
TPSP7
Data<15:0>
TPSP9
Address<13:0>
TPSP10
Data<7:0>
Hi-Z
 2010 Microchip Technology Inc.
ENC424J600/624J600
5.3.4
MODE 4
4.
When either BxSEL pin is raised high, the data bus
begins driving out indeterminate data for a brief period,
then switches to the correct read data after the appropriate read access time has elapsed. When B0SEL and
B1SEL are both low, the data bus pins return to a
high-impedance state.
PSP Mode 4 is also a 16-bit, fully demultiplexed mode
that is available in 64-pin devices only. When using
PSP Mode 4, the parallel interface consists of
16 bidirectional data pins (AD<15:0>) and 8 to 14 separate address pins (A<13:0>). To select PSP Mode 4,
tie PSPCFG2 and PSPCFG4 to VDD, while connecting
PSPCFG3 to VSS. Figure 5-10 shows the connections
required.
The device always outputs a full 16 bits of data for each
read request, even if only one byte select is strobed. If
only 8 bits of data are required, read the data from the
correct pins (AD<15:8> or AD<7:0>) and discard the
remaining byte.
This mode uses a combined Read/Write (R/W) select,
two Byte Select (B0SEL and B1SEL) lines and a separate Chip Select (CS) signal. These four pins allow the
host to select the device, indicate whether a read or
write operation is desired and signal when valid data is
being presented for writing on either the low byte, high
byte or both.
To perform a write operation:
1.
2.
3.
4.
A logic-high signal on R/W indicates that a read operation is to be performed when either the B0SEL or
B1SEL strobe is asserted, while a logic low signal
indicates that a write operation is to be performed. The
state of R/W only affects the data bus state when either
B0SEL or B1SEL is active. When CS is driven low, R/W
is driven low, or both B0SEL and B1SEL are driven low
and the data bus stays in a high-impedance state.
5.
6.
To perform a read operation:
1.
2.
3.
Raise the CS line (if connected to the host).
Lower R/W.
Present the address onto the address bus.
If writing to the low byte of the memory location,
present the data on the AD<7:0>; then strobe
B0SEL high, then low.
If writing to the high byte, present the data on
AD<15:8> and strobe B1SEL.
If writing a whole word, strobe both B0SEL and
B1SEL simultaneously.
Sample timing diagrams for reading and writing data in
this mode are provided in Figure 5-11 and Figure 5-12,
respectively.
Raise the CS line (if connected to the host).
Raise the R/W signal.
Present the address to be read onto the address bus.
FIGURE 5-10:
Raise one or both byte select strobes.
DEVICE CONNECTIONS FOR PSP MODE 4
Host MCU
ENC624J600
PMCSx
PMRD/PMWR
PMENB0
PMENB1
CS(1)
R/W
B0SEL
B1SEL(2)
(2)
6
PMA<13:8>
PMA<7:0>
A<13:8>(3)
A<7:0>
8
16
PMD<15:0>
AD<15:0>
INTx(4)
INT/SPISEL
+3.3V
100 k
Note 1:
PSPCFG2
PSPCFG3
PSPCFG4
Use of the CS strobe from the controller is optional. If not used, tie CS to VDD.
2:
B0SEL and B1SEL may optionally be tied together to form a 16-bit write strobe. See Section 5.2.3 “Write
Select Pins” for details.
3:
Connect these pins when direct addressing of the entire SRAM buffer is required. Tie to VDD when only indirect
addressing is desired.
4:
Use of the external interrupt signal to the controller is optional.
 2010 Microchip Technology Inc.
DS39935C-page 59
ENC424J600/624J600
FIGURE 5-11:
MODE 4 READ OPERATION TIMING (FOUR BYTES)
CS
R/W
B0SEL
T PSP1
TPSP4
B1SEL
A<13:0>
AD<15:0>
Address<13:0>
Hi-Z
Data<15:0>
TPSP2
FIGURE 5-12:
Address<13:0>
Hi-Z
Data<15:0>
Hi-Z
TPSP3
MODE 4 WRITE OPERATION TIMING (THREE BYTES)
CS
TPSP5
R/W
B0SEL
TPSP8
TPSP11
B1SEL
TPSP6 Address<13:0>
A<13:0>
AD<15:0>
DS39935C-page 60
Hi-Z
TPSP7
Data<15:0>
TPSP9
Address<13:0>
TPSP10
Data<7:0>
Hi-Z
 2010 Microchip Technology Inc.
ENC424J600/624J600
5.3.5
MODE 5
To perform a write operation:
PSP Mode 5 is an 8-bit, partially multiplexed mode that
is available on all devices. The parallel interface consists of 8 multiplexed address and data pins (AD<7:0>),
plus one required high address bit (AD8) and 6 optional
address-only pins (AD<14:9>).
1.
2.
3.
4.
Raise CS (if connected to the host).
Present the address to write to on AD<14:0>.
Strobe the AL pin.
Change the data on AD<7:0> from the lower
address byte to the data to be written.
Strobe WR high and then low.
Selecting PSP Mode 5 differs between 44-pin and
64-pin devices, as shown in Figure 5-13. For the 44-pin
ENC424J600, tie PSPCFG0 to VSS. For the 64-pin
ENC624J600, tie PSPCFG1 and PSPCFG2 to VSS,
and PSPCFG3 to VDD.
5.
This mode uses active-high Read and Write (RD and
WR) strobes, as well as separate Chip Select and
Address Latch (CS and AL) lines. These four pins allow
the host to select the device, latch an address, then
indicate when a read or write operation is desired. For
proper operation, treat the RD, WR and AL strobes as
mutually exclusive whenever the ENCX24J600 is
selected. Only raise one of these to logic high at any
given time.
Sample timing diagrams for reading and writing data in
this mode are provided in Figure 5-14 and Figure 5-15,
respectively.
If a subsequent read or write of the same memory
address is desired, it is possible to restrobe RD or WR
without going through another address latch cycle.
AD<14:8> are used as address inputs only, and are
therefore, always left in a high-impedance state. When
CS or RD is driven low, the multiplexed AD<7:0> pins
stay in a high-impedance state.
To perform a read operation:
1.
2.
3.
4.
5.
Raise CS (if connected to the host).
Present the address to read from on AD<14:0>.
Strobe the AL pin high and low.
Set the host controller’s AD<7:0> bus pins as
inputs.
Raise RD.
The AD<7:0> bus begins driving out indeterminate data
for a brief period, then switches to the correct read data
after the appropriate read access time has elapsed.
When RD is lowered, the AD<7:0> pins return to a
high-impedance state.
 2010 Microchip Technology Inc.
DS39935C-page 61
ENC424J600/624J600
FIGURE 5-13:
44-pin Devices:
DEVICE CONNECTIONS FOR PSP MODE 5
Host MCU
ENC424J600
PMCSx
PMRD
PMWR
PMALL
PMA<14:9>
PMA8
PMD<7:0>
CS(1)
RD
WR
AL
6
AD<14:9>(2)
AD8
AD<7:0>
8
INTx(3)
INT/SPISEL
100 k
PSPCFG0
64-pin Devices:
Host MCU
ENC624J600
(1)
CS
RD
WR
AL
PMCSx
PMRD
PMWR
PMALL
PMA<14:9>
PMA8
PMD<7:0>
6
AD<14:9>(2)
AD8
AD<7:0>
8
INTx(3)
INT/SPISEL
+3.3V
100 k
PSPCFG1
PSPCFG2
PSPCFG3
Note 1:
Use of the CS strobe from the controller is optional. If not used, tie CS to VDD.
2:
Connect these pins when direct addressing of the entire SRAM buffer is required. Tie to VDD when only indirect
addressing is desired.
3:
Use of the external interrupt signal to the controller is optional.
DS39935C-page 62
 2010 Microchip Technology Inc.
ENC424J600/624J600
FIGURE 5-14:
MODE 5 READ OPERATION TIMING (TWO BYTES – SAME ADDRESS)
CS
TPSP12
RD
TPSP4
WR
AL
TPSP13
AD<14:9>(1)
Address<14:9>
AD8(1)
AD<7:0>
TPSP15
Address<8>
Hi-Z
Address<7:0>
TPSP12
Data<7:0>
TPSP2
Hi-Z
Data<7:0>
Hi-Z
TPSP3
TPSP14
Note 1: AD8 must be driven by the host controller. AD<14:9> may be tied to logic high when only indirect access is desired.
FIGURE 5-15:
MODE 5 WRITE OPERATION TIMING (TWO BYTES – SAME ADDRESS)
CS
TPSP12
RD
WR
TPSP8
AL
TPSP13
AD<14:9>(1)
Address<14:9>
AD8(1)
AD<7:0>
TPSP11
Address<8>
Hi-Z
Address<7:0>
TPSP12
Data<7:0>
Data<7:0>
Hi-Z
TPSP7
TPSP14
TPSP10
Note 1: AD8 must be driven by the host controller. AD<14:9> may be tied to logic high when only indirect access is desired.
 2010 Microchip Technology Inc.
DS39935C-page 63
ENC424J600/624J600
5.3.6
MODE 6
To perform a read operation:
PSP Mode 6 is also an 8-bit, partially multiplexed mode
that is available on all devices. The parallel interface
consists of 8 multiplexed address and data pins
(AD<7:0>), plus one required high address bit (AD8)
and 6 optional address-only pins (AD<14:9>).
1.
2.
3.
4.
Selecting PSP Mode 6 differs between 44-pin and
64-pin devices, as shown in Figure 5-16. For the 44-pin
ENC424J600, tie PSPCFG0 to VDD. For the 64-pin
ENC624J600, tie PSPCFG1 and PSPCFG3 to VDD,
and PSPCFG2 to VSS.
5.
6.
This mode uses a combined Read/Write (R/W) select,
an Enable (EN) strobe and separate Chip Select (CS)
and Address Latch (AL) lines. These four pins allow the
host to select the device, latch an address, select either
a read or write operation, then assert the Enable pin
when a read is requested or the data to be written is
valid. For proper operation, do not assert EN and AL
simultaneously while the ENCX24J600 is selected.
AD<14:8> are used as address inputs only, and are
therefore, always left in a high-impedance state. When
CS, R/W or EN is driven low, the multiplexed AD<7:0>
pins stay in a high-impedance state.
Raise CS (if connected to the host).
Present the address to read from on AD<14:0>.
Strobe AL high and then low.
Set the host controller’s AD<7:0> bus pins as
inputs.
Raise R/W.
Raise the EN strobe.
The AD<7:0> bus begins driving out indeterminate data
for a brief period, then switches to the correct read data
after the appropriate read access time has elapsed.
When EN is lowered, the multiplexed AD<7:0> pins
return to a high-impedance state.
To perform a write operation:
1.
2.
3.
4.
5.
6.
Raise CS (if connected to the host).
Present the address to write to on AD<14:0>.
Strobe AL.
Lower R/W.
Change the data on AD<7:0> from the lower
address byte to the data to be written.
Strobe EN high, then low.
If a subsequent read or write of the same memory
address is desired, it is possible to restrobe EN without
going through another address latch cycle.
Sample timing diagrams for reading and writing data in
this mode are provided in Figure 5-17 and Figure 5-18,
respectively.
DS39935C-page 64
 2010 Microchip Technology Inc.
ENC424J600/624J600
FIGURE 5-16:
DEVICE CONNECTIONS FOR PSP MODE 6
44-pin Devices:
Host MCU
ENC424J600
PMCSx
PMRD/PMWR
PMENB
PMALL
PMA<14:9>
PMA8
PMD<7:0>
CS(1)
R/W
EN
AL
6
AD<14:9>(2)
AD8
AD<7:0>
8
INTx(3)
INT/SPISEL
+3.3V
100 k
PSPCFG0
64-pin Devices:
Host MCU
ENC624J600
CS(1)
R/W
EN
AL
PMCSx
PMRD/PMWR
PMENB
PMALL
PMA<14:9>
PMA8
PMD<7:0>
6
AD<14:9>(2)
AD8
AD<7:0>
8
INTx(3)
INT/SPISEL
+3.3V
100 k
Note 1:
PSPCFG1
PSPCFG2
PSPCFG3
Use of the CS strobe from the controller is optional. If not used, tie CS to VDD.
2:
Connect these pins when direct addressing of the entire SRAM buffer is required. Tie to VDD when only indirect
addressing is desired.
3:
Use of the external interrupt signal to the controller is optional.
 2010 Microchip Technology Inc.
DS39935C-page 65
ENC424J600/624J600
FIGURE 5-17:
MODE 6 READ OPERATION TIMING (TWO BYTES – SAME ADDRESS)
CS
T PSP12
R/W
T PSP1
EN
T PSP4
AL
T PSP13
AD<14:9> (1)
Address<14:9>
AD8 (1)
AD<7:0>
T PSP15
Address<8>
Hi-Z
Address<7:0>
Data<7:0>
T PSP12
T PSP2
Hi-Z
Data<7:0>
Hi-Z
T PSP3
T PSP14
Note 1: AD8 must be driven by the host controller. AD<14:9> may be tied to logic high when only indirect access is desired .
FIGURE 5-18:
MODE 6 WRITE OPERATION TIMING (TWO BYTES – SAME ADDRESS)
CS
T PSP12
R/W
T PSP5
EN
T PSP8
AL
T PSP13
AD<14:9> (1)
Address<14:9>
AD8 (1)
AD<7:0>
T PSP11
Address<8>
Hi-Z
Address<7:0>
T PSP12
Data<7:0>
Data<7:0>
Hi-Z
T PSP7
T PSP14
T PSP10
Note 1: AD8 must be driven by the host controller. AD<14:9> may be tied to logic high when only indirect access is desired .
DS39935C-page 66
 2010 Microchip Technology Inc.
ENC424J600/624J600
5.3.7
MODE 9
The AD<15:0> bus begins driving out indeterminate
data for a brief period, then switches to the correct read
data after the appropriate read access time has
elapsed. When RD is lowered, the AD<15:0> pins
return to a high-impedance state.
PSP Mode 9 is a 16-bit, fully-multiplexed mode that is
available on 64-pin devices only. The parallel interface
consists of 16 bidirectional data pins (AD<15:0>); the
lower 14 (AD<13:0>) also function as address pins. To
select PSP Mode 9, tie PSPCFG2 and PSPCFG3 to
VDD, while connecting PSPCFG1 to VSS. Figure 5-19
shows the connections required.
The device always outputs a full 16 bits of data for each
read request. If only 8 bits of data are required, read the
data from the correct pins (AD<15:8> or AD<7:0>) and
discard the remaining byte.
This mode uses an active-high Read (RD) strobe and
two Write (WRH and WRL) strobes in conjunction with
separate Chip Select (CS) and Address Latch (AL)
inputs. These five pins allow the host to select the
device, latch an address and then signal when a read
operation is desired or when valid data is being
presented to be written to either the low byte, high byte
or both. For proper operation while the ENCX24J600 is
selected, do not assert RD or AL while simultaneously
asserting either WRL or WRH.
To perform a write operation:
1.
2.
3.
4.
5.
AD<15:0> stay in a high-impedance state any time CS
or RD is low.
6.
To perform a read operation:
1.
2.
3.
4.
5.
If a subsequent read or write of the same memory
address is desired, it is possible to restrobe RD, WRL
or WRH without going through another address latch
cycle.
Raise CS (if connected to the host).
Present the address to read from on AD<13:0>.
Strobe AL high, then low.
Set the host controller’s AD<15:0> bus pins as
inputs.
Raise RD.
FIGURE 5-19:
Raise CS (if connected to the host).
Present the address to write to on AD<13:0>.
Strobe AL.
If writing to the low byte of the memory location,
present the data on AD<7:0>, then strobe WRL
high, then low.
If writing to the high byte, present the data on
AD<15:8>, then strobe WRH.
If writing a whole word, strobe both WRL and
WRH simultaneously.
Sample timing diagrams for reading and writing data in
this mode are provided in Figure 5-20 and Figure 5-21,
respectively.
DEVICE CONNECTIONS FOR PSP MODE 9
Host MCU
PMCSx
PMRD
PMWRL
PMWRH
PMALL
ENC624J600
CS(1)
RD
WRL
WRH(2)
AL
(2)
16
AD<15:0>
PMD<15:0>
INTx(3)
INT/SPISEL
+3.3V
100 k
PSPCFG1
PSPCFG2
PSPCFG3
Note 1:
Use of the CS strobe from the controller is optional. If not used, tie CS to VDD.
2:
WRL and WRH may optionally be tied together to form a 16-bit write strobe. See Section 5.2.3 “Write Select
Pins” for details.
3:
Use of the external interrupt signal to the controller is optional.
 2010 Microchip Technology Inc.
DS39935C-page 67
ENC424J600/624J600
FIGURE 5-20:
MODE 9 READ OPERATION TIMING (FOUR BYTES – SAME ADDRESS)
CS
TPSP12
RD
TPSP4
WRL
WRH
AL
AD<15:0>
TPSP13
Hi-Z
Address<13:0>
TPSP12
FIGURE 5-21:
TPSP15
TPSP14
Data<15:0>
TPSP2
Hi-Z
Data<15:0>
Hi-Z
TPSP3
MODE 9 WRITE OPERATION TIMING (THREE BYTES – SAME ADDRESS)
CS
TPSP12
RD
WRL
TPSP8
TPSP11
WRH
AL
AD<15:0>
TPSP13
Hi-Z
Address<13:0>
TPSP12
DS39935C-page 68
TPSP14
Data<15:0>
TPSP7
Data<7:0>
Hi-Z
TPSP10
 2010 Microchip Technology Inc.
ENC424J600/624J600
5.3.8
MODE 10
When either BxSEL pin is raised high, the AD<15:0>
bus begins driving out indeterminate data for a brief
period, then switches to the correct read data after the
appropriate read access time has elapsed. When
B0SEL and B1SEL are both low, AD<15:0> return to a
high-impedance state.
PSP Mode 10 is also a 16-bit, fully-multiplexed mode
that is available on 64-pin devices only. The parallel
interface consists of 16 bidirectional data pins
(AD<15:0>); the lower 14 (AD<13:0>) also function as
address pins. To select PSP Mode 10, tie PSPCFG1,
PSPCFG2 and PSPCFG3 to VDD. Figure 5-22 shows
the connections required.
The device always outputs a full 16 bits of data for each
read request, even if only one byte select is strobed. If
only 8 bits of data are required, read the data from the
correct pins (AD<15:8> or AD<7:0>) and discard the
remaining byte.
This mode uses an active-high Read/Write (R/W)
select and two Byte Select (B0SEL and B1SEL)
strobes in conjunction with separate Chip Select (CS)
and Address Latch (AL) inputs. These five pins allow
the host to select the device, latch an address, select
either a read or write operation, then assert the proper
Byte Select strobe(s) to perform the operation.
To perform a write operation:
1.
2.
3.
4.
5.
A logic high signal on the R/W pin indicates that a read
operation is to be performed when either the B0SEL or
B1SEL strobe is asserted, while a logic low signal
indicates that a write operation is to be performed. For
proper operation while the ENCX24J600 is selected,
the host controller should not assert AL while
simultaneously asserting either B0SEL or B1SEL.
6.
7.
The state of R/W only affects the AD<15:0> bus state
when either B0SEL or B1SEL is active. When CS is
driven low, R/W is driven low, or both B0SEL and
B1SEL are driven low, AD<15:0> stays in a
high-impedance state.
If a subsequent read or write of the same memory
address is desired, it is possible to restrobe B0SEL or
B1SEL without going through another address latch
cycle.
To perform a read operation:
1.
2.
3.
4.
5.
6.
Sample timing diagrams for reading and writing data in
this mode are provided in Figure 5-23 and Figure 5-24,
respectively.
Raise CS (if connected to the host).
Present the address to be read onto AD<13:0>.
Strobe AL high, then low.
Raise R/W.
Set the host controller’s AD<15:0> bus pins as
inputs.
Raise either B0SEL or B1SEL, or both.
FIGURE 5-22:
Raise CS (if connected to the host).
Present the address to write to on AD<13:0>.
Strobe AL.
Lower R/W.
If writing to the low byte of the memory location,
present the data on AD<7:0>, then strobe
B0SEL.
If writing to the high byte, present the data on
AD<15:8>, then strobe the B1SEL signal.
If writing a whole word, strobe both B0SEL and
B1SEL simultaneously.
DEVICE CONNECTIONS FOR PSP MODE 1
Host MCU
PMCSx
PMRD/PMWR
PMENB0
PMENB1
(2)
PMALL
ENC624J600
CS(1)
R/W
B0SEL
B1SEL(2)
AL
16
AD<15:0>
PMD<15:0>
INTx(3)
INT/SPISEL
+3.3V
100 k
Note
PSPCFG1
PSPCFG2
PSPCFG3
1:
Use of the CS strobe from the controller is optional. If not used, tie CS to VDD.
2:
B0SEL and B1SEL may optionally be tied together to form a 16-bit write strobe. See Section 5.2.3 “Write Select Pins” for
details.
3:
Use of the external interrupt signal to the controller is optional.
 2010 Microchip Technology Inc.
DS39935C-page 69
ENC424J600/624J600
FIGURE 5-23:
MODE 10 READ OPERATION TIMING (FOUR BYTES – SAME ADDRESS)
CS
T PSP12
R/W
TPSP1
B0SEL
T PSP4
B1SEL
AL
AD<15:0>
TPSP13
Hi-Z
Address<13:0>
T PSP12
FIGURE 5-24:
T PSP15
T PSP14
Data<15:0>
T PSP2
Hi-Z
Data<15:0>
Hi-Z
TPSP3
MODE 10 WRITE OPERATION TIMING (THREE BYTES – SAME ADDRESS)
CS
T PSP12
R/W
T PSP5
B0SEL
T PSP8
TPSP11
B1SEL
AL
AD<15:0>
TPSP13
Hi-Z
Address<13:0>
TPSP12
DS39935C-page 70
T PSP14
Data<15:0>
TPSP7
Data<7:0>
Hi-Z
TPSP10
 2010 Microchip Technology Inc.
ENC424J600/624J600
6.0
ETHERNET OVERVIEW
6.1.1
Before discussing the use of ENC424J600/624J600
devices in Ethernet applications, it may be helpful to
review the structure of a typical data frame. For more
detailed information, refer to IEEE 802.3 Standard, which
defines the Ethernet protocol, or to Microchip Application
Note AN1120, “Ethernet Theory of Operation”.
6.1
Frame Format
When using ENC424J600/624J600 devices, the start
of stream/preamble and Start-Of-Frame delimiter fields
are automatically generated for transmitted frames and
stripped from received ones. These bytes are not
written to the data buffer and the host controller does
not need to account for these bytes.
6.1.2
Ethernet communications utilize a series of frames to
transmit data between nodes. (These frames are also
commonly referred to as “packets”, and in the context of
this document, the two terms will be used interchangeably.) Compliant Ethernet frames are between 64 and
1518 bytes long. They consist of five or six different
fields: a destination MAC address, source MAC
address, type/length field, data payload, optional
padding field and a Cyclic Redundancy Check (CRC).
Additionally, when transmitted on the Ethernet medium,
a start of stream/preamble field and a Start-Of-Frame
(SOF) delimiter byte are appended to the beginning of
the Ethernet frame. Thus, traffic seen on the twisted-pair
cabling will appear as shown in Figure 6-1.
FIGURE 6-1:
START OF STREAM/PREAMBLE
AND START-OF-FRAME DELIMITER
DESTINATION ADDRESS
The destination address is a 6-byte field containing the
MAC address of the device to which the frame is
directed. If the Least Significant bit in the first byte of
this address is clear (i.e., the first byte of the address is
even), the address is a Unicast address. For example,
00-00-BA-BE-F0-0D and 32-45-DE-AD-BE-EF Unicast
addresses,
while
01-00-BA-BE-F0-0D
and
33-45-DE-AD-BE-EF are not. Frames with a Unicast
destination are designated for usage by the addressed
node only.
ETHERNET PACKET FORMAT
Number
of Bytes
Field
Comments
7
Start of Stream/
Preamble
Filtered Out by the Module
1
SFD
Start-Of-Frame Delimiter
(filtered out by the module)
6
DA
Destination Address,
such as Multicast, Broadcast or Unicast
6
SA
Source Address
2
Type/Length
Used in the
Calculation
of the FCS
Type of Packet or the Length of the Packet
Data
Packet Payload
(with optional padding)
46-1500
Padding
4
Note 1:
FCS(1)
Frame Check Sequence – CRC
The FCS is transmitted starting with bit 31 and ending with bit 0.
 2010 Microchip Technology Inc.
DS39935C-page 71
ENC424J600/624J600
If the Least Significant bit in the first byte of this address
is set (i.e., the byte is odd), the address is a Multicast
destination.
From
the
previous
example,
01-00-BA-BE-F0-0D and 33-45-DE-AD-BE-EF are
Multicast addresses. Multicast frames are designated
for use by a selected group of Ethernet nodes. The
Multicast address, FF-FF-FF-FF-FF-FF, is reserved; it
is known as the Broadcast address and is directed to all
nodes on the network.
ENC424J600/624J600 devices incorporate several
packet filters which can be configured to accept or discard Unicast, Multicast and/or Broadcast frames. For
details about these and other receive filters, refer to
Section 10.0 “Receive Filters”. When transmitting
frames, the host controller is responsible for writing the
desired destination address into the transmit buffer.
6.1.3
SOURCE ADDRESS
The source address is a 6-byte field containing the
MAC address of the node which transmitted the Ethernet frame. Every Ethernet device must have a globally
unique MAC address. Each ENC424J600/624J600
device has a unique address which is loaded into the
MAADR registers on power-up. This value can be used
as is, or the registers may be reconfigured with a
different address.
6.1.4
TYPE/LENGTH
The type/length field is a 2-byte field indicating the protocol to which the frame belongs. Applications using
standards such as Internet Protocol (IP) or Address
Resolution Protocol (ARP) should use the type code
specified in the appropriate standards document.
Alternately, this field can be used as a length field when
implementing proprietary networks. Typically, any
value of 1500 (05DCh) or smaller is considered to be a
length field and specifies the amount of non-padding
data which follows in the data field.
6.1.5
DATA
6.1.6
PADDING
The padding field is a variable length field appended to
meet IEEE 802.3 specification requirements when
transmitting small data payloads. As mentioned, the
minimum Ethernet frame size is 64 bytes. Removing
the 18 bytes of address and type information, and the
terminating 4-byte CRC, leaves a minimum of 46 bytes.
Smaller frames must be padded to fill this space.
When transmitting frames, ENC424J600/624J600
devices can automatically generate zero padding if the
PADCFG<2:0> bits (MACON2<7:5>) are configured to
do so. Otherwise, the application must append the
appropriate padding. The device will not prevent the
transmission of these “runt” frames if the host
commands such an action, but the frame is likely to be
dropped by other nodes.
When receiving frames, ENC424J600/624J600 devices
accept and write all padding to the receive buffer.
Frames shorter than the required 64 bytes can optionally
be filtered by the Runt Error Reject filter, described in
Section 10.4 “Runt Error Rejection Filter”.
6.1.7
CRC
The CRC is a 4-byte field containing a standard 32-bit
CRC calculated over the destination, source, type, data
and padding fields. It allows for the detection of
transmission errors.
When transmitting frames, ENC424J600/624J600
devices can automatically generate and append a valid
CRC if the PADCFG<2:0> bits are configured to do so.
Otherwise, the host controller must generate and
append this value. It is strongly recommended that the
PADCFG bits be configured so that the hardware
automatically manages this field.
When receiving frames, ENC424J600/624J600
devices accept and write the CRC field to the receive
buffer. Frames with invalid CRC values can be
discarded by the CRC Error Rejection filter, described
in Section 10.3 “CRC Error Rejection Filter”.
The data field typically consists of between 0 and
1500 bytes of payload data for each frame.
ENC424J600/624J600 devices are capable of transmitting and receiving frames larger than this when the
Huge Frame Enable bit, HFRMEN (MACON2<2>), is
set. However, these larger data frames violate Ethernet
specifications and will likely be dropped by most
Ethernet nodes.
DS39935C-page 72
 2010 Microchip Technology Inc.
ENC424J600/624J600
7.0
RESET
7.2
ENC424J600/624J600 differentiates between five
types of Resets:
•
•
•
•
•
Power-on Reset (POR)
System Reset
Transmit Only Reset
Receive Only Reset
PHY Subsystem Reset
A simplified block diagram of the on-chip Reset circuit
is shown in Figure 7-1.
7.1
Power-on Reset
Power-on Reset occurs when VDD rises above VPOR.
This allows the device to start in the initialized state
when VDD is adequate for the device’s digital logic to
operate correctly. The POR circuitry is always enabled.
To ensure proper POR operation, the application circuit
must meet the specified minimum rise rate of VDD
(SVDD, DC parameter D003).
After a Power-on Reset, the contents of the SRAM buffer
and cryptographic memories are unknown. However, all
registers will be loaded with their specified Reset values.
The PHY and other logic should still not be accessed
immediately after the POR. See Section 8.1 “Reset”
for the recommended Reset procedure.
FIGURE 7-1:
System Reset
A System Reset reverts all registers back to their
default Reset values, with the exception of
COCON<3:0> (ECON2<11:8>), which controls the
frequency output on CLKOUT. All transmit, receive,
MAC, PHY, DMA and cryptographic logic are reset.
Additionally, if the SPI interface is used, the current
internal bank selection is reset to Bank 0. The packet
buffer, cryptographic memories and the PSP address
latch used in Multiplexed Parallel modes are unaffected
by a System Reset.
To initiate a System Reset, set the ETHRST bit
(ECON2<4>). The bit is automatically cleared by
hardware. After setting ETHRST, a delay of 25 s is
required before the ENCX24J600 can be accessed
again through the SPI or PSP interfaces. Additionally,
all PHY registers and status bits derived from the PHY
should not be accessed or used for an additional period
of 256 s.
A System Reset does not cause the SPISEL and
PSPCFGx pin states to be relatched. Therefore, the currently selected controller interface remains available
after issuing a System Reset and waiting the required
25 s.
ON-CHIP RESET CIRCUIT
Reset I/O Interface
and CLKOUT
POR
System Reset
(ETHRST)
Transmit Reset
(TXRST)
Reset SFRs and
SPI Bank Select
Reset TX
Reset RX
Receive Reset
(RXRST)
Reset PHY
PHY Reset
(PRST)
 2010 Microchip Technology Inc.
DS39935C-page 73
ENC424J600/624J600
7.3
Transmit Only Reset
A Transmit Only Reset is performed by setting the
TXRST bit (ECON2<6>). The transmit logic is held in
Reset until the bit is cleared. Any pending transmission
is aborted and TXRTS (ECON1<1>) is cleared. To
resume normal operation, clear the TXRST bit.
Both the POR and System Resets automatically perform
a Transmit Reset, so this step does not need to be performed after a System or Power-on Reset. Only the
transmit logic is affected by this operation. Other register
and control blocks are not affected by this event.
7.4
Receive Only Reset
A Receive Only Reset is performed by setting the
RXRST bit (ECON2<5>). The receive logic is held in
Reset until the bit is cleared. Any packet being received
is aborted and RXEN (ECON1<0>) is cleared. To
resume normal operation, clear the RXRST bit.
7.5
PHY Subsystem Reset
The PHY module may be reset by setting the PRST bit
(PHCON1<15>). The PHY register contents all revert
to their default values.
Unlike the Transmit and Receive Only Resets, the PHY
cannot be removed from Reset immediately after setting
PRST. The PHY requires a delay, after which the
hardware automatically clears the PRST bit. It is recommended that, after issuing a Reset, the host controller
polls PRST and waits for it to be cleared by hardware
before using the PHY.
The POR and System Resets automatically perform a
PHY Reset, so this step does not need to be performed
after a System or Power-on Reset. Only the PHY is
affected by this operation. Other register and control
blocks are not affected by this event.
Both the POR and System Resets automatically perform
a Receive Reset, so this step does not need to be performed after a System or Power-on Reset. Only the
receive logic is affected by this operation. Other register
and control blocks are not affected by this event.
Following a Receive Only Reset, it is necessary to
manually reconfigure the RX SFRs for normal receive
operation again. For example, applications must clear
the PKTCNT field in ESTAT by setting the PKTDEC bit
(ECON1<8>) enough times for the count to reach zero.
Similarly, applications must reset the ERXST and
ERXTAIL Pointers before enabling reception again with
the RXEN bit.
DS39935C-page 74
 2010 Microchip Technology Inc.
ENC424J600/624J600
8.0
INITIALIZATION
Before using an ENCX24J600 device to transmit and
receive packets, certain device settings must be initialized. Depending on the application, some configuration
options may be left set to their default values. Those
that need to be changed are typically set once after
power-up and not changed thereafter.
8.1
Reset
Because it is possible for the host controller to reset
independently from the ENCX24J600 (for example,
when using an external debugger to reprogram the
host), it is recommended that software issue a System
Reset of the ENCX24J600 as the first step of its
ordinary initialization routine.
Also, since it is possible for the host controller to exit its
POR, begin code execution before the ENCX24J600
exits POR and latches the Interface mode, special care
should be taken in the software to ensure that it does
not attempt to blindly initialize the ENCX24J600
registers before the device is actually out of Reset. To
take care of these potential pitfalls, it is recommended
that firmware take a write-verify-reset-reverify
approach to ensure proper start-up. For example:
1.
2.
3.
4.
5.
6.
7.
Write 1234h to EUDAST.
Read EUDAST to see if it now equals 1234h. If
it does not, the SPI/PSP interface may not be
ready yet, so return to step 1 and try again.
Poll CLKRDY (ESTAT<12>) and wait for it to
become set.
Issue a System Reset command by setting
ETHRST (ECON2<4>).
In software, wait at least 25 s for the Reset to
take place and the SPI/PSP interface to begin
operating again.
Read EUDAST to confirm that the System Reset
took place. EUDAST should have reverted back
to its Reset default of 0000h.
Wait at least 256 s for the PHY registers and
PHY status bits to become available.
The ENCX24J600 is now ready to accept further
commands.
8.2
CLKOUT Frequency
If the ENCX24J600 is providing a system clock for the
host controller, or other hardware features of the
application, it is recommended that the application configure the output frequency on the CLKOUT pin first.
The frequency is set by using the COCON<3:0> bits
(ECON2<11:8>). By default, the output frequency on
CLKOUT after a POR is 4 MHz. The last programmed
frequency is maintained after all other Reset events.
8.3
Receive Buffer
Before packet reception is enabled, the receive buffer
must be configured by programming the ERXST
Pointer. All memory between this pointer and the end of
the physical memory (5FFFh), including those
addresses, are reserved as the receive buffer for
incoming packets. The value of ERXST must be
word-aligned, since all incoming frames must be stored
beginning at even addresses.
If an application expects a large amount of incoming
traffic or frequent packet delivery, it is recommended
that it allocate a larger receive buffer. Applications
needing more space for saving old packets or other
temporary storage, or wishing to hold several packets
ready for transmission, can allocate less memory for
the receive buffer.
Reception of incoming packets begins at the address
designated by ERXST.
8.4
Transmit Buffer
No specific transmit buffer is defined. The host applications may write frames to be transmitted to any unused
space in the SRAM buffer; no initialization is necessary.
8.5
Receive Filters
Before enabling packet reception, configure the receive
filters to eliminate unwanted incoming packets. See
Section 10.0 “Receive Filters” for details.
8.6
MAC Initialization
Once the receive buffer and filters are properly
configured, several MAC registers must be configured.
The order of programming is unimportant.
• If flow control operation is desired, configure the
flow control module as described in Section 11.0
“Flow Control”.
• Verify that the TXCRCEN (MACON2<4>) and
PADCFG<2:0> (MACON2<7:5>) bits are set
correctly. Most applications will not need to modify
these settings from their power-on defaults.
• Program the MAMXFL register with the maximum
frame length to be accepted (received or transmitted). Most network nodes are configured to
handle packets that are 1518 bytes or less
(1522 bytes or less if VLAN tagging is used).
Alternately, set HFRMEN (MACON2<2>) to
accept any size frame.
• Set the RXEN bit (ECON1<0>) to enable packet
reception by the MAC.
For more information on using the output of the
CLKOUT pin, see Section 2.2 “CLKOUT Pin”.
 2010 Microchip Technology Inc.
DS39935C-page 75
ENC424J600/624J600
8.6.1
PREPROGRAMMED MAC ADDRESS
As shipped, each ENCX24J600 device has been
preprogrammed with a unique MAC address. This
value is stored in nonvolatile memory and reloaded into
the MAADR registers after every Power-on and System
Reset. The factory preprogrammed MAC address is
permanent and will be restored to the MAC registers
after each Reset.
The preprogrammed address in nonvolatile memory
cannot be changed by the user, but it can be overwritten in the SFRs. If the user requires a different MAC
address value, the MAADR registers will need to be
written with the new MAC values by the host
application after each Reset.
8.7
PHY Initialization
Depending on the application, the PHY may need to be
configured during initialization. Typically, when using
auto-negotiation, users should write 0x05E1 to PHANA
to advertise flow control capability. Only special test
code, such as when attempting to do loopback tests,
needs other settings in the PHY to be reconfigured.
8.8
Other Considerations Following
Reset
Beyond the steps already described, there are additional configuration options that may need to be
adjusted following a device Reset. Normally, the default
configurations of these items on Power-on Reset do
not need to be changed.
For Half-Duplex mode:
• Verify that DEFER (MACON2<14>), BPEN
(MACON2<13>) and NOBKOFF (MACON2<12>)
are set correctly. These bits only apply when
operating in Half-Duplex mode; most applications
do not need to modify these settings from their
power-on defaults. For IEEE 802.3 compliance,
keep the DEFER bit set.
• Configure the Non-Back-to-Back Inter-Packet
Gap register, MAIPG (Register 8-5). Most applications program this register to 12h, which selects
maximum performance while complying with the
IEEE 802.3 IPG previously specified.
• Set the MAXRET<3:0> (MACLCON<3:0>) bits to
select the maximum number of retransmission
attempts after a collision is detected. Most
applications do not need to change this from the
default value.
8.9
After Link Establishment
Several MAC configuration parameters are dependent
upon the current duplex mode of the link. Once
auto-negotiation completes, or the speed and duplex
modes are manually reconfigured, these registers must
be updated accordingly. For details about
auto-negotiation
and
manual
speed/duplex
configuration, refer to Section 12.0 “Speed/Duplex
Configuration and Auto-Negotiation”.
Once these steps are performed, packet reception is
re-enabled by setting RXEN (ECON1<0>). The host
controller may also begin to transmit packets as
described in Section 9.1 “Transmitting Packets”.
Before transmitting the first packet after link establishment or auto-negotiation, the MAC duplex configuration
must be manually set to match the duplex configuration
of the PHY. To do this, configure FULDPX
(MACON2<0>) to match PHYDPX (ESTAT<10>).
For Half-Duplex mode, configure the Back-to-Back
Inter-Packet Gap register, MABBIPG (Register 8-4), to
set the nibble time offset delay between the end of one
transmission and the beginning of the next in a
back-to-back sequence. Program the register value as
the desired period in nibble times, minus 6. Most
applications will program this register to 12h, which
represents the minimum Inter-Packet Gap (IPG)
specified by IEEE 802.3, of 0.96 s (at 100 Mb/s) or
9.6 s (at 10 Mb/s).
For Full-Duplex mode, configure the Back-to-Back
Inter-Packet Gap register, MABBIPG, to set the nibble
time offset delay between the end of one transmission
and the beginning of the next in a back-to-back
sequence. The register value should be programmed
as the desired period in nibble times, minus 3. Most
applications will program this register to 15h, which
represents the minimum IEEE 802.3 specified
Inter-Packet Gap (IPG) of 0.96 s (at 100 Mb/s) or
9.6 s (at 10 Mb/s).
For Full-Duplex mode:
• Configure the low byte of the Non-Back-to-Back
Inter-Packet Gap register, MAIPGL. Most applications program this register to 12h, which selects
maximum performance while complying with the
IEEE 802.3 IPG previously specified.
DS39935C-page 76
 2010 Microchip Technology Inc.
ENC424J600/624J600
REGISTER 8-1:
ECON2: ETHERNET CONTROL REGISTER 2
R/W-1
R/W-1
R/W-0
R/W-0
R/W-1(1)
R/W-0(1)
R/W-1(1)
R/W-1(1)
ETHEN
STRCH
TXMAC
SHA1MD5
COCON3
COCON2
COCON1
COCON0
bit 15
bit 8
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
AUTOFC
TXRST
RXRST
ETHRST
MODLEN1
MODLEN0
AESLEN1
AESLEN0
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 15
ETHEN: Ethernet Enable bit
1 = Device is enabled (normal operation)
0 = Device is disabled (reduced power)
bit 14
STRCH: LED Stretching Enable bit
1 = Stretch transmit, receive and collision events on LEDA and LEDB to 50 ms
0 = LEDA and LEDB outputs show real-time status without stretching
bit 13
TXMAC: Automatically Transmit MAC Address Enable bit
1 = MAADR1-MAADR6 registers are automatically inserted into the source address field of all
transmitted packets
0 = No automatic source address insertion
bit 12
SHA1MD5: SHA-1/MD5 Hash Control bit
1 = Hashing engine computes a SHA-1 hash
0 = Hashing engine computes an MD5 hash
bit 11-8
COCON<3:0>: CLKOUT Frequency Control bits(1)
1111 = 50 kHz nominal ((4 * FOSC)/2000)
1110 = 100 kHz nominal ((4 * FOSC)/1000)
1101 = No output (DC sinking to VSS)
1100 = 3.125 MHz nominal ((4 * FOSC)/32)
1011 = 4.000 MHz nominal ((4 * FOSC)/25)
1010 = 5.000 MHz nominal ((4 * FOSC)/20)
1001 = 6.250 MHz nominal ((4 * FOSC)/16)
1000 = 8.000 MHz nominal ((4 * FOSC)/12.5); duty cycle is not 50%
0111 = 8.333 MHz nominal ((4 * FOSC)/12)
0110 = 10.00 MHz nominal ((4 * FOSC)/10)
0101 = 12.50 MHz nominal ((4 * FOSC)/8)
0100 = 16.67 MHz nominal ((4 * FOSC)/6)
0011 = 20.00 MHz nominal ((4 * FOSC)/5)
0010 = 25.00 MHz nominal ((4 * FOSC)/4)
0001 = 33.33 MHz nominal ((4 * FOSC)/3)
0000 = No output (DC sinking to VSS)
bit 7
AUTOFC: Automatic Flow Control Enable bit
1 = Automatic flow control is enabled
0 = Automatic flow control is disabled
bit 6
TXRST: Transmit Logic Reset bit
1 = Transmit logic is held in Reset. TXRTS (ECON1<1>) is automatically cleared by hardware when
this bit is set.
0 = Transmit logic is not in Reset (normal operation)
Note 1:
Reset value on POR events only. All other Resets leave these bits unchanged.
 2010 Microchip Technology Inc.
DS39935C-page 77
ENC424J600/624J600
REGISTER 8-1:
ECON2: ETHERNET CONTROL REGISTER 2 (CONTINUED)
bit 6
RXRST: Receive Logic Reset bit
1 = Receive logic is held in Reset. RXEN (ECON1<0>) is automatically cleared by hardware when this
bit is set.
0 = Receive logic is not in Reset (normal operation)
bit 4
ETHRST: Master Ethernet Reset bit
1 = All TX, RX, MAC, PHY, DMA, modular exponentiation, hashing and AES logic, and registers
(excluding COCON) are reset. Hardware self-clears this bit to ‘0’. After setting this bit, wait at least
25 s before attempting to read or write to the ENCX24J600 via the SPI or PSP interface.
0 = Device is not in Reset (normal operation)
bit 3-2
MODLEN<1:0>: Modular Exponentiation Length Control bits
11 = Reserved
10 = 1024-bit modulus and operands
01 = 768-bit modulus and operands
00 = 512-bit modulus and operands
bit 1-0
AESLEN<1:0>: AES Key Length Control bits
11 = Reserved
10 = 256-bit key
01 = 192-bit key
00 = 128-bit key
Note 1:
Reset value on POR events only. All other Resets leave these bits unchanged.
DS39935C-page 78
 2010 Microchip Technology Inc.
ENC424J600/624J600
REGISTER 8-2:
EIDLED: ETHERNET ID STATUS/LED CONTROL REGISTER
R/W-0
R/W-0
R/W-1
R/W-0
R/W-0
R/W-1
R/W-1
R/W-0
LACFG3
LACFG2
LACFG1
LACFG0
LBCFG3
LBCFG2
LBCFG1
LBCFG0
bit 15
bit 8
R-0
R-0
R-1
R
R
R
R
R
DEVID2
DEVID1
DEVID0
REVID4
REVID3
REVID2
REVID1
REVID0
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 15-12,
bit 11-8
LACFG<3:0>: LEDA Configuration bits and
LBCFG<3:0: LEDB Configuration bits
1111 = Display link and speed state, transmit and receive events(1)
1110 = Display link and duplex state, transmit and receive events(1)
1101 = Reserved
1100 = Display link state, collision events; pin is driven high when a link is present and driven low
temporarily when a collision occurs
1011 = Display link state, transmit and receive events; pin is driven high when a link is present and
driven low while a packet is being received or transmitted
1010 = Display link state, receive events; pin is driven high when a link is present and driven low while
a packet is being received
1001 = Display link state, transmit events; pin is driven high when a link is present and driven low while
a packet is being transmitted
1000 = Display speed state; pin is driven high when in 100 Mbps mode and a link is present
0111 = Display duplex state; pin is driven high when the PHY is in full duplex (PHYDPX (ESTAT<10>)
is ‘1’) and a link is present
0110 = Display transmit and receive events; pin is driven high while a packet is either being received
or transmitted
0101 = Display receive events; pin is driven high while a packet is being received
0100 = Display transmit events; pin is driven high while a packet is being transmitted
0011 = Display collision events; pin is temporarily driven high when a collision occurs
0010 = Display link state; pin is driven high when linked
0001 = On (pin is driven high)
0000 = Off (pin is driven low)
bit 7-5
DEVID<2:0>: Device ID bits
001 = ENC624J600 family device
bit 4-0
REVID<4:0>: Silicon Revision ID bits
Indicates current silicon revision.
Note 1:
These configurations require that a bi-color LED be connected between the LEDA and LEDB pins, and
that LACFG<3:0> and LBCFG<3:0> be set to the same value. See Section 2.5.1 “Using Bi-Color
LEDs” for detailed information.
 2010 Microchip Technology Inc.
DS39935C-page 79
ENC424J600/624J600
REGISTER 8-3:
MACON2: MAC CONTROL REGISTER 2
U-0
R/W-1
R/W-0
R/W-0
U-0
U-0
R/W-0
R/W-0
—
DEFER
BPEN
NOBKOFF
—
—
r
r
bit 15
bit 8
R/W-1
PADCFG2
R/W-0
PADCFG1
R/W-1
PADCFG0
R/W-1
TXCRCEN
R/W-0
PHDREN
R/W-0
R/W-1
R/W-0
HFRMEN
r
FULDPX
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 15
Unimplemented: Read as ‘0’
bit 14
DEFER: Defer Transmission Enable bit (applies to half duplex only)
1 = When the medium is occupied, the MAC will wait indefinitely for it to become free when attempting
to transmit (use this setting for IEEE 802.3 compliance)
0 = When the medium is occupied, the MAC will abort the transmission after the excessive deferral
limit is reached (24,288 bit times)
bit 13
BPEN: No Backoff During Back Pressure Enable bit (applies to half duplex only)
1 = After incidentally causing a collision during back pressure, the MAC immediately begins retransmitting
0 = After incidentally causing a collision during backpressure, the MAC delays using the binary
exponential backoff algorithm before attempting to retransmit (normal operation)
bit 12
NOBKOFF: No Backoff Enable bit (applies to half duplex only)
1 = After any collision, the MAC immediately begins retransmitting
0 = After any collision, the MAC delays using the binary exponential backoff algorithm before
attempting to retransmit (normal operation)
bit 11-10
Unimplemented: Read as ‘0’
bit 9-8
Reserved: Write as ‘0’
bit 7-5
PADCFG<2:0>: Automatic Pad and CRC Configuration bits
111 = All short frames are zero-padded to 64 bytes and a valid CRC is then appended
110 = No automatic padding of short frames
101 = MAC automatically detects VLAN protocol frames which have a 8100h type field and automatically pad to 64 bytes. If the frame is not a VLAN frame, it will be padded to 60 bytes. After
padding, a valid CRC is appended.
100 = No automatic padding of short frames
011 = All short frames are zero-padded to 64 bytes and a valid CRC is then appended
010 = No automatic padding of short frames
001 = All short frames will be zero-padded to 60 bytes and a valid CRC is then appended
000 = No automatic padding of short frames
bit 4
TXCRCEN: Transmit CRC Enable bit
1 = MAC appends a valid CRC to all frames transmitted regardless of the PADCFG bits. TXCRCEN
must be set if the PADCFG bits specify that a valid CRC will be appended.
0 = MAC does not append a CRC. The last 4 bytes are checked and if it is an invalid CRC, it is to be
reported by setting CRCBAD (ETXSTAT<4>).
bit 3
PHDREN: Proprietary Header Enable bit
1 = Frames presented to the MAC contain a 4-byte proprietary header which is not used when
calculating the CRC
0 = No proprietary header is present; the CRC covers all data (normal operation)
DS39935C-page 80
 2010 Microchip Technology Inc.
ENC424J600/624J600
REGISTER 8-3:
MACON2: MAC CONTROL REGISTER 2 (CONTINUED)
bit 2
HFRMEN: Huge Frame Enable bit
1 = Frames of any size will be allowed to be transmitted and received
0 = Frames bigger than MAMXFL will be aborted when transmitted or received
bit 1
Reserved: Write as ‘1’
bit 0
FULDPX: MAC Full-Duplex Enable bit
1 = MAC operates in Full-Duplex mode. For proper operation, the PHY must also be set to Full-Duplex
mode.
0 = MAC operates in Half-Duplex mode. For proper operation, the PHY must also be set to Half-Duplex
mode.
REGISTER 8-4:
MABBIPG: MAC BACK-TO-BACK INTER-PACKET GAP REGISTER
U-0
U-0
U-0
U-0
U-0
U-0
U-0
U-0
—
—
—
—
—
—
—
—
bit 15
bit 8
U-0
R/W-0
R/W-0
R/W-1
R/W-0
R/W-0
R/W-1
R/W-0
—
BBIPG6
BBIPG5
BBIPG4
BBIPG3
BBIPG2
BBIPG1
BBIPG0
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 15-7
Unimplemented: Read as ‘0’
bit 6-0
BBIPG<6:0>: Back-to-Back Inter-Packet Gap Delay Time Control bits
When FULDPX (MACON2<0>) = 1:
Nibble time offset delay between the end of one transmission and the beginning of the next in a
back-to-back sequence. The register value should be programmed to the desired period in nibble times
minus 3. The recommended setting is 15h which represents the minimum IEEE specified Inter-Packet
Gap (IPG) of 0.96 s (at 100 Mb/s) or 9.6 s (at 10 Mb/s).
When FULDPX (MACON2<0>) = 0:
Nibble time offset delay between the end of one transmission and the beginning of the next in a
back-to-back sequence. The register value should be programmed to the desired period in nibble times
minus 6. The recommended setting is 12h which represents the minimum IEEE specified Inter-Packet
Gap (IPG) of 0.96 s (at 100 Mb/s) or 9.6 s (at 10 Mb/s).
 2010 Microchip Technology Inc.
DS39935C-page 81
ENC424J600/624J600
REGISTER 8-5:
MAIPG: MAC INTER-PACKET GAP REGISTER
U-0
R/W-0
R/W-0
R/W-0
R/W-1
R/W-1
R/W-0
R/W-0
—
r
r
r
r
r
r
r
bit 15
bit 8
U-0
R/W-0
R/W-0
R/W-1
R/W-0
R/W-0
R/W-1
R/W-0
—
IPG6
IPG5
IPG4
IPG3
IPG2
IPG1
IPG0
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 15
Unimplemented: Read as ‘0’
bit 14-8
Reserved: Write as ‘0001100’ (0Ch)
bit 7
Unimplemented: Read as ‘0’
bit 6-0
IPG<6:0>: Non Back-to-Back Inter-Packet Gap Delay Time Control bits
Inter-Packet Gap (IPG) between the end of one packet received or transmitted and the start of the next
packet transmitted. For maximum performance while meeting IEEE 802.3 compliance, leave this field
set to 12h, which represents an Inter-Packet Gap time of 0.96 s (at 100 Mb/s) or 9.6 s (at 10 Mb/s).
REGISTER 8-6:
MACLCON: MAC COLISION CONTROL REGISTER
U-0
U-0
R/W-1
R/W-1
R/W-0
R/W-1
R/W-1
R/W-1
—
—
r
r
r
r
r
r
bit 15
bit 8
U-0
U-0
U-0
U-0
R/W-1
R/W-1
R/W-1
R/W-1
—
—
—
—
MAXRET3
MAXRET2
MAXRET1
MAXRET0
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 15-14
Unimplemented: Read as ‘0’
bit 13-8
Reserved: Write as ‘110111’ (37h)
bit 7-4
Unimplemented: Read as ‘0’
bit 3-0
MAXRET<3:0>: Maximum Retransmissions Control bits (half duplex only)
Maximum retransmission attempts the MAC will make before aborting a packet due to excessive
collisions.
DS39935C-page 82
 2010 Microchip Technology Inc.
ENC424J600/624J600
9.0
TRANSMITTING AND
RECEIVING PACKETS
Beyond providing the transceiver interface to the
network medium, ENC424J600/624J600 devices also
handle many of the mechanical tasks of packet
management, off-loading much of the routine Ethernet
housekeeping from the host application. The device
manages the separate transmit and receive buffers,
handles transmission and potential collisions, filters
incoming packets, and stores received packets with the
additional information required for processing. The
host controller writes data to the memory, configures
the length of the packet to send, initiates the transmissions and reads incoming packets from the receive
buffer. Padding and checksum generation, as well as
status information on received packets, are all handled
automatically.
FIGURE 9-1:
EXAMPLES OF TX
BUFFER WRAPPING
0000h
Packet 2
(cont.)
0100h
4200h
General
Purpose
Buffer
Packet 1
4600h
Packet 2
9.1
Transmitting Packets
The general purpose buffer is bounded by the beginning of the address space (0000h) and the last byte
before the beginning of the receive buffer (ERXST – 1).
Since ERXST must be word-aligned, both buffers start
on even addresses and end on odd addresses. For
details on buffer allocation, see Section 3.5 “SRAM
Buffer”.
The packet to be transmitted is defined by two values:
the Transmit Data Start Pointer, ETXST, and the
Transmit Buffer Length Pointer, ETXLEN. When transmitting a packet, the device reads the ETXLEN bytes,
beginning at the address indicated by ETXST. If the end
of the general purpose buffer is encountered during this
process, the operation will wrap around to the beginning
of the general purpose buffer space (0000h). Packets
can also be transmitted directly from the receive buffer
(for instance, when changing the source and destination
addresses). If the end of the receive buffer is
encountered, the operation wraps to the beginning of the
receive buffer instead. This wrap-around behavior
precludes packets from spanning both buffers.
Figure 9-1 shows three examples of the wrapping
behavior. Packet 1 in the diagram is transmitted without
any wrapping. Packet 2 reaches the end of the general
purpose buffer, and therefore, wraps to address 0000h.
Packet 3 is being transmitted from the receive buffer,
and therefore, wraps to ERXST when the end of the
receive buffer is reached.
The device can be configured to insert the source MAC
address using the values from the MAADR registers.
This feature is enabled by setting the TXMAC bit
(ECON2<13>). When enabled, the device reads the
6-byte destination address from memory, inserts the
6-byte source MAC address from the MAADR registers
into the transmitted byte stream, then continues reading
and transmitting the remaining bytes from memory.
 2010 Microchip Technology Inc.
ERXST
4800h
Packet 3
(cont.)
4900h
Receive
Buffer
5F00h
Packet 3
5FFFh
Example
Packet
ETXST
ETXLEN
1
4200h
1024
2
4600h
768
3
5F00h
512
The value of ETXLEN only indicates the number of
bytes to read from memory, not the number of bytes to
be transmitted. If the device is configured to insert the
source MAC address, add padding or append the CRC;
the actual number of bytes transmitted on the physical
medium will increase. Figure 9-2 shows how to
configure ETXLEN for three identical packets of data
when various transmission options are configured.
Before transmitting any packets, the device needs to
be initialized (see Section 8.0 “Initialization”). Setting
TXRTS (ECON1<1>) initiates the transmission. This bit
is automatically cleared by hardware when the operation is complete. In addition, the device can also be
configured to assert the TXIF interrupt and the external
interrupt signal on completion (see Section 13.0
“Interrupts” for additional details).
Transmission operations can be aborted by manually
clearing the TXRTS bit at any time. If a packet transmission is in progress, it will be aborted immediately and the
device will send a jam signal, effectively notifying the link
partner to discard any partial packet it has received.
DS39935C-page 83
ENC424J600/624J600
FIGURE 9-2:
EXAMPLES FOR SELECTING ETXLEN VALUES
Example 1: Source Address and Padding Provided by Application
0120h
0130h
Destination
Address
Source
Address
Protocol
015Bh
0156h
00 1F 2E 3D 4C 5B 00 04 A3 11 22 33 80 00 00 01 02
28 00 00 00 00 00 00 1F 2E 3D
...
Data
Padding
...
Next Packet
MAC address insertion disabled (TXMAC = 0)
Automatic padding disabled (PADCFG<2:0> = 000)
CRC generation enabled (TXCRCEN = 1)
ETXST = 0120h
ETXLEN = 3Ch
Example 2: Padding Provided by Application, Source Address to be Inserted by ENCX24J600
0120h
012Ah
00 1F 2E 3D 4C 5B 80 00 00 01 02
Destination
Address
Protocol
0150h
...
0155h
28 00 00 00 00 00 00 1F 2E 3D
Data
Padding
...
Next Packet
MAC address insertion enabled (TXMAC = 1)
Automatic padding disabled (PADCFG<2:0> = 000)
CRC generation enabled (TXCRCEN = 1)
ETXST = 0120h
ETXLEN = 36h
Example 3: Source Address and Padding to be Inserted by ENCX24J600
0120h
012Ah
00 1F 2E 3D 4C 5B 80 00 00 01 02
Destination
Address
ETXST = 0120h
ETXLEN = 31h
DS39935C-page 84
Protocol
Data
0150h
...
28 00 1F 2E 3D
...
Next Packet
MAC insertion enabled (TXMAC = 1)
Automatic padding enabled (PADCFG<2:0> = 101)
CRC generation enabled (TXCRCEN = 1)
 2010 Microchip Technology Inc.
ENC424J600/624J600
While transmission is active (TXRTS is set), it is recommended that ETXST and ETXLEN, as well as the
TXMAC bit (ECON2<13>), not be modified. Since
ERXST controls the end of the transmit buffer, and
therefore, buffer wrap-around, it must also remain
unchanged.
To transmit a packet:
1.
2.
3.
4.
5.
6.
7.
8.
Initialize the MAC as described in Section 8.6
“MAC Initialization”. Most applications should
leave PADCFG<3:0> and TXCRCEN set to their
default values, which enables automatic padding
and CRC generation. For automatic insertion of
the source MAC address during transmission, set
the TXMAC bit to ‘1’.
If desired, enable the transmit done and/or
transmit abort interrupts by setting TXIE and/or
TXABTIE (EIE<3:2>). Clear TXIF and TXABTIF
(EIR<3:2>) if they are currently set. To generate
the interrupt, also set INTIE (EIE<15>).
Copy the packet to the SRAM buffer.
Program ETXST to the start address of the
packet.
Program ETXLEN with the length of data copied
to the memory.
Set the TXRTS bit to initiate transmission.
Wait for the hardware to clear TXRTS and trigger
a transmit interrupt, indicating transmission has
completed.
Read the ETXSTAT register for status information
as described in the next section.
The transmit function does not modify the ETXST
Pointer or ETXLEN data length after the operation
completes. To send another packet, the Start Pointer
must be manually moved to the location of the next
packet and the transmit length must be updated. If
desired, the application can retransmit the last packet
by setting TXRTS again without modifying ETXST or
ETXLEN.
9.1.1
TRANSMISSION STATUS
After transmitting a packet (either successfully or
unsuccessfully), the ETXSTAT and ETXWIRE registers
contain status information about the operation. The
values in these registers will persist until the next
packet is transmitted (again, either successfully or
unsuccessfully). Therefore, ETXSTAT and ETXWIRE
should be treated as valid only when TXRTS is clear.
The
LATECOL
(ETXSTAT<10>),
MAXCOL
(ETXSTAT<9>) and EXDEFER (ETXSTAT<8>) bits are
error flags indicating that packet transmission has
failed. (These errors are possible only in Half-Duplex
mode; therefore, these status bits should be ignored
when operating in Full-Duplex mode.) The device
asserts these flags and clears the TXRTS bit to prevent
a single packet from stalling device operation. When
 2010 Microchip Technology Inc.
any of these flags are set, the packet was not successfully transmitted and the host controller should
determine whether to retry or ignore the error.
The CRCBAD (EXTSTAT<4>) bit is a warning. It is only
meaningful when automatic CRC generation is disabled and indicates that the checksum computed by
the MAC did not match the one appended by software.
If the software CRC is incorrect, the packet will be
rejected by the remote node. When automatic MAC
hardware generation of the CRC is enabled, this bit can
be ignored as the CRC is always correct.
The DEFER bit (ETXSTAT<7>) and the COLCNT<3:0>
bits (ETXSTAT<3:0>) are status indicators. DEFER
simply indicates that the device had to wait before
transmitting due to flow control or other traffic on the
network. The COLCNT bits indicate the number of
collisions that occurred before the packet was
successfully transmitted.
The ETXWIRE register is a count of the number of
actual bytes the MAC transmitted onto the physical
medium before the transmission completed, either
successfully or unsuccessfully. In Full-Duplex mode,
this count is the total length of the packet, including
padding and CRC. In Half-Duplex mode, this status
register includes all extra bytes that were transmitted
due to any collisions that occurred. Therefore, it can be
used to gauge how much total bandwidth the
application is using.
9.1.2
SPECIAL CASE TRANSMISSION
When the value of ETXLEN is 07h or less, the ability to
set the TXRTS bit is locked out in hardware. This is
because the resulting packet would be unable to meet
IEEE 802.3 requirements.
If the PHY is unlinked at the time software sets the
TXRTS bit to transmit a packet, the transmission will
complete normally with applicable interrupts still occurring. However, the PHY submodule will also suppress
the transmission of any data onto the physical medium.
This avoids interference with auto-negotiation, which
may be already using the physical medium. This
behavior is also necessary to meet IEEE 802.3
specifications.
If an attempt is made to transmit a packet that is larger
than specified in the MAC Maximum Frame Length register, and huge frames are disabled (MACON2<2> = 0),
the transmission will start normally. However, once the
MAC has transmitted the number of bytes defined in
MAMXFL, the MAC will immediately cease transmission. This results in the packet being partially transmitted
and then truncated without a valid CRC being
appended. In almost all cases, this results in the remote
node rejecting the packet as having an invalid CRC.
DS39935C-page 85
ENC424J600/624J600
In full duplex, the MAC inhibits transmission of any
packets until the pause timer expires when two
conditions are met:
• Flow control is enabled (RXPAUS bit is set) and
• A valid pause frame was received from the
remote node
It will still be possible for software to set the TXRTS bit
to start a transmission. However, this has the effect of
queuing the packet for future transmission instead of
causing an immediate transmission to start. Once the
pause timer expires, the queued packet will transmit
normally, causing any applicable interrupts to occur.
9.2
Receiving Packets
As Ethernet frames arrive, they are written to the circular receive buffer, bounded by the Receive Buffer Start
Address (ERXST) register and the end of the physical
memory at 5FFFh. The hardware also maintains a
counter indicating the number of pending frames.
FIGURE 9-3:
Each frame starts on an even address. The hardware
maintains a Receive Head Pointer, ERXHEAD, indicating
the next location to be written, and automatically wraps
back to ERXST when it reaches the end of memory. The
Tail Pointer, ERXTAIL, is maintained by software.
Addresses from the Tail Pointer, up to the Head Pointer,
are considered to be protected by software. This allows
the host controller to prevent incoming frames from
overwriting data that has not yet been processed.
When ERXTAIL points to the same location as
ERXHEAD, the receive packet buffer is considered to
be full. Due to this definition, there is no empty condition. For simplicity, applications may choose to keep
the Tail Pointer always set to two bytes behind the next
frame to be processed, or two bytes behind the Head
Pointer when no frames are pending. Figure 9-3 shows
these pointer relationships.
If ERXHEAD reaches ERXTAIL while receiving a
frame, or if the receive filters reject the packet, the
ERXHEAD Pointer is rolled back to its previous location
and the packet is discarded.
EXAMPLES OF RECEIVE BUFFER WRAP BETWEEN ERXHEAD AND ERXTAIL
ERXST
Initial state, buffer is empty:
5FFFh
H
T XX
...
Buffer is empty:
T XX H
...
Buffer contains pending
data to be processed:
T XX 01 02 03 04 05
...
Buffer has wrapped and
contains pending data:
05 06 07 08 0A H
Buffer has wrapped
and is currently full:
92 93 94 95 96 97 98 99 H
T XX 01 02
8A 8B 8C H
...
T XX 01 02 03 04
...
8A 8B 8C 8D 8E 8F 90 91
H
Head Pointer (ERXHEAD)
Free byte for incoming data
T
Tail Pointer (ERXTAIL), skip when reading
Byte protected from incoming data
01 02
Next Packet Pointer for pending frame
DS39935C-page 86
XX
Dummy byte, skip when reading
 2010 Microchip Technology Inc.
ENC424J600/624J600
It is possible for the host application to write to the
receive buffer. However, it is recommended not to do
so outside of the area protected by the Tail Pointer in
order to prevent it from being subsequently overwritten
by future receive packets.
ERXHEAD is a read-only register and may be updated
at any time by hardware. The high byte is shadowed to
ensure it can be safely read on 8-bit interfaces (SPI or
PSP). When reading ERXHEAD, read the low byte first.
This operation simultaneously copies the high byte to a
shadow register. Reading the high byte automatically
reads from this shadow register. This ensures that the
value has not been modified since the low byte was
obtained, even if another packet has been received in
the interim.
9.2.1
CONFIGURING PACKET
RECEPTION
Once the MAC and PHY are properly initialized, the
device is ready to begin receiving packets.
To enable reception:
1.
2.
3.
4.
5.
Program the ERXST Pointer (low byte first if
writing a byte at a time) to the first address to be
used for the receive buffer. This pointer must
indicate an even address. The Head Pointer,
ERXHEAD, will automatically be set to the same
value.
In the host controller application, create a
variable, NextPacketPointer, to hold the
address value of the next received packet.
Initialize this variable to be equal to the current
value of ERXST.
Program the Tail Pointer, ERXTAIL, to the last
even address of the buffer or 5FFEh.
Configure interrupts as desired. See
Section 13.0 “Interrupts” for more information.
Set RXEN (ECON1<0>) to enable reception.
Once RXEN is set, it is recommended that ERXST not
be modified. The host controller must monitor the
ENCX24J600 to determine when a packet has arrived
and is ready to be processed. This is accomplished by
using the packet pending interrupt as described in
Section 13.1.5 “Received
Packet
Pending”.
Alternatively, poll the PKTCNT bits for a non-zero
value.
9.2.2
Packets are stored sequentially in the receive buffer.
Each frame is stored as it was presented to the MAC,
including all padding and frame check (CRC) bytes, but
excluding any preamble or start of stream/frame delimiter bytes. Frames are always saved starting on an
even address, so those with an odd length skip one
byte before the next frame begins. A sample packet
stored in memory is shown in Figure 9-4.
When a packet is received, the hardware increments
the Packet Counter bits, PKTCNT (ESTAT<7:0>).
Incoming bytes are written sequentially, beginning at
the Head Pointer, ERXHEAD. If the Head Pointer
reaches the Tail Pointer, ERXTAIL, during reception, or
if incrementing the PKTCNT bits would cause an overflow, the packet will be discarded and the Head Pointer
restored.
Each received frame is preceded in memory by a
pointer to the next frame and a Receive Status Vector
(RSV). The RSV includes the length of the frame, and
flags indicating the type of packet and which filters
were matched. This format of the RSV is shown in
Table 9-1.
To retrieve a packet from the buffer:
1.
2.
3.
4.
5.
6.
7.
 2010 Microchip Technology Inc.
STORAGE OF INCOMING PACKETS
Verify that a packet is waiting by ensuring that
the PKTCNT<7:0> bits are non-zero or that
PKTIF (EIR<6>) is set.
Begin reading at address pointed to by the
application variable, NextPacketPointer
(see Section 9.2.1 “Configuring Packet
Reception”).
Read the first two bytes of the packet, which are
the address of the next packet and write to
NextPacketPointer.
Read the next six bytes, which are the Receive
Status Vector (RSV).
Read the Ethernet frame. The number of bytes
to be read is indicated by the received byte
count in the RSV read during step 4.
As the frame is read and processed, incremental
amounts of memory buffer can be freed up by
updating the ERXTAIL Pointer value to the point
where the packet has been processed, taking
care to wrap back at the end of the received
memory buffer. Once the whole frame has been
processed, the final value of ERXTAIL should be
equal to (NextPacketPointer – 2).
Set PKTDEC (ECON1<8>) to decrement the
PKTCNT bits. PKTDEC is automatically cleared
by hardware if PKTCNT decrements to zero.
DS39935C-page 87
ENC424J600/624J600
FIGURE 9-4:
EXAMPLE OF A RECEIVED PACKET IN BUFFER MEMORY
Memory
Previous
Packet
Current
Packet
Next
Packet
Byte Address
High
Low
Byte Address
:
:
:
:
:
:
:
011Dh
FCS[2]
FCS[3]
011Ch
011Fh
FCS[0]
FCS[1]
011Eh
ERXTAIL
0121h
01h
68h
0120h
Pointer to Next Packet
0123h
RSV[1]
RSV[0]
0122h
0125h
RSV[3]
RSV[2]
0124h
0127h
RSV[5]
RSV[4]
0126h
0129h
04h
00h
0128h
012Bh
00h
A3h
012Ah
012Dh
02h
01h
012Ch
012Fh
34h
12h
012Eh
0131h
78h
56h
0130h
0133h
BCh
9Ah
0132h
0135h
00h
80h
0134h
0137h
data[1]
data[0]
0136h
:
:
:
:
:
:
:
015Fh
PAD
data[40]
:
015Eh
0161h
PAD
PAD
0160h
0163h
PAD
PAD
0162h
0165h
FCS[2]
FCS[3]
0164h
0167h
FCS[0]
FCS[1]
0166h
0169h
XX
XX
0168h
016Bh
RSV[1]
RSV[0]
016Ah
016Dh
RSV[3]
RSV[2]
016Ch
016Fh
RSV[5]
RSV[4]
016Eh
:
:
:
:
:
:
:
DS39935C-page 88
:
Receive
Status
Vector
Destination
Address
Source
Address
Start of Next Packet
:
 2010 Microchip Technology Inc.
ENC424J600/624J600
TABLE 9-1:
Byte
5
4
3
2
1
RECEIVE STATUS VECTOR
Bit(s)
Field
47:40 Zeros
39
Zero
38
Reserved
37
Reserved
Description
00h
‘0’
36
Unicast Filter Match
Current frame met criteria for the Unicast Receive filter.
35
Pattern Match Filter Match
Current frame met criteria for the Pattern Match Receive filter as
configured when the packet was received.
34
Magic Packet™ Filter Match
Current frame met criteria for the Magic Packet Receive filter as
configured when the packet was received.
33
Hash Filter Match
Current frame met criteria for the Hash Receive filter as
configured when the packet was received.
32
Not-Me Filter Match
Current frame met criteria for the Not-Me Receive filter.
31
Runt Filter Match
Current frame met criteria for the Runt Packet Receive filter.
30
Receive VLAN Type Detected
Current frame was recognized as a VLAN tagged frame.
29
Receive Unknown Opcode
Current frame was recognized as a control frame but it contained
an unknown opcode.
28
Receive Pause Control Frame
Current frame was recognized as a control frame containing a
valid pause frame opcode and a valid destination address.
27
Receive Control Frame
Current frame was recognized as a control frame for having a
valid type/length designating it as a control frame.
26
Dribble Nibble
Indicates that after the end of this packet, an additional 1 to 7 bits
were received. The extra bits were thrown away.
25
Receive Broadcast Packet
Current frame has a valid Broadcast address.
24
Receive Multicast Packet
Current frame has a valid Multicast address.
23
Received Ok
Received packet had a valid CRC and no symbol errors.
22
Length Out of Range
Frame type/length field was larger than 1500 bytes (type field).
21
Length Check Error
Frame length field value in the packet does not match the actual
data byte length and specifies a valid length.
20
CRC Error
Frame CRC field value does not match the CRC calculated by the
MAC.
19
Reserved
18
Carrier Event Previously Seen
17
Reserved
16
Packet Previously Ignored
A frame larger than 50,000 bit times occurred or a packet has
been dropped since the last receive.
Received Byte Count
Length of the received frame in bytes. This includes the
destination address, source address, type/length, data, padding
and CRC fields. This field is stored in little-endian format.
15:0
0
 2010 Microchip Technology Inc.
A carrier event was detected at some time since the last receive.
The carrier event is not associated with this packet. A carrier event
is activity on the receive channel that does not result in a packet
receive attempt being made.
DS39935C-page 89
ENC424J600/624J600
REGISTER 9-1:
ECON1: ETHERNET CONTROL REGISTER 1
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
MODEXST
HASHEN
HASHOP
HASHLST
AESST
AESOP1
AESOP0
PKTDEC
bit 15
bit 8
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
FCOP1
FCOP0
DMAST
DMACPY
DMACSSD
DMANOCS
TXRTS
RXEN
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 15
MODEXST: Modular Exponentiation Start bit
1 = Modular exponentiation calculation started/busy; automatically cleared by hardware when done
0 = Modular exponentiation calculation done/Idle
bit 14
HASHEN: MD5/SHA-1 Hash Enable bit
1 = MD5/SHA-1 hashing engine enabled. Data written to the hashing engine by the DMA is added to
the hash.
0 = MD5/SHA-1 hashing engine disabled
bit 13
HASHOP: MD5/SHA-1 Hash Operation Control bit
1 = MD5/SHA-1 hash engine loads the Initial Value (IV) from the hash memory. This mode is typically
used for HMAC hash operations.
0 = Normal MD5/SHA-1 hash operation
bit 12
HASHLST: MD5/SHA-1 Hash Last Block Control bit
1 = The next DMA transfer to the hash engine completes the hash. If needed, padding is automatically
generated and added to the hash.
0 = The next DMA transfer to the hash engine adds data to the hash. Further data additions to the hash
are still possible.
bit 11
AESST: AES Encrypt/Decrypt Start bit
1 = AES encrypt/decrypt operation is started/busy; automatically cleared by hardware when done
0 = AES encrypt/decrypt operation is done/Idle
bit 10-9
AESOP<1:0>: AES Operation Control bits
11 = Reserved
10 = ECB/CBC decrypt
01 = CBC/CFB encrypt
00 = ECB/CFB/OFB encrypt or key initialization
bit 8
PKTDEC: RX Packet Counter Decrement Control bit
1 = Decrement PKTCNT (ESTAT<7:0>) bits by one. Hardware immediately clears PKTDEC to ‘0’,
allowing back-to-back decrement operations.
0 = Leave PKTCNT bits unchanged
bit 7-6
FCOP<1:0>: Flow Control Operation Control/Status bits
When FULDPX (MACON2<0>) = 1:
11 = End flow control by sending a pause frame with 0000h pause timer value; automatically cleared
by hardware when done
10 = Enable flow control by periodically sending pause frames with a pause timer defined by EPAUS
01 = Transmit single pause frame defined by EPAUS; automatically cleared by hardware when done
00 = Flow control disabled/Idle
When FULDPX (MACON2<0>) = 0:
1x, 01 = Enable flow control by continuously asserting backpressure (transmitting preamble)
00
= Flow control disabled/Idle
DS39935C-page 90
 2010 Microchip Technology Inc.
ENC424J600/624J600
REGISTER 9-1:
ECON1: ETHERNET CONTROL REGISTER 1 (CONTINUED)
bit 5
DMAST: DMA Start bit
1 = DMA is started/busy; automatically cleared by hardware when done
0 = DMA is done/Idle
bit 4
DMACPY: DMA Copy Control bit
1 = DMA copies data to memory location at EDMADST
0 = DMA does not copy data; EDMADST is ignored
bit 3
DMACSSD: DMA Checksum Seed Control bit
1 = DMA checksum operations are initially seeded by the one’s complement of the checksum
contained in EDMACS
0 = DMA checksum operations are initially seeded by 0000h
bit 2
DMANOCS: DMA No Checksum Control bit
1 = DMA does not compute checksums; EDMACS remains unchanged
0 = DMA computes checksums; hardware updates EDMACS at the completion of all DMA operations
bit 1
TXRTS: Transmit Request to Send Status/Control bit
1 = Transmit an Ethernet frame; automatically cleared by hardware when done
0 = Transmit logic done/Idle
bit 0
RXEN: Receive Enable bit
1 = Packets which pass the current RX filter configuration are written to the receive buffer
0 = All packets received are ignored
 2010 Microchip Technology Inc.
DS39935C-page 91
ENC424J600/624J600
REGISTER 9-2:
U-0
ETXSTAT: ETHERNET TRANSMIT STATUS REGISTER
U-0
—
—
U-0
—
R-0
r
R-0
r
R-0
LATECOL
R-0
(1)
MAXCOL
R-0
(1)
EXDEFER(1)
bit 15
bit 8
R-0
(1)
DEFER
R-0
R-0
R-0
r
r
CRCBAD
R-0
R-0
R-0
R-0
COLCNT3(1) COLCNT2(1) COLCNT1(1) COLCNT0(1)
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 15-13
Unimplemented: Read as ‘0’
bit 12-11
Reserved: Ignore on read
bit 10
LATECOL: Transmit Late Collision Status bit(1)
1 = A collision occurred after transmitting more than MACLCONH + 8 bytes. The last transmission was
aborted.
0 = No late collision occurred during the last transmission
bit 9
MAXCOL: Transmit Maximum Collisions Status bit(1)
1 = MACLCONL + 1 collisions occurred while transmitting the last packet. The last transmission was
aborted.
0 = MACLCONL or less collisions occurred while transmitting the last packet
bit 8
EXDEFER: Transmit Excessive Defer Status bit(1)
1 = The medium was busy with traffic from other nodes for more than 24,288 bit times. The last
transmission was aborted.
0 = The MAC deferred for less than 24,288 bit times while transmitting the last packet
bit 7
DEFER: Transmit Defer Status bit(1)
1 = The medium was busy with traffic from other nodes, so the MAC was forced to temporarily defer
transmission of the last packet
0 = No transmit deferral or an excessive deferral occurred while attempting to transmit the last packet
bit 6-5
Reserved: Ignore on read
bit 4
CRCBAD: Transmit CRC Incorrect Status bit
1 = The FCS field of the last packet transmitted did not match the CRC internally generated by the
MAC during transmission
0 = The FCS field of the last packet transmitted was correct or the MAC is configured to append an
internally generated CRC
bit 3-0
COLCNT<3:0>: Transmit Collision Count Status bits(1)
Number of collisions that occurred while transmitting the last packet.
Note 1:
Applicable in Half-Duplex mode only; collisions and deferrals are not possible in Full-Duplex mode.
DS39935C-page 92
 2010 Microchip Technology Inc.
ENC424J600/624J600
REGISTER 9-3:
ESTAT: ETHERNET STATUS REGISTER
R-0
R-0
R-0
R-0
R-0
R-0
R-0
R-0
INT
FCIDLE
RXBUSY
CLKRDY
r
PHYDPX
r
PHYLNK
bit 15
bit 8
R-0
R-0
R-0
R-0
R-0
R-0
R-0
R-0
PKTCNT7
PKTCNT6
PKTCNT5
PKTCNT4
PKTCNT3
PKTCNT2
PKTCNT1
PKTCNT0
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 15
INT: Interrupt Pending Status bit
1 = One of the EIR bits is set and enabled by the EIE register. If INTIE (EIE<15>) is set, the INT pin is
also driven low.
0 = No enabled interrupts are currently pending. The INT pin is being driven high.
bit 14
FCIDLE: Flow Control Idle Status bit
1 = Internal flow control state machine is Idle. It is safe to change the FCOP (ECON1<7:6>) and
FULDPX (MACON2<0>) bits.
0 = Internal flow control state machine is busy. Do not modify the FCOP (ECON1<7:6>) or FULDPX
(MACON2<0>) bits.
bit 13
RXBUSY: Receive Logic Active Status bit
1 = Receive logic is currently receiving a packet. This packet may be discarded in the future if an RX
buffer overflow occurs or a receive filter rejects it, so this bit does not necessarily indicate that an
RX packet pending interrupt will occur.
0 = Receive logic is Idle
bit 12
CLKRDY: Clock Ready Status bit
1 = Normal operation
0 = Internal Ethernet clocks are not running and stable yet. Only the ESTAT and EUDAST registers
should be accessed.
bit 11
Reserved: Ignore on read
bit 10
PHYDPX: PHY Full Duplex Status bit
1 = PHY is operating in Full-Duplex mode
0 = PHY is operating in Half-Duplex mode
bit 9
Reserved: Ignore on read
bit 8
PHYLNK: PHY Linked Status bit
1 = Ethernet link has been established with a remote Ethernet partner
0 = No Ethernet link present
bit 7-0
PKTCNT<7:0>: Receive Packet Count bits
Number of complete packets that are saved in the RX buffer and ready for software processing. Set the
PKTDEC (ECON1<8>) bit to decrement this field.
 2010 Microchip Technology Inc.
DS39935C-page 93
ENC424J600/624J600
NOTES:
DS39935C-page 94
 2010 Microchip Technology Inc.
ENC424J600/624J600
10.0
RECEIVE FILTERS
To minimize the number of frames that the host controller
must process, ENC424J600/624J600 devices incorporate 11 different receive filters to discard unwanted
frames. The following filters are available:
•
•
•
•
•
•
•
•
•
•
•
CRC Error Collection Filter
Runt Error Collection Filter
CRC Error Rejection Filter
Runt Error Rejection Filter
Unicast Collection Filter
Not-Me Unicast Collection Filter
Multicast Collection Filter
Broadcast Collection Filter
Hash Table Collection Filter
Magic Packet™ Collection Filter
Pattern Match Collection Filter
Each filter is software configurable, and can be individually enabled or disabled, using the ERXFCON register
(Register 10-1). Each filter is either a Collection or a
Rejection filter, with incoming frames passing sequentially through each enabled filter. The first filter to make a
definitive decision for a frame takes priority over all
others. Collection filters either force a frame to be
accepted or defer the decision to a lower priority filter.
Similarly, Rejection filters either discard frames or defer
to lower priority filters. Frames that pass through all filters
without specifically being accepted are discarded.
Figure 10-1 demonstrates this decision tree.
 2010 Microchip Technology Inc.
At power-up, the CRC Error Rejection, Runt Error
Rejection, Unicast Collection and Broadcast Collection
filters are enabled, and all others are disabled. With
these settings, the device will only accept Broadcast
frames and frames specifically addressed to the local
MAC address. Invalid frames and those destined for
other nodes will be automatically rejected.
Note 1: The MAC internally processes and filters
Ethernet control frames as they arrive
and before they reach these filters. For
the application to receive Ethernet control
frames, enable the PASSALL option
(MACCON1<1> = 1).
2: If the Ethernet Receive Enable bit, RXEN
(ECON1<0>), is set, the filters may make
an incorrect decision if any of the receive
filters are reconfigured at the exact
moment a new frame is being received.
To avoid this behavior, clear the RXEN bit
prior to changing any receive filter
settings.
DS39935C-page 95
ENC424J600/624J600
REGISTER 10-1:
ERXFCON: ETHERNET RX FILTER CONTROL REGISTER
R/W-0
R/W-0
U-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
HTEN
MPEN
—
NOTPM
PMEN3
PMEN2
PMEN1
PMEN0
bit 15
bit 8
R/W-0
R/W-1
R/W-0
R/W-1
R/W-1
R/W-0
R/W-0
R/W-1
CRCEEN
CRCEN
RUNTEEN
RUNTEN
UCEN
NOTMEEN
MCEN
BCEN
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 15
HTEN: Hash Table Collection Filter Enable bit
1 = Accept packets having a hashed destination address that points to a set bit in the Hash Table(1)
0 = Filter is disabled
bit 14
MPEN: Magic Packet™ Collection Filter Enable bit
1 = Accept packets containing a Magic Packet pattern for the local MAC address(1)
0 = Filter is disabled
bit 13
Unimplemented: Read as ‘0’
bit 12
NOTPM: Pattern Match Inversion Control bit
1 = Pattern Match checksum mismatch required for a successful Pattern Match
0 = Pattern Match checksum match required for a successful Pattern Match
bit 11-8
PMEN<3:0>: Pattern Match Collection Filter Enable bits
When NOTPM = 0:
A packet is accepted by the filter if the pattern checksum matches AND the selected mode’s condition is
true.
When NOTPM = 1:
A packet is accepted by the filter if pattern checksum does not match AND the selected mode’s condition
is true.
1111
.... = Reserved
1010
1001 = Magic Packet for local Unicast address(1)
1000 = Hashed packet destination points to a bit in the Hash Table registers that is set(1)
0111 = Packet destination is not the Broadcast address(1)
0110 = Packet destination is the Broadcast address(1)
0101 = Packet destination is not a Multicast address(1)
0100 = Packet destination is a Multicast address(1)
0011 = Packet destination is not the local Unicast address(1)
0010 = Packet destination is the local Unicast address(1)
0001 = Accept all packets with a checksum match defined by NOTPM(1)
0000 = Filter is disabled
bit 7
CRCEEN: CRC Error Collection Filter Enable bit
1 = Packets with an invalid CRC will be accepted, regardless of all other filter settings
0 = Filter is disabled
Note 1:
2:
This filtering decision can be overridden by the CRC Error Rejection filter and Runt Error Rejection filter
decisions, if enabled, by CRCEN or RUNTEN.
This filtering decision can be overridden by the CRC Error Collection filter and Runt Error Collection filter
decisions, if enabled, by CRCEEN or RUNTEEN.
DS39935C-page 96
 2010 Microchip Technology Inc.
ENC424J600/624J600
REGISTER 10-1:
ERXFCON: ETHERNET RX FILTER CONTROL REGISTER (CONTINUED)
bit 6
CRCEN: CRC Error Rejection Filter Enable bit
1 = Packets with an invalid CRC will be discarded(2)
0 = Filter is disabled
bit 5
RUNTEEN: Runt Error Collection Filter Enable bit
1 = Accept packets that are 63 bytes or smaller, regardless of all other filter settings
0 = Filter is disabled
bit 4
RUNTEN: Runt Error Rejection Filter Enable bit
1 = Discard packets that are 63 bytes or smaller(2)
0 = Filter is disabled
bit 3
UCEN: Unicast Destination Collection Filter Enable bit
1 = Accept packets with a destination address matching the local MAC address(1)
0 = Filter is disabled
bit 2
NOTMEEN: Not-Me Unicast Destination Collection Filter Enable bit
1 = Accept packets with a Unicast destination address that does not match the local MAC address(1)
0 = Filter is disabled
bit 1
MCEN: Multicast Destination Collection Filter Enable bit
1 = Accept packets with a Multicast destination address(1)
0 = Filter is disabled
bit 0
BCEN: Broadcast Destination Collection Filter Enable bit
1 = Accept packets with a Broadcast destination address of FF-FF-FF-FF-FF-FF(1)
0 = Filter is disabled
Note 1:
2:
This filtering decision can be overridden by the CRC Error Rejection filter and Runt Error Rejection filter
decisions, if enabled, by CRCEN or RUNTEN.
This filtering decision can be overridden by the CRC Error Collection filter and Runt Error Collection filter
decisions, if enabled, by CRCEEN or RUNTEEN.
 2010 Microchip Technology Inc.
DS39935C-page 97
ENC424J600/624J600
FIGURE 10-1:
RECEIVE FILTER DECISION TREE
Packet Arrives
CRCEEN set?
Yes
No
RUNTEEN set?
Yes
Yes
No
No
CRC is valid?
Yes
Length < 64
bytes?
Yes
No
CRCEN set?
RUNTEN set?
UCEN set?
Yes
No
NOTMEEN set?
MCEN set?
Yes
Yes
Yes
Yes
DS39935C-page 98
Pattern
Match?(1)
Yes
Broadcast
destination?
Yes
Hash Table
bit set?
Yes
No
Yes
No
Reject or
Disabled
Multicast
destination?
No
No
MPEN set?
Yes
No
No
HTEN set?
Unicast for
someone else?
No
No
BCEN set?
Yes
Unicast for me?
No
No
Note 1:
Yes
No
No
Discard Packet
Length < 64
bytes?
No
Yes
Yes
No
CRC is valid?
Magic Packet™
for me?
Yes
No
Accept
Accept Packet
For details on the Pattern Match filter, refer to Section 10.11 “Pattern Match Collection Filter”.
 2010 Microchip Technology Inc.
ENC424J600/624J600
10.1
CRC Error Collection Filter
The CRC Error Collection filter allows applications to
accept frames with an invalid Frame Check Sequence
(FCS). This filter is primarily intended for performing
network, cable and layout noise immunity diagnostics.
The filter computes the CRC over incoming frame data
and compares the result with the FCS appended at the
end of each frame. If the computed CRC does not
match the FCS, the filter will accept the frame. If the
CRC is correct or the CRC Error Collection filter is
disabled, the frame passes through to the next lower
priority filter.
This filter is disabled at power-up. To enable the filter,
set CRCEEN (ERXFCON<7>). Enabling this filter will
cause frames with bit transmission errors and/or invalid
data to be accepted into the packet buffer. To comply
with IEEE 802.3 specifications, this filter should be
disabled.
10.2
This filter is enabled at power-up. To disable this filter,
clear CRCEN (ERXFCON<6>). If the filter is disabled,
all frames will be passed on to the next lower priority
filter, regardless of CRC validity.
Note:
10.4
Enable this filter for normal IEEE 802.3
compliant operation.
Runt Error Rejection Filter
The Runt Error Rejection filter checks the length of
each incoming frame. If the length of the frame is less
than the Ethernet minimum of 64 bytes, the frame will
be discarded. Frames of 64 bytes or larger will be
passed on to the next filter.
This filter is enabled at power-up. To disable this filter,
clear RUNTEN (ERXFCON<4>). If the filter is disabled,
all frames will be passed on to the next lower priority
filter, regardless of length.
Note:
Runt Error Collection Filter
Enable this filter for normal IEEE 802.3
compliant operation.
The Runt Error Collection filter allows applications to
accept frames shorter than 64 bytes (counting from the
start of the Ethernet source address to the end of the
Frame Check Sequence, inclusive). Runt packets are
ordinarily generated by early half-duplex collisions and
should not be treated as valid packets. This filter is
primarily intended for detecting duplex mismatches or
performing network utilization diagnostics.
10.5
The filter checks the length of each frame and accepts
any frame with a length of 63 or fewer bytes. Frames
that are 64 bytes or longer are passed on to the next
lower priority filter.
This filter is enabled at power-up. To disable this filter,
clear UCEN (ERXFCON<3>). If the filter is disabled, all
frames will be passed on to the next lower priority filter,
regardless of destination address.
This filter is disabled at power-up. To enable the filter,
set RUNTEEN (ERXFCON<5>). If the filter is disabled,
all frames will be passed on to the next lower priority
filter, regardless of length.
To comply with IEEE 802.3 specifications and properly
discard collision fragments, this filter should be
disabled.
10.3
CRC Error Rejection Filter
The CRC Error Rejection filter verifies the Frame
Check Sequence of incoming frames. If the CRC is
invalid, the frame is discarded. Frames with a valid
CRC will be passed on to the next filter.
The MAC truncates received frames if they exceed the
length specified by the MAC maximum frame length
register, MAMXFL. Because the Frame Check
Sequence is always transmitted as the last four bytes
of any Ethernet frame, reception of an oversize frame
that becomes truncated will almost always result in an
invalid CRC. When enabled, the CRC Error Rejection
filter will discard these truncated frames, as well as
collision fragments, and other frames that become
corrupted during transmission.
 2010 Microchip Technology Inc.
Unicast Collection Filter
The Unicast Collection filter checks the destination
address of each incoming frame. If the destination
address exactly matches the local MAC address,
defined by the MAADR registers, the frame will be
accepted. If there is a mismatch, the frame will be
passed on to the next filter.
10.6
Not-Me Unicast Collection Filter
The Not-Me Unicast Collection filter checks the destination address of incoming frames. If the destination
address is a Unicast address, but does not exactly
match the contents of the MAADR registers, the frame
will be accepted. This will include any frame specifically
addressed to another station, but will not include Multicast or Broadcast frames. If the packet is a Multicast,
Broadcast or Unicast frame for the local device, the
frame will be passed on to the next filter.
This filter is disabled at power-up. To enable this filter,
set NOTMEEN (ERXFCON<2>). If the filter is disabled,
all frames will be passed on to the next lower priority
filter, regardless of destination address.
DS39935C-page 99
ENC424J600/624J600
10.7
Multicast Collection Filter
turn, points to a location in a table formed by the Ethernet Hash Table registers, ETH1 through ETH4. If the bit
in that location is set, the packet meets the Hash Table
filter criteria and is accepted. The specific pointer
values for each bit location in the table are shown in
Table 10-1.
The Multicast Collection filter checks the destination
address of incoming frames. If the Least Significant bit
(LSb) of the first byte of the destination address is set,
the frame will be accepted. This represents all Multicast
frames. If the frame has a Unicast destination, it will be
passed on to the next filter.
An example of the Hash Table operation is shown in
Example 10-1. In this case, the destination address,
01-00-00-00-01-2C, produces a Hash Table Pointer
value of 34h, which points to bit 4 of ETH4. If this bit is
‘1’, the packet will be accepted. If this Hash Table bit is
‘0’, the packet will be passed to the next lower priority
filter.
This filter is disabled at power-up. To enable this filter,
set MCEN (ERXFCON<1>). If the filter is disabled, all
frames will be passed on to the next lower priority filter,
regardless of destination address.
10.8
Broadcast Collection Filter
By extension, if every bit in the Hash Table is set, the
filter criteria will always be met, so all packets will be
accepted if no higher priority filter has rejected the
packet. Similarly, clearing every bit in the Hash Table
registers means that the filter criteria will never be met,
so all packets will be passed on to the next lower
priority filter.
The Broadcast Collection filter checks the destination
address of incoming frames. If the destination address
is FF-FF-FF-FF-FF-FF, the frame will be accepted.
Frames matching this filter are designated as being
broadcast to all nodes that receive them. All frames
with other address values will be passed on to the next
filter.
This filter is enabled at power-up. To disable this filter,
clear BCEN (ERXFCON<0>). If the filter is disabled, all
frames will be passed on to the next lower priority filter,
regardless of destination address.
This filter is disabled at power-up. To enable this filter,
set HTEN (ERXFCON<15>). If the filter is disabled, all
frames will be passed on to the next lower priority filter,
regardless of destination address or Hash Table
register values.
10.9
EXAMPLE 10-1:
Hash Table Collection Filter
The Hash Table filter accepts frames based on their destination address, and is configurable for up to 64 different
hash values. This filter allows the device to accept
frames for multiple destination addresses (without
accepting all Not-Me traffic as described in
Section 10.6 “Not-Me Unicast Collection Filter”). It
can also be used to accept traffic for one or more
specific Multicast groups (without accepting all Multicast traffic as described in Section 10.7 “Multicast
Collection Filter”). Note that Hash Table collisions are
possible, so applications should still verify the MAC
address of accepted frames. This filter simply reduces
the amount of incoming traffic for these applications.
Packet Destination Address:
01-00-00-00-01-2C (hex)
Result of CRC-32 with 4C11DB7h:
1101 1010 0000 1011 0100 0101 0111 0101
(binary)
Pointer Derived from bits<28:23> of CRC Result:
110100 (binary) or 34 (hex)
The filter performs a 32-bit CRC over the six destination address bytes in the packet, using the polynomial,
4C11DB7h. From the resulting 32-bit binary number, a
6-bit value is taken from bits<28:23>. This value, in
TABLE 10-1:
Register
DERIVING A HASH TABLE
LOCATION
Corresponding Hash Table Location:
EHT4<4>
BIT ASSIGNMENTS IN HASH TABLE REGISTERS
Bit Numbers in Hash Table
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
EHT1
0F
0E
0D
0C
0B
0A
09
08
07
06
05
04
03
02
01
00
EHT2
1F
1E
1D
1C
1B
1A
19
18
17
16
15
14
13
12
11
10
EHT3
2F
2E
2D
2C
2B
2A
29
28
27
26
25
24
23
22
21
20
EHT4
3F
3E
3D
3C
3B
3A
39
38
37
36
35
34
33
32
31
30
DS39935C-page 100
 2010 Microchip Technology Inc.
ENC424J600/624J600
10.10 Magic Packet™ Collection Filter
The Magic Packet filter scans all packet contents for a
Magic Packet pattern for the local MAC address. If a
valid Magic Packet pattern is found, then the frame will
be accepted. The Magic Packet pattern consists of a
sync pattern of six FFh bytes, followed by the MAC
address of the station the Magic Packet is intended for,
repeated 16 times. See Figure 10-2 for a sample Magic
FIGURE 10-2:
Packet. This pattern may be located anywhere within
the packet. Other fields in the packet, such as the
destination address or bytes preceding or following the
Magic Packet pattern, are ignored.
This filter is disabled at power-up. To enable this filter,
set MPEN (ERXFCON<14>). If the filter is disabled or
the received packet is not a Magic Packet, the frame
will be passed to the next lower priority filter.
SAMPLE MAGIC PACKET™ FORMAT
Received
Data
Field
FF FF FF FF FF FF
00 01 1A 00 CA FE
08 00
Comments
Destination Address
Source Address
Type/Length
09 0A 0B 0C 0D 0E
FF FF FF FF FF 00
Sync Pattern
FF FF FF FF FF FF
00
00
00
00
00
00
00
00
00
00
00
00
00
00
00
00
04
04
04
04
04
04
04
04
04
04
04
04
04
04
04
04
A3
A3
A3
A3
A3
A3
A3
A3
A3
A3
A3
A3
A3
A3
A3
A3
11
11
11
11
11
11
11
11
11
11
11
11
11
11
11
11
23
23
23
23
23
23
23
23
23
23
23
23
23
23
23
23
33
33
33
33
33
33
33
33
33
33
33
33
33
33
33
33
Data
Sixteen Repeats of
the MAADR MAC Address
19 1A 1B 1C 1D 1E
EF 54 32 10
FCS
 2010 Microchip Technology Inc.
DS39935C-page 101
ENC424J600/624J600
10.11 Pattern Match Collection Filter
The Pattern Match filter accepts frames that match or
do not match a specific pattern. This filter is useful for
accepting frames that contain expected data
sequences.
Pattern matching is accomplished by choosing a 64-byte
window within the first 128 bytes of a frame, then
selecting some or all of those bytes for a checksum
calculation. The checksum algorithm is the same as the
TCP/IP checksum calculation described in Section 14.2
“Checksum Calculations”. This checksum is then compared to the EPMCS register and the result is optionally
negated by the NOTPM (ERXFCON<12>) flag.
The Pattern Match filter’s control bits, PMEN<3:0>
(ERXFCON<11:8>), differ from all other filters in that
there are multiple options. The output of the above
match can be ANDed with several other conditions.
This adds significant flexibility to the filter as it can
require both a Pattern Match (or non-match) and other
criteria (such as a Broadcast frame or Hash Table
match).
To use the Pattern Match filter, the host controller must
first program the Pattern Match Offset (EPMO) to
select the 64-byte window to be used. Setting this
register to 0000h selects the first 64 bytes of the frame,
beginning with the first byte of the destination address.
Setting 0006h selects byte numbers, 6 through 69,
beginning with the first byte of the source address. This
window must fall within the first 128 bytes of a frame;
the offset value of 1 is not supported, thus, the valid
values for EPMO are 0, 2-63.
Note that if the frame length is short enough so that the
entire window would not exist in the frame, the filter will
automatically fail to match. This is true even if the
corresponding mask bits are all ‘0’.
Then, the host must select the Pattern Match mask
bytes by using the EPMM registers. Within this 64-byte
window, each byte can be selectively included or
excluded from the checksum computation by setting or
clearing the respective bit in the Pattern Match mask. A
bit set to ‘1’ indicates that the byte is to be included. Data
bytes with corresponding mask bits set to ‘0’ are
completely removed for the purpose of the checksum
calculation (as opposed to treating the data bytes as
zero).
DS39935C-page 102
Next, write the expected checksum to the EPMCS register. To select frames that match the checksum, clear
NOTPM (ERXFCON<12>). To select only frames that
fail to match the checksum, set NOTPM to ‘1’. Finally,
set the PMEN bits to ‘0001b’ to require only the Pattern
Match criteria, or one of the other values to add
additional conditions.
For example, to filter all frames having a particular
source MAC address of 00-04-A3-FF-FF-FF:
1.
2.
3.
4.
Program the Pattern Match offset to 0000h.
Set bits, 6-11, of EPMM1 (assuming all other
mask bits are ‘0’).
Program the EPMCS register with a checksum
value of 5BFCh.
Clear NOTPM to require an exact match.
Note that the offset is not programmed to 0006h and the
EPMM1<5:0> bits are not set; the checksum would still
be 5BFCh. However, in this second case, frames less
than 70 bytes would never meet the Pattern Match
criteria because there would not be a complete 64-byte
window beginning at offset position, 0006h. Another
example of a Pattern Match filter is illustrated in
Figure 10-3.
The Pattern Match Collection filter is disabled at
power-up. Because this filter has the lowest priority of
all receive filters, if this filter is disabled or the packet
does not meet the configured Pattern Match criteria,
the packet is automatically discarded.
10.12 Promiscuous Mode
To accept all incoming frames regardless of content
(Promiscuous mode), set the CRCEN, RUNTEN, UCEN,
NOTMEEN and MCEN bits. Disable all other filters.
To accept absolutely all recognizable Ethernet frames,
including those with errors, set PASSALL
(MACCON1<1>) to ‘1’ and set UCEN, NOTMEEN and
MCEN in ERXFCON.
In any mode, frames which cannot fit in the receive
buffer, or would cause the PKTCNT field (ESTAT<7:0>)
to overflow, are still discarded.
 2010 Microchip Technology Inc.
ENC424J600/624J600
FIGURE 10-3:
SAMPLE PATTERN MATCH FORMAT
Input Configuration:
EPMO = 0006h
EPMM4:EPMM1 = 0000000000001F0Ah
EPMCS = 563Fh
Field
DA
SA
Type/Length
Data
FCS
Received
Data
11 22 33 44 55 66 77 88 99 AA BB CC 00 5A
09 0A 0B 0C 0D . . . 40 . . . FE 45 23 01
Byte #
0 1 2 3 4 5
14 15 16 17 18 . . . 69 . . .
6 7 8 9 10 11
12 13
Bytes used for
Checksum Computation
64-Byte Window used
for Pattern Match
Values used for Checksum Computation = {88h, AAh, 09h, 0Ah, 0Bh, 0Ch, 0Dh, 00h}
(00h padding byte added by hardware)
Note:
Received data is shown in hexadecimal. Byte numbers are shown in decimal format.
 2010 Microchip Technology Inc.
DS39935C-page 103
ENC424J600/624J600
NOTES:
DS39935C-page 104
 2010 Microchip Technology Inc.
ENC424J600/624J600
11.0
FLOW CONTROL
Flow control provides a mechanism for network
stations to temporarily stop transmission of data to
themselves. This feature is commonly used to prevent
buffer overruns while receiving data.
ENC424J600/624J600 devices are capable of both
automatic and manual flow control. The hardware can
advertise when it is temporarily unable to receive data
and delay transmissions when a remote system does
the same. Flow control is supported for both full and
half-duplex links. It can either be initiated manually by
software, or configured to enable automatically when
insufficient space remains in the receive buffer
memory.
Flow control operation is configured by the FCOP<1:0>
bits (ECON1<7:6>), the AUTOFC bit (ECON2<7>), the
RXPAUS and PASSALL bits (MACON1<2:1>), and the
EPAUS and ERXWM registers in some modes.
Note:
11.1
Flow control is an optional portion of the
IEEE 802.3 specification and may not be
implemented on all remote devices.
Modes of Operation
Flow control operation differs between full and
half-duplex links. Both modes are supported, but it is
important to understand the difference before enabling
flow control in an application.
11.1.1
HALF-DUPLEX MODE
When the link is operating in Half-Duplex mode, flow
control operates by jamming the network. The node
wishing to inhibit transmissions to itself sends a
preamble pattern of alternating ones and zeros (55h)
on the medium; this is also known as asserting back
pressure on the link. Since the link is operating under
Half-Duplex mode, all connected nodes must wait
before transmitting. If a node does transmit, compliant
nodes will detect the collision and wait until the
jamming stops to retransmit. This effectively jams the
network until flow control is disabled.
If a frame is to be transmitted while flow control is
enabled, the ENCX24J600 will stop jamming, wait the
standard Inter-Packet Gap (IPG) delay, then attempt to
transmit. Because all traffic was previously jammed,
several nodes may begin transmitting and several
collisions may occur. The hardware will transmit and
resume jamming as soon as possible, but it is feasible
for other nodes to transmit packets before this
happens. This limitation of flow control in half-duplex
operation cannot be avoided.
 2010 Microchip Technology Inc.
Given the detrimental effect that back pressure based
flow control inflicts on a network, along with the
possible lack of effectiveness, it is recommended that
flow control be avoided in Half-Duplex mode unless the
application is used in a closed network environment
with proper testing.
When operating in Half-Duplex mode, setting
FCOP<1:0> to ‘00’ disables the flow control. Any other
combination enables flow control and causes the
device to jam the network.
11.1.2
FULL-DUPLEX MODE
Flow control for full-duplex links is much more robust.
Instead of jamming the network, a station can send a
pause control frame to the remote system. The pause
frame is directed to a special Multicast destination
address (01-08-C2-00-00-01) and indicates how long
the remote node should wait before transmitting again.
This time is expressed in units of pause quanta, where
one pause quanta is equal to 512 bit times.
While a station is silenced or paused, reception is still
enabled. If another pause control frame arrives, any
previous value is discarded and the timer restarts using
the new pause time value. If the received control frame
has a timer value of zero, the pause is terminated and
transmission resumes immediately.
When operating in Full-Duplex mode, each combination of FCOP<1:0> has a different effect on transmitting
control frames. These combinations are discussed in
Section 11.2.1 “Manual Flow Control”.
11.1.3
TRANSMITTING AND RECEIVING
PAUSE CONTROL FRAMES
The ENCX24J600 automatically processes incoming
pause control frames without application intervention.
When a pause control frame is received, the MAC
internally sets the pause timer. Transmission is inhibited while the timer is active. If an application attempts
to transmit a packet during this time, the transmission
logic will stall until the time expires (i.e., TXRTS will
stay set for longer than normal).
Pause control frames are normally filtered out by the
MAC and are not written to the receive buffer. Setting the
PASSALL bit (MACON1<1>) alters this behavior and
causes these frames to pass through the receive filters.
If the frame is accepted, it will be written to the receive
buffer. However, setting PASSALL will also cause the
MAC to not process the pause control frame. The transmission logic will allow immediate transmission without
regard to the remote pause requests.
Before using either automatic or manual flow control,
set the pause time value with the EPAUS register. This
value controls the pause time value that is transmitted
with each pause control frame. Each unit of pause
quanta in this register is equal to 512 bit times.
DS39935C-page 105
ENC424J600/624J600
11.2
Note:
11.2.1
Manual and Automatic Flow
Control
When flow control is used in conjunction
with auto-negotiation, also set the ADPAUS
bits (PHANA<11:10>) to ‘01’ during initialization. See Section 12.0 “Speed/Duplex
Configuration and Auto-Negotiation” for
more information.
MANUAL FLOW CONTROL
Manual flow control is enabled by default on device
power-up and whenever the AUTOFC bit (ECON2<7>)
is cleared. Setting AUTOFC disables manual flow
control.
To begin manual flow control in Full-Duplex mode, set
FCOP<1:0> to one of the following combinations:
• Idle (‘00’): Flow control is disabled or Idle.
• Single Pause (‘01’): Transmit one pause frame for
the time indicated in EPAUS; automatically
returns to the Idle state (‘00’).
• Continuous Pause (‘10’): Periodically transmit
pause frames using the value indicated in EPAUS
for an indefinite time; must be terminated using
End (‘11’).
• End (‘11’): Transmit one pause frame with a timer
of 0000h, then return to the Idle state (‘00’).
11.2.2
When the AUTOFC bit is set, the ENCX24J600 automatically initiates flow control operation when the
amount of data in the receive buffer crosses an upper
threshold value. Flow control automatically terminates
once the amount of pending data shrinks below a lower
threshold. These thresholds, or “watermarks”, are
determined by the upper and lower bytes (respectively)
of the Receive Watermark register, ERXWM. These
thresholds represent 96-byte blocks.
For example, setting the RXFWM bits to 20h and the
RXEWM bits to 10h initiates flow control when more
than 3072 bytes of data are present in the buffer. Flow
control terminates when fewer than 1536 bytes of data
are in the buffer.
In Automatic mode, the value of FCOP<1:0> is
controlled by the device and must not be changed by
software. These bits, however, can be used as status
bits to determine what state the automatic flow control
engine is in. A value of ‘10’ indicates flow control is
active, while ‘00’ indicates that flow control is Idle.
To use automatic flow control:
1.
2.
In Half-Duplex mode, set FCOP<1:0> to ‘10’ to begin
flow control and to ‘00’ to terminate flow control.
3.
4.
Set the EPAUS register to indicate how many
pause quanta should be specified in each
control frame. It is recommended that the default
value be used.
Set RXFWM<7:0> (ERXWM<15:8>) to indicate
when flow control is to begin. When this number
of 96-byte blocks is consumed in the receive
buffer, the device considers its receive buffer to
be full and initiates flow control. Use the default
value of 16 if the full threshold is to be set at
1536 bytes.
Set RXEWM<7:0> (ERXWM<7:0>) to indicate
when flow control is to end. When the number of
occupied 96-byte blocks falls below this level,
the device considers its receive buffer to be
empty enough to receive more data. Use the
default value of 15 if the empty threshold is to be
set at 1440 bytes.
Set AUTOFC (ECON2<7>) to give control of the
FCOP<1:0> bits to the automatic flow control
hardware.
Note:
DS39935C-page 106
AUTOMATIC FLOW CONTROL
Setting RXFWM to be equal to RXEWM
(i.e., no hysteresis between full and empty)
is not permitted. For automatic flow control
to operate correctly, RXEWM must always
be at least one less than RXFWM, implying
at least 96 bytes of hysteresis.
 2010 Microchip Technology Inc.
ENC424J600/624J600
REGISTER 11-1:
MACON1: MAC CONTROL REGISTER 1
R/W-x
R/W-0
U-0
U-0
R/W-0
R/W-0
R/W-0
R/W-0
r
r
—
—
r
r
r
r
bit 15
bit 8
U-0
U-0
U-0
R/W-0
R/W-1
R/W-1
R/W-0
R/W-1
—
—
—
LOOPBK
r
RXPAUS
PASSALL
r
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 15-14
Reserved: Write as ‘0’
bit 13-12
Unimplemented: Read as ‘0’
bit 11-8
Reserved: Write as ‘0’
x = Bit is unknown
bit 7-5
Unimplemented: Read as ‘0’
bit 4
LOOPBK: MAC Loopback Enable bit
1 = Transmitted packets are looped back inside the MAC before reaching the PHY
0 = Normal operation
bit 3
Reserved: Write as ‘1’
bit 2
RXPAUS: Pause Control Frame Reception Enable bit
1 = Inhibit transmissions when pause control frames are received (normal operation)
0 = Ignore pause control frames which are received
bit 1
PASSALL: Pass All Received Frames Enable bit
1 = Control frames received by the MAC are written into the receive buffer if not filtered out
0 = Control frames are discarded after being processed by the MAC (normal operation)
bit 0
Reserved: Write as ‘1’
 2010 Microchip Technology Inc.
DS39935C-page 107
ENC424J600/624J600
NOTES:
DS39935C-page 108
 2010 Microchip Technology Inc.
ENC424J600/624J600
12.0
SPEED/DUPLEX
CONFIGURATION AND
AUTO-NEGOTIATION
ENC424J600/624J600 devices are capable of operation
at 10Base-T and 100Base-TX speeds in Half-Duplex
and Full-Duplex modes for each. The speed and Duplex
mode can be selected manually, or the part can be
configured to automatically select the optimum link
parameters based on the capabilities of the link partner.
When operating in 10Base-T mode, the part also
compensates for incorrect polarity on the TPIN+/- pins
(100Base-TX signalling is non-polarized).
In half-duplex operation, only one Ethernet controller
may transmit on the physical medium at any given time.
If the host controller initiates a transmission while
another device is transmitting, the ENCX24J600 will
delay until the remote transmitter finishes its packet.
Other devices on the medium should do the same while
the ENCX24J600 is transmitting. If two controllers
begin transmitting at about the same time, a collision
will occur. In this case, the data on the medium is
corrupt; the ENCX24J600 aborts transmission and
attempts to retransmit later.
In full-duplex operation, both nodes may transmit
simultaneously, so collisions do not occur. For details
about transmitting packets, including collision detection
and correction, refer to Section 9.1 “Transmitting
Packets”.
Speed and Duplex modes are configured in the
PHCON1 register (Register 12-1). The PHSTAT1,
PHSTAT2 and PHSTAT3 registers (Registers 12-2
through 12-4) provide additional information about the
status of the link. The PHANA, PHANLPA and PHANE
registers (Registers 12-5 through 12-7) contain
information about auto-negotiation status and
configuration.
12.1
Manual Configuration
Speed and Duplex modes can be manually selected by
disabling auto-negotiation. Manual configuration is
enabled by clearing the ANEN bit (PHCON1<12>).
When manual configuration is used, both the Speed
and Duplex mode must be selected. Set the SPD100
bit (PHCON1<13>) to select 100Base-TX operation or
clear SPD100 to select 10Base-T mode. Set the
PFULDPX bit (PHCON1<8>) to configure Full-Duplex
mode or clear PFULDPX to use half-duplex operation.
 2010 Microchip Technology Inc.
After reconfiguring the Speed and Duplex modes,
update the MACON2, MACLCON, MAIPG and
MABBIPG registers as described in Section 8.9 “After
Link Establishment”.
12.2
Auto-Negotiation
Auto-negotiation allows Ethernet devices to agree
upon the fastest supported transmission rate. When an
Ethernet link is broken, a series of Fast Link Pulses
(FLPs) are transmitted periodically to initiate a link.
Among other things, these pulses encode information
about the node’s speed and duplex capabilities.
If a remote partner exists and supports auto-negotiation,
it will reply with a burst of FLPs to advertise its own link
capabilities. If both devices support 100Base-TX full
duplex, the link will be established and that mode will be
used. Otherwise, the link falls back to 100Base-TX half
duplex, 10Base-T full duplex or 10Base-T half duplex, in
that order.
If the remote link partner does not support autonegotiation, the device will use an algorithm known as
Parallel Detection to determine if the link partner is a
10Base-T device or 100Base-TX device. Parallel
Detection will optimally resolve the operating speed,
however, it will not have any means of learning the
duplex state of the remote node. Therefore, the
ENCX24J600 PHY will always resort to the half-duplex
state when auto-negotiation is not available. A duplex
mismatch will occur if the remote device is operating in
Full-Duplex mode. To determine whether or not the
remote link supports auto-negotiation, check the value
of the LPANABL bit (PHANE<0>).
Auto-negotiation is enabled by default at power-up, but
can be disabled by clearing the ANEN bit. To restart the
auto-negotiation process, set RENEG (PHCON1<9>).
After setting RENEG, the hardware automatically clears
this bit to ‘0’ immediately.
During auto-negation, the information in the PHANA
register is advertised to the link partner by transmitting
the information encoded in the Fast Link Pulses. The
ANDONE bit (PHSTAT1<5>) is set by the hardware
when the auto-negotiation process completes. The
value of SPDDPX<2:0> (PHSTAT3<4:2>) indicates
which operation mode has been selected. The remote
link partner’s capabilities are also stored in the
PHANLPA register.
Note:
When auto-negotiation is enabled,
SPD100 (PHCON1<13>) and PFULDPX
(PHCON1<8>) are control only bits. They
have no effect on Speed or Duplex modes
and do not indicate the current selection
when read.
DS39935C-page 109
ENC424J600/624J600
When LINKIF link status change interrupt flag is set, it
means auto-negotiation or parallel detection is
complete. Once auto-negotiation is complete, the MAC
registers related to Duplex mode must be reconfigured.
Determine the new Duplex mode by reading the
PHYDPX bit (ESTAT<10>). Once this is done, update
REGISTER 12-1:
R/W-0
PRST
the MACON2, MACLCON, MAIPG and MABBIPG
registers as described in Section 8.9 “After Link
Establishment”.
PHCON1: PHY CONTROL REGISTER 1
R/W-0
PLOOPBK
R/W-0
SPD100(1)
R/W-1
ANEN
R/W-0
PSLEEP
R/W-0
r
R/W-0
RENEG
R/W-0
PFULDPX(1)
bit 15
bit 8
R/W-0
R-0
R-0
R-0
R-0
R-0
R-0
R-0
r
r
r
r
r
r
r
r
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 15
PRST: PHY Reset bit
1 = Perform PHY Reset. Hardware automatically clears this bit to ‘0’ when the Reset is complete.
0 = PHY is not in Reset (normal operation)
bit 14
PLOOPBK: PHY Loopback Enable bit
1 = Loopback is enabled
0 = Normal operation
bit 13
SPD100: PHY Speed Select Control bit(1)
1 = 100 Mbps
0 = 10 Mbps
bit 12
ANEN: PHY Auto-Negotiation Enable bit
1 = Auto-negotiation is enabled. SPD100 and PFULDPX are ignored.
0 = Auto-negotiation is disabled. SPD100 and PFULDPX control the operating speed and duplex.
bit 11
PSLEEP: PHY Sleep Enable bit
1 = PHY is powered down
0 = Normal operation
bit 10
Reserved: Write as ‘0’, ignore on read
bit 9
RENEG: Restart Auto-Negotiation Control bit
1 = Restart the auto-negotiation process. Hardware automatically clears this bit to ‘0’ when the
auto-negotiation process starts.
0 = Normal operation
bit 8
PFULDPX: PHY Duplex Select Control bit(1)
1 = Full duplex
0 = Half duplex
bit 7
Reserved: Write as ‘0’, ignore on read
bit 6-0
Reserved: Ignore on read
Note 1:
Applicable only when auto-negotiation is disabled (ANEN = 0).
DS39935C-page 110
 2010 Microchip Technology Inc.
ENC424J600/624J600
REGISTER 12-2:
PHSTAT1: PHY STATUS REGISTER 1
R-0
R-1(1)
R-1(1)
R-1(1)
R-1(1)
R-0
R-0
R-0
r
FULL100
HALF100
FULL10
HALF10
r
r
r
bit 15
bit 8
R-0
R-0
R-0
R/LH-0
R-1(1)
R/LL-0
R-0
R-1(1)
r
r
ANDONE
LRFAULT
ANABLE
LLSTAT
r
EXTREGS
bit 7
bit 0
Legend:
LL = Latch Low bit
U = Unimplemented bit, read as ‘0’
R = Readable bit
W = Writable bit
LH = Latch High bit
LL = Latch-Low bit
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 15
Reserved: Read as ‘0’
bit 14
FULL100: 100Base-TX Full-Duplex Ability Status bit
1 = PHY is capable of 100Base-TX full-duplex operation(1)
bit 13
HALF100: 100Base-TX Half-Duplex Ability Status bit
1 = PHY is capable of 100Base-TX half-duplex operation(1)
bit 12
FULL10: 10Base-T Full-Duplex Ability Status bit
1 = PHY is capable of 10Base-T full-duplex operation(1)
bit 11
HALF10: 10Base-T Half-Duplex Ability Status bit
1 = PHY is capable of 10Base-T half-duplex operation(1)
bit 10-6
Reserved: Ignore on read
bit 5
ANDONE: Auto-Negotiation Done Status bit
1 = Auto-negotiation is complete
0 = Auto-negotiation is disabled or still in progress
bit 4
LRFAULT: Latching Remote Fault Condition Status bit
1 = Remote Fault condition has been detected. This bit latches high and automatically returns to ‘0’
after PHSTAT1 is read.
0 = No remote Fault has been detected since the last read of PHSTAT1
bit 3
ANABLE: Auto-Negotiation Ability Status bit
1 = PHY is capable of auto-negotiation(1)
bit 2
LLSTAT: Latching Link Status bit
1 = Ethernet link is established and has stayed continuously established since the last read of
PHSTAT1
0 = Ethernet link is not established or was not established for a period since the last read of PHSTAT1
bit 1
Reserved: Ignore on read
bit 0
EXTREGS: Extended Capabilities Registers Present Status bit
1 = PHY has extended capability registers at addresses, 16 thru 31(1)
Note 1:
This is the only valid state for this bit; a ‘0’ represents an invalid condition.
 2010 Microchip Technology Inc.
DS39935C-page 111
ENC424J600/624J600
REGISTER 12-3:
PHSTAT2: PHY STATUS REGISTER 2
R/W-x
R/W-x
R/W-x
R/W-x
R/W-x
R/W-x
R/W-x
R/W-x
r
r
r
r
r
r
r
r
bit 15
bit 8
R/W-0
R/W-0
R/W-0
R-0
R-1
R-0
R-1
R-1
r
r
r
PLRITY
r
r
r
r
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 15-5
Reserved: Write as ‘0’, ignore on read
bit 4
PLRITY: TPIN+/- Polarity Status bit (applies to 10Base-T only)
1 = Wiring on the TPIN+/- pins is reversed polarity. PHY internally swaps the TPIN+/- signals to get the
correct polarity.
0 = Wiring on the TPIN+/- is correct polarity
bit 3-0
Reserved: Ignore on read
REGISTER 12-4:
PHSTAT3: PHY STATUS REGISTER 3
R/W-0
R/W-0
R/W-0
R-0
R/W-0
R/W-0
R/W-0
R/W-0
r
r
r
r
r
r
r
r
bit 15
bit 8
R/W-0
R/W-1
R/W-0
R-0
R-0
R-0
R/W-0
R/W-0
r
r
r
SPDDPX2
SPDDPX1
SPDDPX0
r
r
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 15-7
Reserved: Write as ‘0’, ignore on read
bit 6
Reserved: Write as ‘1’
bit 5
Reserved: Write as ‘0’, ignore on read
bit 4-2
SPDDPX<2:0>: Current Operating Speed and Duplex Status bits
111 = Reserved
110 = 100 Mbps, full duplex
101 = 10 Mbps, full duplex
100 = Reserved
011 = Reserved
010 = 100 Mbps, half duplex
001 = 10 Mbps, half duplex
000 = Reserved
bit 1-0
Reserved: Write as ‘0’, ignore on read
DS39935C-page 112
x = Bit is unknown
 2010 Microchip Technology Inc.
ENC424J600/624J600
REGISTER 12-5:
PHANA: PHY AUTO-NEGOTIATION ADVERTISEMENT REGISTER
R-0
R-0
R/W-0
R-0
R/W-0
R/W-0
R-0
R/W-1
ADNP
r
ADFAULT
r
ADPAUS1
ADPAUS0
r
AD100FD
bit 15
bit 8
R/W-1
R/W-1
R/W-1
R/W-0
R/W-0
R/W-0
R/W-0
R/W-1
AD100
AD10FD
AD10
ADIEEE4
ADIEEE3
ADIEEE2
ADIEEE1
ADIEEE0
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 15
ADNP: Advertise Next Page Ability bit
1 = Invalid
0 = Local PHY does not support auto-negotiation next page abilities
bit 14
Reserved: Read as ‘0’
bit 13
ADFAULT: Advertise Remote Fault Condition bit
1 = Local PHY has a Fault condition present
0 = Local PHY does not have a Fault condition present
bit 12
Reserved: Read as ‘0’
bit 11-10
ADPAUS<1:0>: Advertise PAUSE Flow Control Ability bits
11 = Local device supports both symmetric PAUSE and asymmetric PAUSE toward local device
10 = Local device supports asymmetric PAUSE toward link partner only
01 = Local device supports symmetric PAUSE only (Normal Flow Control mode)
00 = Local device does not support PAUSE flow control
bit 9
Reserved: Read as ‘0’
bit 8
AD100FD: Advertise 100Base-TX Full-Duplex Ability bit
1 = Local PHY is capable of 100Base-TX full-duplex operation
0 = Local PHY is incapable of 100Base-TX full-duplex operation
bit 7
AD100: Advertise 100Base-TX Half-Duplex Ability bit
1 = Local PHY is capable of 100Base-TX half-duplex operation
0 = Local PHY is incapable of 100Base-TX half-duplex operation
bit 6
AD10FD: Advertise 10Base-T Full-Duplex Ability bit
1 = Local PHY is capable of 10Base-T full-duplex operation
0 = Local PHY is incapable of 10Base-T full-duplex operation
bit 5
AD10: Advertise 10Base-T Half-Duplex Ability bit
1 = Local PHY is capable of 10Base-T half-duplex operation
0 = Local PHY is incapable of 10Base-T half-duplex operation
bit 4-0
ADIEEE<4:0>: Advertise IEEE Standard Selector Field bits
00001 = IEEE 802.3 Std.
All other values reserved by IEEE. Always specify a selector value of ‘00001’ for this device.
 2010 Microchip Technology Inc.
DS39935C-page 113
ENC424J600/624J600
REGISTER 12-6:
PHANLPA: PHY AUTO-NEGOTIATION LINK PARTNER ABILITY REGISTER
R-0
R-0
R-0
R-0
R-0
R-0
R-0
R-0
LPNP
LPACK
LPFAULT
r
LPPAUS1
LPPAUS0
LP100T4
LP100FD
bit 15
bit 8
R-0
R-0
R-0
R-0
R-0
R-0
R-0
R-0
LP100
LP10FD
LP10
LPIEEE4
LPIEEE3
LPIEEE2
LPIEEE1
LPIEEE0
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 15
LPNP: Link Partner Next Page Ability bit
1 = Link partner PHY supports auto-negotiation next page abilities
0 = Link partner PHY does not support auto-negotiation next page abilities
bit 14
LPACK: Link Partner Acknowledge Local PHY Code Word Status bit
1 = Link partner PHY has successfully received the local PHY abilities saved in PHANA
0 = Link partner PHY has not received the local PHY abilities saved in PHANA
bit 13
LPFAULT: Link Partner Remote Fault Condition bit
1 = Link partner PHY has a Fault condition present
0 = Link partner PHY does not have a Fault condition present
bit 12
Reserved: Ignore on read
bit 11-10
LPPAUS<1:0>: Link Partner PAUSE Flow Control Ability bits
11 = Link partner supports both symmetric PAUSE and asymmetric PAUSE toward local device. Link
partner generates and responds to PAUSE control frames. Alternatively, if the local device only
supports asymmetric PAUSE, the link partner will respond to PAUSE control frames, but not
generate any.
10 = Link partner supports asymmetric PAUSE toward local device only; it can transmit PAUSE control
frames, but cannot act upon PAUSE frames sent to it
01 = Link partner supports symmetric PAUSE only, and generates and responds to PAUSE control
frames
00 = Link partner does not support PAUSE flow control
bit 9
LP100T4: Link Partner 100Base-T4 Ability bit
1 = Link partner PHY is capable of operating in 100Base-T4 mode
0 = Link partner PHY is incapable of operating in 100Base-T4 mode
bit 8
LP100FD: Link Partner 100Base-TX Full-Duplex Ability bit
1 = Link partner PHY is capable of 100Base-TX full-duplex operation
0 = Link partner PHY is incapable of 100Base-TX full-duplex operation
bit 7
LP100: Link Partner 100Base-TX Half-Duplex Ability bit
1 = Link partner PHY is capable of 100Base-TX half-duplex operation
0 = Link partner PHY is incapable of 100Base-TX half-duplex operation
bit 6
LP10FD: Link Partner 10Base-T Full-Duplex Ability bit
1 = Link partner PHY is capable of 10Base-T full-duplex operation
0 = Link partner PHY is incapable of 10Base-T full-duplex operation
bit 5
LP10: Link Partner 10Base-T Half-Duplex Ability bit
1 = Link partner PHY is capable of 10Base-T half-duplex operation
0 = Link partner PHY is incapable of 10Base-T half-duplex operation
bit 4-0
LPIEEE<4:0>: Link Partner IEEE Standard Selector Field bits
00001 = IEEE 802.3 Std.
All other values are reserved by IEEE. Remote node should also specify this as the selector value.
DS39935C-page 114
 2010 Microchip Technology Inc.
ENC424J600/624J600
REGISTER 12-7:
PHANE: PHY AUTO-NEGOTIATION EXPANSION REGISTER
R-0
R-0
R-0
R-0
R-0
R-0
R-0
R-0
r
r
r
r
r
r
r
r
bit 15
bit 8
R-0
R-0
R-0
R/LH-0
R-0
R-0
R/LH-0
R-0
r
r
r
PDFLT
r
r
LPARCD
LPANABL
bit 7
bit 0
Legend:
LH = Latch High bit
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 15-5
Reserved: Ignore on read
bit 4
PDFLT: Parallel Detection Fault Status bit
1 = Parallel detection did not detect a valid link partner; automatically cleared when register is read
0 = Parallel detection is still in progress or a valid link partner is connected
bit 3-2
Reserved: Ignore on read
bit 1
LPARCD: Link Partner Abilities Received Status bit
1 = PHANLPA register has been written with a new value from the link partner; automatically cleared
when register is read
0 = PHANLPA contents have not changed since the last read of PHANE
bit 0
LPANABL: Link Partner Auto-Negotiation Able Status bit
1 = Link partner implements auto-negotiation
0 = Link partner does not implement auto-negotiation
 2010 Microchip Technology Inc.
DS39935C-page 115
ENC424J600/624J600
NOTES:
DS39935C-page 116
 2010 Microchip Technology Inc.
ENC424J600/624J600
13.0
INTERRUPTS
ENC424J600/624J600 devices have multiple interrupt
sources tied to a single output pin, allowing the device
to signal the occurrence of events to the host controller.
The interrupt pin is active-low and is designed for use
by host controllers that can detect falling edges.
Interrupts can also be used on a polling basis without
connecting the interrupt pin. To use interrupts in this
manner, monitor the INT bit (ESTAT<15>) on a periodic
basis.
Interrupts are managed by two registers. The EIE register contains the individual interrupt enable bits for
each interrupt driven by the MAC and cryptographic
components. The EIR register holds the individual
interrupt flags. When an interrupt occurs, the
corresponding interrupt flag is set. If the interrupt is
enabled and the INTIE (EIE<15>) global interrupt
enable bit is set, the INT pin is driven low and the INT
flag (ESTAT<15>) becomes set. This logic is shown in
Figure 13-1.
Even when an interrupt is not enabled, its corresponding
interrupt flags are still set when the interrupt condition
occurs. This allows the host controller to poll for certain
lower priority events while using the interrupt pin for
more important tasks.
FIGURE 13-1:
When an enabled interrupt occurs, the INT pin remains
low until all flags causing interrupts are cleared or
masked off (the enable bit is cleared). If more than one
interrupt source is enabled, the host controller must poll
each flag to determine the source(s) of the interrupt. A
good practice is for the host controller to clear the
Global Interrupt Enable bit, INTIE (EIE<15>), immediately after an interrupt event. This causes the interrupt
pin to return to the non-asserted (high) state. Once the
interrupt has been serviced, the INTIE bit is set again
to re-enable interrupts. If a new interrupt occurs while
servicing another, the act of resetting the global enable
bit will cause a new falling edge to occur on the
interrupt pin and ensure that the host does not miss any
events.
When clearing EIR interrupt flags, it is required that bitoriented operations be used. These include Bit Field
Set and Bit Field Clear opcodes for the SPI interface,
and using the Bit Set and Bit Clear registers for the PSP
interfaces. This procedure ensures that interrupts
occurring during the write procedure are not
inadvertently missed.
ENC424J600/624J600 INTERRUPT LOGIC
MODEXIF
MODEXIE
HASHIF
HASHIE
AESIF
AESIE
LINKIF
LINKIE
PKTIF
PKTIE
INT
INTIE
DMAIF
DMAIE
TXIF
TXIE
TXABTIF
TXABTIE
RXABTIF
RXABTIE
PCFULIF
PCFULIE
EIR/EIE
 2010 Microchip Technology Inc.
DS39935C-page 117
ENC424J600/624J600
REGISTER 13-1:
EIR: ETHERNET INTERRUPT FLAG REGISTER
R/W-0
R/W-0
R/W-0
R/W-0
R/W-1
R/W-0
R/W-1
R/W-0
CRYPTEN
MODEXIF
HASHIF
AESIF
LINKIF
r
r
r
bit 15
bit 8
R/W-0
R-0
R/W-0
R-0
R/W-0
R/W-0
R/W-0
R/W-0
r
PKTIF
DMAIF
r
TXIF
TXABTIF
RXABTIF
PCFULIF
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 15
CRYPTEN: Modular Exponentiation and AES Cryptographic Modules Enable bit
1 = All cryptographic engine modules are enabled
0 = Modular exponentiation and AES modules are disabled and powered down; MD5/SHA-1 hashing
is still available
bit 14
MODEXIF: Modular Exponentiation Interrupt Flag bit
1 = Modular exponentiation calculation is complete
0 = No interrupt pending
bit 13
HASHIF: MD5/SHA-1 Hash Interrupt Flag bit
1 = MD5/SHA-1 hash operation is complete
0 = No interrupt pending
bit 12
AESIF: AES Encrypt/Decrypt Interrupt Flag bit
1 = AES encrypt/decrypt operation is complete
0 = No interrupt pending
bit 11
LINKIF: PHY Link Status Change Interrupt Flag bit
1 = PHY Ethernet link status has changed. Read PHYLNK (ESTAT<8>) to determine the current state.
0 = No interrupt pending
bit 10-7
Reserved: Ignore on read, don’t care on write
bit 6
PKTIF: RX Packet Pending Interrupt Flag bit
1 = One or more RX packets have been saved and are ready for software processing. The
PKTCNT<7:0> (ESTAT<7:0>) bits are non-zero. To clear this flag, decrement the PKTCNT bits to
zero by setting PKTDEC (ECON1<8>).
0 = No RX packets are pending
bit 5
DMAIF: DMA Interrupt Flag bit
1 = DMA copy or checksum operation is complete
0 = No interrupt pending
bit 4
Reserved: Ignore on read, don’t care on write
bit 3
TXIF: Transmit Done Interrupt Flag bit
1 = Packet transmission has completed. TXRTS (ECON1<1>) has been cleared by hardware.
0 = No interrupt pending
bit 2
TXABTIF: Transmit Abort Interrupt Flag bit
1 = Packet transmission has been aborted due to an error. Read the ETXSTAT register to determine
the cause. TXRTS (ECON1<1>) has been cleared by hardware.
0 = No interrupt pending
DS39935C-page 118
 2010 Microchip Technology Inc.
ENC424J600/624J600
REGISTER 13-1:
EIR: ETHERNET INTERRUPT FLAG REGISTER (CONTINUED)
bit 1
RXABTIF: Receive Abort Interrupt Flag bit
1 = An RX packet was dropped because there is insufficient space in the RX buffer to store the
complete packet or the PKTCNT field is saturated at FFh
0 = No interrupt pending
bit 0
PCFULIF: Packet Counter Full Interrupt Flag bit
1 = PKTCNT field has reached FFh. Software must decrement the packet counter to prevent the next
RX packet from being dropped.
0 = No interrupt pending
 2010 Microchip Technology Inc.
DS39935C-page 119
ENC424J600/624J600
REGISTER 13-2:
EIE: ETHERNET INTERRUPT ENABLE REGISTER
R/W-1
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
INTIE
MODEXIE
HASHIE
AESIE
LINKIE
r
r
r
bit 15
bit 8
R/W-0
R/W-0
R/W-0
R-1
R/W-0
R/W-0
R/W-0
R/W-0
r
PKTIE
DMAIE
r(1)
TXIE
TXABTIE
RXABTIE
PCFULIE
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 15
INTIE: INT Global Interrupt Enable bit
1 = INT pin is controlled by the INT status bit (ESTAT<15>)
0 = INT pin is driven high
bit 14
MODEXIE: Modular Exponentiation Interrupt Enable bit
1 = Enabled
0 = Disabled
bit 13
HASHIE: MD5/SHA-1 Hash Interrupt Enable bit
1 = Enabled
0 = Disabled
bit 12
AESIE: AES Encrypt/Decrypt Interrupt Enable bit
1 = Enabled
0 = Disabled
bit 11
LINKIE: PHY Link Status Change Interrupt Enable bit
1 = Enabled
0 = Disabled
bit 10-7
Reserved: Write as ‘0’
bit 6
PKTIE: RX Packet Pending Interrupt Enable bit
1 = Enabled
0 = Disabled
bit 5
DMAIE: DMA Interrupt Enable bit
1 = Enabled
0 = Disabled
bit 4
Reserved: Ignore on read, don’t care on write(1)
bit 3
TXIE: Transmit Done Interrupt Enable bit
1 = Enabled
0 = Disabled
bit 2
TXABTIE: Transmit Abort Interrupt Enable bit
1 = Enabled
0 = Disabled
bit 1
RXABTIE: Receive Abort Interrupt Enable bit
1 = Enabled
0 = Disabled
bit 0
PCFULIE: Packet Counter Full Interrupt Enable bit
1 = Enabled
0 = Disabled
Note 1:
x = Bit is unknown
This bit is read-only and cannot be cleared. Hardware does not modify it.
DS39935C-page 120
 2010 Microchip Technology Inc.
ENC424J600/624J600
13.1
Interrupt Sources
ENC424J600/624J600 devices have multiple interrupt
sources, each individually selectable. The various
interrupt sources are described in the following sections.
For any of the following interrupts to propagate out of
the device, the INTIE (EIE<15>) global interrupt enable
must be set.
13.1.1
MODULAR EXPONENTIATION
COMPLETE
The modular exponentiation complete interrupt occurs
when a modular exponentiation operation is completed. This flag is set when MODEXST (ECON1<15>)
is cleared. The interrupt should be cleared by software
once it has been serviced.
To enable the modular exponentiation complete
interrupt, set MODEXIE (EIE<14>).
For more information on the modular exponentiation
feature, refer to Section 15.1 “Modular Exponentiation”.
13.1.2
MD5/SHA-1 HASH COMPLETE
The MD5/SHA-1 hash complete interrupt occurs when
the hashing module completes a block or calculation.
The interrupt flag is required when using the hashing
engine; therefore, the flag must be cleared by software
after the interrupt has been serviced.
To enable the MD5/SHA-1 complete interrupt, set
HASHIE (EIE<13>).
For more information on the MD5/SHA-1 hashing feature,
refer to Section 15.2 “MD5 and SHA-1 Hashing”.
13.1.3
AES COMPLETE
The Advanced Encryption Standard (AES) complete
interrupt occurs when a block has been encrypted or
decrypted using the AES engine. This flag is set when
AESST (ECON1<11>) is cleared. The interrupt should
be cleared by software once it has been serviced.
To enable the AES complete interrupt, set AESIE
(EIE<12>).
For more information on the Advanced Encryption
Standard engine, refer to Section 15.3 “Advanced
Encryption Standard (AES)”.
 2010 Microchip Technology Inc.
13.1.4
LINK CHANGE
The link change interrupt occurs when the PHY link
status changes. This flag is set by hardware when a link
has either been established or broken between the
device and a remote Ethernet partner. The current link
status can be read from PHYLNK (ESTAT<8>). The
interrupt should be cleared by software once it has
been serviced.
To enable the link change interrupt, set LINKIE
(EIE<11>).
13.1.5
RECEIVED PACKET PENDING
The received packet pending interrupt occurs when
one or more frames have been received and are ready
for software processing. This flag is set when the
PKTCNT<7:0> (ESTAT<7:0>) bits are non-zero. This
interrupt flag is read-only and will automatically clear
when the PKTCNT bits are decremented to zero. For
more details about receiving and processing incoming
frames, refer to Section 9.0 “Transmitting and
Receiving Packets”.
To enable the received packet pending interrupt, set
PKTIE (EIE<6>). The corresponding interrupt flag is
PKTIF (EIR<6>).
13.1.6
DMA COMPLETE
The DMA complete interrupt occurs when a DMA operation (either copy or checksum calculation) completes.
This flag is set when DMAST (ECON1<5>) is cleared.
The interrupt should be cleared by software once it has
been serviced.
To enable the DMA complete interrupt, set DMAIE
(EIE<5>).
13.1.7
TRANSMIT COMPLETE
The transmit complete interrupt occurs when the transmission of a frame has ended (whether or not it was
successful). This flag is set when TXRTS (ECON1<1>)
is cleared. The interrupt should be cleared by software
once it has been serviced.
To enable the transmit complete interrupt, set TXIE
(EIE<3>).
DS39935C-page 121
ENC424J600/624J600
13.1.8
TRANSMIT ABORT
The transmit abort interrupt occurs when the transmission of a frame has been aborted. An abort can occur
for any of the following reasons:
• Excessive collisions occurred as defined by the
Retransmission Maximum, MAXRET<3:0> bits
(MACLCON<3:0>), setting. If this occurs, the
COLCNT bits (ETXSTAT<3:0>) will indicate the
number of collisions that occurred.
• A late collision occurred after 63 bytes were transmitted. If this occurs, LATECOL (ETXSTAT<10>)
will be set.
• The medium was busy and the packet was
deferred. If this occurs, EXDEFER (ETXSTAT<8>)
will be set.
• The application aborted the transmission by
clearing TXRTS (ECON1<1>).
The interrupt should be cleared by software once it has
been serviced.
To enable the transmit abort interrupt, set TXABTIE
(EIE<2>).
13.1.9
RECEIVE ABORT
The receive abort interrupt occurs when the reception
of a frame has been aborted. A frame being received is
aborted when the Head Pointer attempts to overrun the
Tail Pointer, or when the packet counter has reached
FFh. In either case, the receive buffer is full and cannot
fit the incoming frame, so the packet has been
dropped. This interrupt does not occur when packets
are dropped due to the receive filters rejecting a
packet. The interrupt should be cleared by software
once it has been serviced.
13.2
Wake-on-LAN/Remote Wake-up
Wake-on-LAN or remote wake-up is useful for conserving system power. The host controller and other
subsystems can be placed in Low-Power mode, then
configured to wake-up when a Magic Packet™ is
received by the ENC424J600/624J600 devices.
For Wake-on-LAN to operate correctly, the device must
not be in Low-Power mode and the receive module
must be enabled. When a Magic Packet arrives, the
device wakes the host controller via the INT signal.
To configure the device for Wake-on-LAN:
1.
2.
3.
4.
5.
Set the host controller to wake-up on an external
interrupt signal from INT.
Set CRCEN (ERXFCON<6>), RUNTEN
(ERXFCON<4>) and MPEN (ERXFCON<14>).
Clear all other filter enable bits. This configures
the device to only accept Magic Packets.
Service all pending packets.
Set PKTIE (EIE<6>) and INTIE (EIE<15>) to
interrupt when a packet is accepted.
Put the host controller and other subsystems to
Sleep to save power.
Once a Magic Packet is received, PKTCNT is incremented to ‘1’, causing the device to assert the interrupt
signal. When the host wakes up, it needs to restore the
normal filter configuration and continue performing its
tasks.
For more details about the Magic Packet filter, refer to
Section 10.10 “Magic Packet™ Collection Filter”.
To enable the receive abort interrupt, set RXABTIE
(EIE<1>). The corresponding interrupt flag is RXABTIF
(EIR<1>).
13.1.10
RECEIVE PACKET COUNTER FULL
The receive packet counter full interrupt occurs when
the PKTCNT (ESTAT<7:0>) bits have reached FFh.
This indicates that the counter for received frames is
full and no more packets can be received. If a packet
arrives after this flag is set, it will cause the receive
abort interrupt flag to be set. This flag is cleared by
hardware once the PKTCNT bits are decremented.
To enable the receive packet counter full interrupt, set
PCFULIE (EIE<0>).
DS39935C-page 122
 2010 Microchip Technology Inc.
ENC424J600/624J600
14.0
DIRECT MEMORY ACCESS
(DMA) CONTROLLER
ENC424J600/624J600 devices incorporate a Direct
Memory Access (DMA) controller to reduce the burden
on the host processor. The module serves the following
purposes:
• Copying data from one part of the packet buffer to
another.
• Copying data between the packet buffer and one
of the memory mapped cryptographic engines.
• Calculating a 16-bit checksum over a block of
data, compatible with the checksum used in
standard protocols, such as IP and TCP.
It is recommended that DMA configuration parameters
(such as address pointers and operation selection bits)
not be modified while DMAST (ECON1<5>) is set and
the DMA is active. This requirement is additionally true
for the EUDAND Pointer, even if it is not located anywhere within the source or destination memory ranges
of the DMA. After processing each memory word, the
DMA performs the necessary address wrap-around
checks to increment to the next address(es). If the host
controller writes to EUDAND at the exact moment the
DMA is performing an address wrap-around check, it is
possible that the EUDAND register will be in a
temporary incoherent state and the DMA source or
destination address will wrap to the EUDAST value
unintentionally.
In general, the application configures the DMA operation parameters (such as source and destination
addresses), then sets the DMAST (ECON1<5>) bit to
start the transfer or calculation. The hardware automatically clears the bit when the operation finishes.
Additionally, the module can be configured to set an
interrupt flag on completion, as detailed in
Section 13.0 “Interrupts”.
Depending upon the operation and the alignment of the
source and destination addresses, the DMA module
typically requires between one and three clock cycles
of OSC1 per 16-bit word. Any DMA operation in
progress can be cancelled by clearing the DMAST bit.
The DMA module follows the same address
wrap-around logic as the indirect memory access
interfaces described in Section 3.5.5 “Indirect SRAM
Buffer Access”. When a read or write operation
reaches the end of the User-Defined Area (UDA)
specified by
EUDAND, it automatically wraps to
EUDAST. When an operation reaches the end of the
general purpose buffer, as indicated by ERXST – 1, it
automatically wraps to 0000h. Finally, when an operation reaches the end of the receive buffer (the last
address in the physical memory space), it automatically
wraps to ERXST. If any of these areas share an ending
address, the UDA wrapping will take priority, followed
by the general purpose buffer wrapping, then the
receive buffer. The wrap-around applies to both the
source and destination addresses as an operation
progresses.
The DMA can copy any length of data from any address
to any destination, including the corner case when the
length is zero. Source and destination addresses may
be within the implemented SRAM area (0000h through
5FFFh) or the cryptographic data area (7800h through
7C4Fh). It is not possible to use the DMA to read or
write from SFRs.
Although memory is organized by the 16-bit word, the
DMA accepts any byte address as the source and
destination. It is also capable of operation over an even
or an odd number of bytes. Internally, the DMA uses
16-bit accesses, so optimal efficiency is achieved when
both the source and destination addresses are even, or
when both are odd. Copy operations from an odd
source address to an even destination address or vice
versa are allowed; however, performance will be diminished by approximately 50% relative to copy operation
on addresses that are aligned to each other.
 2010 Microchip Technology Inc.
14.1
Copying Memory
Before initiating the first copy operation, verify that the
ETHEN (ECON2<15>) and CLKRDY (ESTAT<12>)
bits are set. This does not need to be done for
subsequent operations.
To copy data from one location to another:
1.
2.
3.
4.
5.
6.
7.
8.
9.
Verify that the values of ERXST, EUDAND and
EUDAST (if applicable) are selecting the
desired buffer wrapping configuration.
Verify that DMAST (ECON1<5>) is clear,
indicating that the module is Idle.
Set DMACPY (ECON1<4>) to select a copy
operation.
Optionally, set DMANOCS (ECON1<2>) to
prevent a checksum calculation.
Set EDMAST to point to the source address.
Set EDMADST to point to the destination
address.
Set EDMALEN to indicate the number of bytes
to copy.
Set DMAST to initiate the operation.
Wait for the hardware to clear DMAST to indicate
completion. If the DMA interrupt is enabled, it will
be triggered when DMAST is cleared.
DS39935C-page 123
ENC424J600/624J600
Copy operations are performed starting with the first
byte or word at the source address and incrementing
forward. It is legal to use the DMA to move a block of
data backwards in memory, even if the source and
destination memory ranges overlap. For example, if a
65-byte packet of data was located starting at memory
address 0001h, and the application wished to move the
whole packet to address 0000h, it may simply program
EDMAST to 0001h and EDMADST to 0000h. The
non-overlapping byte at address 00041h will remain
unchanged. Similarly, it is also legal to move a block of
data from an even aligned address to an immediately
prior odd aligned address. For example, moving from
0002h to 0001h will work correctly with the final
non-overlapping byte again remaining unchanged.
Since copy operations start at the beginning of the
source address range and increment forward (as
opposed to starting at the end of the source range and
incrementing backwards), it is not possible to move
blocks of data forward towards a higher memory
address if the source and destination address ranges
overlap. To perform this operation, the application must
copy the source data to a non-overlapping temporary
buffer location and then copy it from the temporary
buffer to the final destination.
14.2
Checksum Calculations
The DMA module can compute an IP checksum value
over a given range of bytes. Checksums can be calculated over a specific range of memory, or simultaneously
as a copy operation progresses. Remember to verify
that the values of ERXST, EUDAND and EUDAST (if
applicable) are selecting the desired buffer wrapping
configuration before starting any checksum operation.
The checksum calculation logic treats the source data
as a series of 16-bit big-endian integers. If the source
data has an odd number of bytes, a padding byte of 00h
will be added for the calculation. (This byte is not
copied to the destination if the checksum is part of a
copy operation.) The calculated checksum is the 16-bit
one’s complement of the one’s complement sum of all
16-bit integers in the series. For example, if the bytes
included in the checksum were {89h, ABh, CDh}, the
checksum would begin by calculating 89ABh + CD00h.
A carry would occur and the result would be 56ACh.
That value would be complemented to yield a
checksum of A953h.
To calculate a checksum without copying data:
1.
2.
3.
4.
5.
Verify that DMAST (ECON1<5>) is clear,
indicating that the module is Idle.
Clear DMACPY (ECON1<4>) to prevent a copy
operation.
Clear DMANOCS (ECON1<2>) to select a
checksum calculation.
Clear DMACSSD (ECON1<3>) to use the
default seed of 0000h. See the paragraph below
to seed a checksum with another value.
Set EDMAST to point to the source address.
DS39935C-page 124
6.
7.
8.
9.
Set EDMALEN to indicate the length of the input
data.
Set DMAST to initiate the operation.
Wait for the hardware to clear DMAST to indicate
completion. If the DMA interrupt is enabled, it will
be triggered when DMAST is cleared.
Read the computed checksum from EDMACS.
To calculate a checksum while copying data:
1.
Verify that DMAST is clear, indicating that the
module is Idle.
2. Set DMACPY to select a copy operation.
3. Clear DMANOCS to select a checksum
calculation.
4. Clear DMACSSD to use the default seed of
0000h. See the paragraph below to seed a
checksum with another value.
5. Set EDMAST to point to the source address.
6. Set EDMADST to point to the destination
address.
7. Set EDMALEN to indicate the number of bytes
to copy.
8. Set DMAST to initiate the operation.
9. Wait for the hardware to clear DMAST to indicate
completion. If the DMA interrupt is enabled, it will
be triggered when DMAST is cleared.
10. Read the computed checksum from EDMACS.
The checksum can be seeded with a previous value if
required. Seeding may be useful when attempting to
compute a checksum over non-contiguous blocks of
data. To seed the checksum, set DMACSSD
(ECON1<3>) before initiating the operation. The
checksum calculation is seeded with the one’s
complement of the value contained in EDMACS prior to
the start of the DMA operation.
14.3
DMA Performance
The DMA controller can operate at any time, without
any regard to other modules in the device. Several
factors affect its speed of operation, including:
• Ethernet transmit and receive utilization,
especially at 100 Mbps
• SPI or PSP read or write operations to the SRAM
• Operating mode (copy versus checksum only)
• Even-to-odd or odd-to-even source and
destination addresses (Copy mode)
Neglecting the time it takes software to program the
DMA control SFRs, under typical unloaded conditions,
the DMA will have a Checksum Only mode throughput
of 100 Mbytes/second. Copy mode (with or without
checksum) will achieve a typical throughput of
50 Mbytes/second when the source and destination
addresses share the same alignment. Differing source
and destination alignment would slow the process to
33.3 Mbytes/second.
Worst case conditions can cut the DMA throughput by
no more than half of the typical values.
 2010 Microchip Technology Inc.
ENC424J600/624J600
15.0
CRYPTOGRAPHIC SECURITY
ENGINES
To reduce the processing requirements of the host
controller, ENC424J600/624J600 devices incorporate
three different cryptographic security engines. These
security engines perform the types of encryptions,
decryptions and mathematical computations that are
most commonly used for network security functions.
They accelerate the computation of public/private key
pair negotiations, message hash authentication and
bulk data encryption.
The engines implemented are:
• Modular Exponentiation
• MD5 and SHA-1 Hashing
• Advanced Encryption Standard (AES)
Each engine operates from the cryptography data
memory area, shown in Section 3.4 “Cryptographic
Data Memory”. This memory block is not directly accessible through the SPI or PSP interfaces. Instead, data
must be copied into this memory area using the DMA, as
described in Section 14.1 “Copying Memory”.
The modules are controlled using bits from the ECON2,
ECON1 and EIR registers (Registers 8-1, 9-1 and 13-1,
respectively). Each of the three modules have separate
resources, so they may all be active simultaneously if
necessary. Each module also has its own interrupt that
can be enabled to signal completion. Refer to
Section 13.0 “Interrupts” for details on using interrupts.
All of the cryptographic security engines require that the
Ethernet enable bit, ETHEN (ECON2<15>) to be set for
operation. However, the PHY, which consumes the
majority of the device current, can be put to sleep if the
application wishes to perform cryptographic operations
without Ethernet connectivity. The PHY sleep function is
controlled by the PSLEEP bit (PHCON1<11>). For
greater information on power down capabilities, refer to
16.0 “Power-Saving Features”. As a unit, the Modular
Exponentiation and AES engines can be disabled to
reduce the device’s power consumption. This feature is
controlled by the CRYPTEN bit (EIR<15>). To enable
Modular Exponentiation and AES engines, set
CRYPTEN. By default, CRYPTEN is cleared and the
modules are disabled on device power-up. The
MD5/SHA-1 hashing module remains available
regardless of the CRYPTEN state.
 2010 Microchip Technology Inc.
15.1
Modular Exponentiation
Modular Exponentiation is the base function for the
RSA and Diffie-Hellman algorithms used in public key
cryptography. This module computes the value, Y = XE
mod M, where 0  X, Y< M and E > 0 and 2N-1  M < 2N.
N is the chosen operand size of 512, 768 or 1024.
The Modular Exponentiation engine is controlled by the
MODEXST bit (ECON1<15>). Setting this bit initiates
the calculation. The engine automatically clears the bit
when the operation is complete. Clearing the bit in software aborts the calculation in progress and leaves the
calculated value in an indeterminate state.
The engine supports operand lengths of 512, 768 or
1024 bits. Operand size is selected with the
MODLEN<1:0> bits (ECON2<3:2>). The modulus M
and base X can be any value up to the maximum value
supported by the chosen operand length. However, if
X ≥ M, the result is not ensured to be correct. Additionally, incorrect results will occur if the exponent E is 0
(this would return the same value as E = 1). Shorter
exponents may commonly be used when performing
RSA encryption, which typically uses a 17-bit exponent
length, or Diffie Hellman computations using a 180-bit
exponent.
For the Modular Exponentiation engine to work
correctly, the Most Significant (MSb) bit of M must be
set. For example, when the MODLEN bits are configured for 1024-bit operation, M must be set such that
21023 ≤ M < 21024. In other words, the modulus must
exactly match the chosen operand length of 512 bits,
768 bits or 1024 bits. Although it usually is, the modulus
does not have to be a prime number.
All operands must be stored in network (big-endian)
byte order. If the base X or exponent E operands are
shorter than the selected operand length, they should
be right-justified and left-padded with zeros out to the
chosen operand length.
DS39935C-page 125
ENC424J600/624J600
To perform a modular exponentiation:
Copy the values for X, E and M into the 24-Kbyte
SRAM.
2. Set CRYPTEN (EIR<15>) to turn on the Modular
Exponentiation module.
3. Use the DMA to transfer E to addresses, 7800h
through 783Fh (512-bit), 785F (768-bit) or
787Fh (1024-bit). If the value is shorter than the
chosen operand length, left-pad the value with
zeros.
4. Use the DMA to transfer the value of X to
addresses, 7880h through 78BFh (512-bit),
78DF (768-bit) or 78FFh (1024-bit). If the value
is shorter than the chosen operand length,
left-pad the value with zeros.
5. Use the DMA to transfer M to addresses, 7900h
through 793Fh (512-bit), 795F (768-bit) or
797Fh (1024-bit). The value must not be shorter
than the chosen operand length.
6. Set the value of the MODLEN<1:0>
(ECON2<3:2>) bits to indicate the size of the
operation to be completed.
7. Set MODEXST (ECON1<15> = 1) to initiate the
calculation.
8. Wait for the hardware to clear MODEXST to
indicate that the operation has completed. The
hardware will also set MODEXIF (EIR<14>) and
generate an interrupt, if enabled.
9. Use the DMA to transfer the result Y from
addresses, 7880h through 78BFh (512-bit), 78DF
(768-bit) or 78FFh (1024-bit). Note that this result
will be in big-endian format, and if necessary, the
result will be left-padded with zeros.
10. If the AES module is not in use, save power by
clearing CRYPTEN. Use a Bit Field Clear SPI
instruction or write to the EIRCLR register to
clear this bit without corrupting any interrupt
flags.
15.1.1
MODULAR EXPONENTIATION
PERFORMANCE
1.
Assuming the operating length remains constant, the
exponent E and modulus M are retained within the
Modular Exponentiation engine and can be reused for
future operations without being reloaded.
DS39935C-page 126
The time required to compute the Modular
Exponentiation result depends on three factors:
• the “active” length of the exponent E.
• the density of ‘1’ bits in the exponent E.
• the length of the operands
The time required for typical operations is summarized
in Table 15-1.
TABLE 15-1:
TYPICAL MODULAR
EXPONENTIATION
PERFORMANCE
Operands
(M/E)
Time
DH
768/180
50.2 ms
DH
1024/180
89.0 ms
RSA
512/512
63.7 ms
Usage
RSA
768/768
214.0 ms
RSA
1024/1024
506.2 ms
15.2
MD5 and SHA-1 Hashing
The MD5 and SHA-1 hash engines implement one-way
message digest functions. These functions take an
unlimited amount of data and produce a digest of either
128 or 160 bits (for MD5 and SHA-1, respectively). They
are frequently used for verification and integrity
purposes.
Both hashing engines share the same resources, so
only one operation may be active at a time. The current
operation is selected by the SHA1MD5 (ECON2<12>)
bit. This bit should be configured before using the
module. Context switching is supported by the engine
for applications that require the capability to switch
between two or more hashing operations.
The HASHOP (ECON1<13>) bit configures the initialization values. When starting a new hash calculation,
clear this bit to reset the initialization values. Using this
bit to load a previously saved context is described in
Section 15.2.3 “Context Switching”. The value of the
HASHOP bit may not be changed once the HASHEN
bit is set, so it must be configured first.
 2010 Microchip Technology Inc.
ENC424J600/624J600
Set the HASHEN (ECON1<14>) bit to enable the
module and begin transferring data. Once this bit is set,
all data copied to the module through the DMA will be
added to the hash calculation. Data should be written
beginning at the Hash Data In address, 7A00h. After
copying 64 bytes, the application must pause and wait
for the HASHIF (EIR<13>) bit to be set by the
hardware. This flag indicates that the hardware has
completed processing for that block. The application
should then clear the HASHIF flag and continue with
the next block, beginning transfers again at address
7A00h.
Before the final DMA transfer is started, the application
must set the HASHLST bit (ECON1<12>). When this
bit is set, and a DMA transfer is initiated to the hash
engine, the engine pads the input appropriately for the
selected algorithm and calculates the final result. Once
the HASHIF flag is set, the message digest is available
in Digest/State Out, beginning at address 7A70h.
The application must wait for the HASHIF flag after every
64-byte block, but all 64 bytes need not be transferred in
one operation. For example, it is possible to transfer
16 bytes in one operation and the remaining 48 in a second. However, it is required that the DMA stop copying
data once a full 64-byte block is created. For example, if
16 bytes are transferred in one operation, and 52 in the
next (for a total of 68 bytes), then the final four bytes will
be lost and the output will be incorrect.
Note that the Hash Data In memory is not physically
implemented, nor is it accessible for reading. Transfers
to any address in the range of 7A00h to 7A3Fh instruct
the DMA to write directly to the hash engine. Therefore,
if 32 bytes are copied, beginning at 7A00h, a subsequent write of 32 bytes to the same address will not
overwrite the previously written data. Instead, the two
32-byte writes are appended to form a single 64-byte
block and the hashing process begins. When making
multiple transfers as part of a single 64-byte block, the
second and subsequent transfers may begin, either at
their sequential location, or they may all use the same
destination address of 7A00h.
With the exception of the final transfer, all data transfers
to the hash engine must be of an integral length of
4 bytes. For example, chunks of 4, 8, 12, 16, etc. are
legal, while DMA transfers of length 1, 2, 3, 5, 6, 7, 9,
10, 11, etc. are illegal. Optimal DMA copy performance
is also achieved when the source address is word or
even aligned. To allow for hashes to be computed over
any length of data, the integral length of 4 restriction
does not apply to the last transfer (when HASHLST is
set).
 2010 Microchip Technology Inc.
15.2.1
MD5 HASHING
The module implements the MD5 function, as
described in the Internet Engineering Task Force
RFC 1321, “The MD5 Message Digest Algorithm”. The
resulting digest is 128 bits (16 bytes) in length and is
left-justified in the result space.
To calculate an MD5 digest:
1.
Clear SHA1MD5 (ECON2<12>), HASHOP
(ECON1<13>) and HASHLST (ECON1<12>).
2. Set HASHEN (ECON1<14>).
3. Clear HASHIF (EIR<13>).
4. Use the DMA to transfer exactly 64 bytes to
address 7A00h. This transfer may be split into
multiple transactions if each copy operation is
an integral length of 4 and the net of all transfers
is 64 bytes.
5. Wait for HASHIF to be set.
6. Repeat steps 3 through 5 until fewer than
64 bytes remain.
7. Clear HASHIF.
8. Set HASHLST (ECON1<12>).
9. Use the DMA to transfer the remaining bytes to
address 7A00h.
10. Wait for HASHIF to be set.
11. Use the DMA to transfer the resulting 16-byte
hash from address 7A70h. This 128-bit hash will
be in big-endian byte order.
12. Clear HASHEN.
Step 5 will take 500 ns from the time the DMA completes the transfer. Under worst case conditions, the
DMA will take 3.94 s to copy a block of 64 bytes after
the DMAST bit is set. Therefore, for maximum performance, applications may choose to omit step 3 and
replace step 5 with a processor enforced wait of at least
4.5 s between the start of a DMA copy operation and
the start of the next DMA copy operation of 64 bytes.
Steps 7 and 10 may also be optimized. However, the
wait period should be extended to no less than 5.6 s
as the hardware requires extra time to perform an extra
padding step as required by the MD5 algorithm.
Step 9 can be split into multiple DMA copy transactions
if step 8 is held off until immediately before the very last
DMA copy operation is performed.
DS39935C-page 127
ENC424J600/624J600
15.2.2
SHA-1 HASHING
The module implements the SHA-1 function as
described in the NIST Federal Information Processing
Standard (FIPS) Publication 180-1. The resulting digest
is 160 bits (20 bytes) in length.
To calculate a SHA-1 digest:
1.
Set SHA1MD5 (ECON2<12>). Clear HASHOP
and HASHLST (ECON1<13:12>).
2. Set HASHEN (ECON1<14>).
3. Clear HASHIF (EIR<13>).
4. Use the DMA to transfer exactly 64 bytes to
address 7A00h. This transfer may be split into
multiple transactions if each copy operation is
an integral length of 4 and the net of all transfers
is 64 bytes.
5. Wait for HASHIF to be set.
6. Repeat steps 3 through 5 until fewer than
64 bytes remain.
7. Clear HASHIF.
8. Set HASHLST (ECON1<12>).
9. Use the DMA to transfer the remaining bytes to
address 7A00h.
10. Wait for HASHIF to be set.
11. Use the DMA to transfer the resulting 20-byte
hash from address 7A70h. This 160-bit hash will
be in big-endian byte order.
12. Clear HASHEN.
Like the MD5 hashing case, steps 3, 5, 7 and 10 can be
optimized by replacing them with enforced wait
periods. However, SHA-1 is slightly slower than MD5
so a wait period of at least 4.7 s should be used in
place of step 5 and at least 5.8 s for step 10.
15.2.3
CONTEXT SWITCHING
At each 64-byte boundary, the current output state can
be read from the module. This output state can be
stored in memory elsewhere, then loaded back into the
module at a later time to continue the hash. Using this
feature allows the engine to alternate between
calculating two or more digests simultaneously.
To make use of the context switching capability:
1.
2.
3.
4.
Initiate a hash calculation.
After hashing an integral number of 64-byte
blocks, wait for the HASHIF flag to be set.
Read the current context from the module and
store it elsewhere in memory. The context
includes the Digest/State Out and Length State
Out values, which comprise the 28 bytes starting
at address 7A70h.
Once the context has been saved, clear the
HASHEN (ECON1<14>) bit to disable the
module. The module is now available to be used
by other operations.
When the application is ready to resume the previous
calculation, restore the context to the Initialization
Vector/State In and Length State In values, beginning
at 7A40h. Then, set the HASHOP (ECON1<13>) bit to
indicate that a previous state is to be loaded from
memory rather than initializing a new calculation. Once
this bit is set, setting the HASHEN bit allows the hash
operation to proceed as usual.
After the context has been saved, the module may be
used for a different type of hash (MD5 instead of
SHA-1, or vice versa). When loading a context back
into the module, verify that SHA1MD5 (ECON2<12>)
selects the correct hash operation.
Also, like the MD5 case, step 9 can be split into multiple
DMA copy transactions if step 8 is held off until immediately before the very last DMA copy operation is
performed.
DS39935C-page 128
 2010 Microchip Technology Inc.
ENC424J600/624J600
To switch the context during a calculation:
15.2.4
1.
The implications noted in Section 15.2.1 “MD5 Hashing” and Section 15.2.2 “SHA-1 Hashing” are that
the hashing engine is extremely fast and net throughput is primarily limited by the DMA. Using an open-loop
method of skipping DMA and hash status checking, it is
possible to attain a net hashing throughput of
13.6 Mbytes/second (108 Mbits/second). Practical
considerations, such as the time it takes to send and
receive the data between the Ethernet and host
microcontroller, will generally play a bigger roll in the
total application performance.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
Configure SHA1MD5 (ECON2<12>) to select
the correct operation.
Clear HASHOP (ECON1<13>) to begin a new
hash.
Set HASHEN (ECON1<14>).
Clear HASHIF (EIR<13>).
Use the DMA to transfer exactly 64 bytes to
address 7A00h. This transfer may be split into
multiple transactions if each copy operation is
an integral length of 4 and the net of all transfers
is 64 bytes.
Wait for HASHIF to be set.
Repeat steps 4 through 6 for as many complete
64-byte blocks as are ready to be hashed.
Use the DMA to transfer the resulting 28 bytes
of context data, beginning at address 7A70h, to
another location in memory.
Clear HASHEN.
Use the module for other operations as
necessary.
Configure SHA1MD5 as in step 1.
Use the DMA to transfer the 28 bytes of stored
context to address 7A40h.
Set HASHOP and HASHEN to resume a
previous calculation.
Continue using the module as previously
described by hashing more data, then either
saving the state or completing the calculation.
It is important to note that the Digest/State Out only
contains either a Digest or a State Out initialization vector, but not both. If the HASHLST bit is set before the
final DMA transfer, the value will indicate the final
digest of all data processed so far. This digest is not a
valid initialization vector and cannot be used to resume
the hash. This is true even if the final transfer filled the
buffer to a 64-byte boundary. Likewise, if HASHLST is
clear before the final DMA transfer, the value can only
be used as an initialization vector. It will not be a valid
hash of the message so far. Therefore, applications
that require the capability to calculate a hash, add more
data and continue, should buffer up to 64 bytes in
memory. Only perform the hash operation on a block
once the 65th byte is ready to be hashed. This allows
the application to select whether a Digest or a State Out
initialization vector is desired before hashing a block.
Provided the context is stored, the application could
request a digest, then reload the context and retransfer
the data (beginning at the most recent 64-byte
boundary) to continue the hashing operation where it
was last stopped.
 2010 Microchip Technology Inc.
15.3
MD5/SHA-1 HASH PERFORMANCE
Advanced Encryption Standard
(AES)
The AES engine implements the Advanced Encryption
Standard (originally known as Rijndael), as described
in the NIST Federal Information Processing Standard
Publication 197. This module can be used to encrypt or
decrypt data using a known secret key. Context
switching is supported for applications that require the
capability to alternate between two or more operations
or keys.
AES is a block cipher that must operate over 128-bit
(16-byte) blocks. The application must apply any
necessary padding, or strip any extraneous output
bytes, as dictated by the desired padding scheme. No
support for padding is included in the engine.
15.3.1
KEY SUPPORT
The AES engine supports 128, 192 and 256-bit key
sizes. Keys for AES are symmetric, meaning both parties
must agree on a shared secret before the algorithm can
be used. This is typically accomplished using an asymmetric algorithm, such as RSA, and/or is handled by a
higher level protocol, such as Secure Socket Layer (SSL)
or Transport Layer Security (TLS).
To load an encryption key:
1.
2.
3.
Verify that AESST (ECON1<11>) is clear,
indicating that the engine is Idle.
Configure AESLEN<1:0> (ECON2<1:0>) to
select the correct key size.
Use the DMA to transfer the key data to address
7C00h. Keys shorter than 256 bits should be
left-aligned.
AES generates a series of roundkeys from the encryption key using an expansion function. While encryption
begins at the first of these keys, decryption must start
from the last one. The AES module includes a key
expander, which calculates the roundkeys as needed
by the encryption engine. To calculate the last roundkey before beginning decryption, the engine must first
be operated in Encryption mode for one block.
DS39935C-page 129
ENC424J600/624J600
To initialize decryption using a known encryption key:
15.3.3
1.
Block ciphers are commonly used in one of five modes
as described by the NIST Special Publication 800-38A,
“Recommendations for Block Cipher Modes of
Operation: Methods and Techniques”. The use of the
AES engine in each of these modes is described in the
following sections.
2.
3.
4.
5.
6.
Verify that AESST is clear, indicating that the
engine is Idle.
Configure AESLEN<1:0> to select the correct
key size.
Use the DMA to transfer the encryption key to
address 7C00h. Keys shorter than 256 bits
should be left-aligned.
Configure AESOP<1:0> (ECON1<10:9>) to
‘00’.
Set AESST to initiate the key expansion.
Wait until the hardware clears the AESST flag.
15.3.2
CONTEXT SWITCHING
After each block is complete, the internal state may be
saved in order to switch encryption keys or operations.
Context switching may only be performed when
AESST (ECON2<11>) is clear, indicating that the
engine is Idle. The values comprising the context varies
depending on the mode selected. The sections
describing each mode details which values must be
saved.
FIGURE 15-1:
BLOCK MODES
Four modes are natively supported in hardware:
•
•
•
•
Electronic Code Book (ECB)
Cipher Block Chaining (CBC)
Cipher Feedback (CFB)
Output Feedback (OFB)
The fifth mode, Counter (CTR), can be used with the
addition of software support for the counter.
15.3.3.1
ECB ENCRYPTION AND DECRYPTION
DECRYPTION
ENCRYPTION
Plaintext1
Plaintext0
KEY
Ciphertext0
Key
Key
DATA
Electronic Code Book Mode (ECB)
The Electronic Code Book mode applies the AES
encryption function directly to each plaintext block. No
feedback is included, so the encryption of each block is
completely independent of any previous block.
Assuming a given session key, any plaintext block will
always yield to the same ciphertext block (and vice
versa). If this is an undesirable property, a different
block mode should be selected. Figure 15-1 shows the
use of ECB mode for encryption and decryption.
DATA
KEY
Ciphertext1
Key
DATA
KEY
Key
DATA
KEY
ENCRYPTER
ENCRYPTER
DECRYPTER
DECRYPTER
Ciphertext0
Ciphertext1
Plaintext0
Plaintext1
DS39935C-page 130
 2010 Microchip Technology Inc.
ENC424J600/624J600
To encrypt a block using ECB mode:
1.
2.
3.
4.
5.
6.
7.
Load the encryption key as described in
Section 15.3.1 “Key Support”.
Set AESOP<1:0> (ECON1<10:9>) to ‘00’.
Copy the plaintext message to TEXTA at 7C20h.
Set AESST (ECON1<11>) to initiate the
encryption.
Wait for the hardware to clear AESST.
Read the ciphertext message from TEXTA at
7C20h.
Repeat steps 3 through 6 for subsequent blocks.
To decrypt a block using ECB mode:
1.
2.
3.
4.
Initialize the decryption key as described in
Section 15.3.1 “Key Support”.
Set AESOP<1:0> to ‘10’.
Copy the ciphertext message to TEXTA at
7C20h.
Set AESST to initiate the decryption.
FIGURE 15-2:
5.
6.
7.
Wait for the hardware to clear AESST.
Read the plaintext message from TEXTA at
7C20h.
Repeat steps 3 through 6 for subsequent blocks.
The context for ECB mode includes only the encryption
key. No additional context data needs to be saved.
15.3.3.2
Cipher Block Chaining Mode (CBC)
The Cipher Block Chaining mode uses feedback from
the encryption output to further obscure the ciphertext
data. During encryption, the first block uses an Initialization Vector (IV) which is XORed with the plaintext
data. The output of this XOR function is then encrypted
using the AES key and this ciphertext becomes the IV
for the next block. Under CBC mode, each subsequent
block depends on the previous block. Therefore,
identical subsequent plaintext blocks use a different IV,
and therefore, yield different ciphertext blocks.
Figure 15-2 shows the use of CBC mode for encryption
and decryption.
CBC ENCRYPTION AND DECRYPTION
DECRYPTION
ENCRYPTION
Plaintext0
Plaintext0
Key
Key
IV
Key
DATA
KEY
ENCRYPTER
KEY
Key
DATA
Ciphertext1
Ciphertext0
DATA
KEY
DATA
DECRYPTER
DECRYPTER
Plaintext0
Plaintext1
KEY
ENCRYPTER
IV
Ciphertext0
 2010 Microchip Technology Inc.
Ciphertext1
DS39935C-page 131
ENC424J600/624J600
To encrypt a block using CBC mode:
1.
2.
3.
4.
5.
6.
7.
8.
8.
Load the encryption key as described in
Section 15.3.1 “Key Support”.
Set AESOP<1:0> (ECON1<10:9>) to ‘01’.
Copy the Initialization Value (IV) to TEXTA at
7C20h.
Copy the plaintext message to TEXTB at
7C30h.
Set AESST (ECON1<11>) to initiate the
encryption.
Wait for the hardware to clear AESST.
Read the ciphertext message from TEXTA at
7C20h.
Repeat steps 4-7 for subsequent blocks. The
ciphertext from the previous block automatically
becomes the IV for the following block.
To decrypt a block using CBC mode:
1.
2.
3.
4.
5.
6.
7.
Initialize the decryption key as described
Section 15.3.1 “Key Support”.
Set AESOP<1:0> to ‘10’.
Copy the Initialization Value (IV) to TEXTB
7C30h.
Copy the ciphertext message to TEXTA
7C20h.
Set AESST to initiate the decyption.
Wait for the hardware to clear AESST.
Read the plaintext message from XOROUT
7C40h.
FIGURE 15-3:
in
at
at
9.
If another block is to be decrypted, copy the
ciphertext message from this block to TEXTB at
7C30h. The ciphertext from this block becomes
the IV for the following one.
Repeat steps 4-8 for subsequent blocks.
The context for CBC mode consists of both the AES
encryption key and the ciphertext from the most recent
block. Save the ciphertext from the previous block to be
used as the IV when resuming the operation for
additional blocks.
15.3.3.3
Cipher Feedback Mode (CFB)
Cipher Feedback mode is similar to CBC in that the
ciphertext becomes the Initialization Vector (IV) for the
subsequent block. However, in CFB mode, only the IV
is encrypted, then XORed with the plaintext to form the
ciphertext. For the second and subsequent blocks, the
ciphertext is passed through the encryption function
again, then XORed with the next plaintext block to
become the ciphertext. Like CBC mode, each
subsequent block depends on the previous block.
Therefore, identical subsequent plaintext blocks will
use a different IV, and therefore, yield different ciphertext blocks. Figure 15-3 shows the use of CFB mode
for encryption and decryption.
Note:
at
Only 128-bit CFB mode is natively
supported. Other less common implementations, including 1-bit and 8-bit CFB
modes, could be accomplished with
support software, but are not detailed here.
CFB ENCRYPTION AND DECRYPTION
ENCRYPTION
IV
Key
DATA
KEY
DECRYPTION
DATA
Key
IV
Key
KEY
DATA
KEY
ENCRYPTER
ENCRYPTER
Plaintext0
Plaintext1
Ciphertext0
DS39935C-page 132
Ciphertext1
Key
DATA
ENCRYPTER
ENCRYPTER
Ciphertext0
Plaintext0
KEY
Ciphertext1
Plaintext1
 2010 Microchip Technology Inc.
ENC424J600/624J600
To encrypt a block using CFB mode:
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
3.
Load the encryption key as described in
Section 15.3.1 “Key Support”.
Set AESOP<1:0> (ECON1<10:9>) to ‘00’.
Copy the Initialization Value (IV) to TEXTA at
7C20h.
Set AESST (ECON1<11>) to initiate the
encryption.
Copy the plaintext message to TEXTB at 7C30h.
Wait for the hardware to clear AESST.
Read the ciphertext message from XOROUT at
7C40h.
If more blocks need to be encrypted, set
AESOP<1:0> to ‘01’. This causes the engine to
read from XOROUT rather than TEXTA.
Set AESST to initiate the encryption.
Copy the plaintext message to TEXTB at 7C30h.
Wait for the hardware to clear AESST.
Read the ciphertext message from XOROUT at
7C40h.
Repeat steps 9 through 12 for subsequent
blocks. The ciphertext from the previous block
automatically becomes the IV for the following
block.
To decrypt a single block using CFB mode:
1.
2.
Load the encryption key as described in
Section 15.3.1 “Key Support”.
Set AESOP<1:0> to ‘00’.
FIGURE 15-4:
4.
5.
6.
7.
8.
Copy the Initialization Value (IV) to TEXTA at
7C20h.
Set AESST to initiate the encryption.
Copy the ciphertext message to TEXTB at
7C30h.
Wait for the hardware to clear AESST.
Read the plaintext message from XOROUT at
7C40h.
To decipher additional blocks, copy the previous
block’s ciphertext to TEXTA, then repeat steps 4
through 7.
The context for CFB mode consists of both the AES
encryption key and the ciphertext from the most recent
block. Save the ciphertext from the previous block to be
used as the IV when resuming the operation for
additional blocks.
15.3.3.4
Output Feedback Mode (OFB)
Output Feedback mode is nearly identical to CFB
mode, except that in OFB mode, the Initialization Value
(IV) for subsequent blocks is the output of the AES
operation, not the ciphertext. The IV is encrypted using
the AES engine, then XORed with the plaintext to form
the ciphertext. Like CBC and CFB modes, identical
subsequent plaintext blocks will use a different IV, and
therefore, yield different ciphertext blocks. However,
unlike CBC and CFB modes, this IV does not depend
on the plaintext. Figure 15-4 depicts the use of OFB
mode for encryption and decryption.
OFB ENCRYPTION AND DECRYPTION
DECRYPTION
ENCRYPTION
IV
Key
DATA
KEY
DATA
Key
IV
Key
KEY
DATA
KEY
ENCRYPTER
ENCRYPTER
Plaintext0
Plaintext1
Ciphertext0
 2010 Microchip Technology Inc.
Ciphertext1
ENCRYPTER
Ciphertext0
Plaintext0
Key
DATA
KEY
ENCRYPTER
Ciphertext1
Plaintext1
DS39935C-page 133
ENC424J600/624J600
To encrypt a block using OFB mode:
1.
2.
3.
4.
5.
6.
7.
8.
Load the encryption key as described in
Section 15.3.1 “Key Support”.
Set AESOP<1:0> (ECON1<10:9>) to ‘00’.
Copy the Initialization Value (IV) to TEXTA at
7C20h.
Set AESST (ECON1<11>) to initiate the
encryption.
Copy the plaintext message to TEXTB at
7C30h.
Wait for the hardware to clear AESST.
Read the ciphertext message from XOROUT at
7C40h.
Repeat steps 4 through 7 for subsequent blocks.
The encryption output from the previous block
automatically becomes the IV for the following
block.
To decrypt a block using OFB mode:
1.
2.
3.
4.
5.
Load the encryption key as described in
Section 15.3.1 “Key Support”. Note that this
mode does not make use of a decryption key.
Set AESOP<1:0> to ‘00’.
Copy the Initialization Value (IV) to TEXTA at
7C20h.
Set AESST to initiate the encryption.
Copy the ciphertext message to TEXTB at
7C30h.
FIGURE 15-5:
6.
7.
8.
Wait for the hardware to clear AESST.
Read the plaintext message from XOROUT at
7C40h.
Repeat steps 4 through 7 for subsequent blocks.
The context for OFB mode consists of both the AES
encryption key and the encryption output from the most
recent block. Save the encryption block output from
TEXTA at 7C20h to be used as the IV when resuming
the operation for additional blocks.
15.3.3.5
Counter Mode (CTR)
Counter mode is not directly supported by hardware,
but can be implemented with software assistance. In
CTR mode, a counter is used as the input to the
encryption block. The encrypted output is then XORed
with the plaintext to yield the ciphertext, or vice versa.
The counter does not necessarily need to be a true
counter; any practically non-repeating function will
suffice. When using CTR mode, the application must
load the counter value before each block.
Since each block depends on the counter value, identical subsequent plaintext blocks will yield different
ciphertext blocks. Whether or not these blocks are
independent will depend on the selected counter
function. Figure 15-5 shows the use of CTR mode for
encryption and decryption.
CTR ENCRYPTION AND DECRYPTION
DECRYPTION
ENCRYPTION
CTR0
Key
CTR1
Key
CTR0
Key
CTR1
Key
DATA
KEY
DATA
KEY
DATA
KEY
DATA
KEY
ENCRYPTER
ENCRYPTER
Plaintext0
Plaintext1
Ciphertext0
DS39935C-page 134
Ciphertext1
ENCRYPTER
Ciphertext0
Plaintext0
ENCRYPTER
Ciphertext1
Plaintext1
 2010 Microchip Technology Inc.
ENC424J600/624J600
To encrypt a block using CTR mode:
To decrypt a block using CTR mode:
1.
1.
2.
3.
4.
5.
6.
7.
8.
Load the encryption key as described in
Section 15.3.1 “Key Support”.
Set AESOP<1:0> (ECON1<10:9>) to ‘00’.
Copy the counter value to TEXTA at 7C20h.
Set AESST (ECON1<11>) to initiate the
encryption.
Copy the plaintext message to TEXTB at
7C30h.
Wait for the hardware to clear AESST.
Read the ciphertext message from XOROUT at
7C40h.
Repeat steps 3 through 7 for subsequent blocks.
2.
3.
4.
5.
6.
7.
8.
Load the encryption key as described in
Section 15.3.1 “Key Support”. Note that this
mode does not make use of a decryption key.
Set AESOP<1:0> to ‘00’.
Copy the counter value to TEXTA at 7C20h.
Set AESST to initiate the encryption.
Copy the ciphertext message to TEXTB at
7C30h.
Wait for the hardware to clear AESST.
Read the plaintext message from XOROUT at
7C40h.
Repeat steps 3 through 7 for subsequent blocks.
The context for CTR mode consists of the AES encryption key and the counter value. It is up to the application
to determine what needs to be saved for the counter
value context.
 2010 Microchip Technology Inc.
DS39935C-page 135
ENC424J600/624J600
NOTES:
DS39935C-page 136
 2010 Microchip Technology Inc.
ENC424J600/624J600
16.0
POWER-SAVING FEATURES
Due to the high bandwidth and long cable length requirements, Ethernet applications can utilize a significant
amount of power. ENC424J600/624J600 devices
include power-down and PHY power management
features to assist low-power applications. While features
cannot completely mitigate power requirements, they
can help reduce power consumption when the Ethernet
interface is not needed.
16.1
General Power-Down
The ENCX24J600 may be placed in Power-Down
mode through the command interface. In this mode, the
device will no longer be able to transmit or receive any
packets or perform DMA operations. However, most
registers, and all buffer memories, retain their states
and remain accessible by the host controller. The clock
driver also remains operational, leaving the CLKOUT
function unaffected. However, the MAC/MII and PHY
registers all become inaccessible, and the PHY
registers lose their current states.
To power-down the Ethernet interface:
1.
2.
3.
4.
5.
6.
Turn off the Modular Exponentiation and AES
engines by clearing CRYPTEN (EIR<15>).
Turn off packet reception by clearing RXEN
(ECON1<0>).
Wait for any in-progress receptions to complete
by polling RXBUSY (ESTAT<13>) until it is clear.
Wait for any current transmission operation to
complete by verifying that TXRTS (ECON1<1>)
is clear.
Power-down the PHY by setting the PSLEEP bit
(PHCON1<11>).
Power-down the Ethernet interface by clearing
ETHEN and STRCH (ECON2<15,14>). Disabling the LED stretching behavior is necessary
to ensure no LEDs get trapped in a perpetually
illuminated state in the event they are being
stretched on when ETHEN is cleared.
After leaving Sleep mode, there will be a delay of
several hundred milliseconds before a new link is
established. If the host controller attempts to transmit
any Ethernet packets before the link is established, the
PHY will suppress the transmission onto the wire to
avoid interfering with auto-negotiation or violating
IEEE 802.3 standards. The link status can be monitored through the Link Change Interrupt Flag, LINKIF
(EIR<11>), and PHYLNK status bit (ESTAT<8>).
16.2
Energy Detect Power-Down
ENC424J600/624J600 devices also support an Energy
Detect Power-Down mode. In this mode, the PHY
remains powered down until a signal is detected on the
Ethernet interface. While no packets can be sent or
received, the internal PHY configuration is maintained.
This is useful for applications in which the Ethernet
cable may not always be connected, but need to
automatically activate when a network cable is
attached by the user and a link partner is detected.
When a signal is detected on the Ethernet medium, the
EDSTAT flag (PHCON2<1>) is set.
To enable Energy Detect Power-Down mode, set the
EDPWRDN bit (PHCON2<13>). The PHY automatically powers up and down based on the value of
EDSTAT. When in Energy Detect Power-Down, the
host microcontroller should monitor the Ethernet link
status via the LINKIF interrupt flag and PHYLNK status
bit. When linked, it should set ETHEN and STRCH
(ECON2<15,14>) and begin using the network interface as normal. When unlinked, it should clear ETHEN
and STRCH to save power. To resume normal operation, clear EDPWRDN. While the PHY is in Energy
Detect Power-Down mode, the transmit logic will
indefinitely hold off transmissions when unlinked.
Therefore, if the application attempts to transmit a
packet by setting TXRTS (ECON1<1>), this bit may not
clear itself or cause a transmit interrupt to occur until
the user plugs the device into another link partner.
To resume normal operation, the PHY registers need to
be reconfigured after wake-up. The typical restart
sequence is:
1.
2.
3.
Wake-up the Ethernet interface by setting
ETHEN and STRCH (ECON2<15,14>).
Wake-up the PHY by clearing PSLEEP
(PHCON1<11>). Care should be taken to modify
only the PSLEEP bit.
Restore receive capabilities by setting RXEN
(ECON1<0>).
 2010 Microchip Technology Inc.
DS39935C-page 137
ENC424J600/624J600
A device in Energy Detect Power-Down mode does not
transmit link pulses, but passively listens for the remote
link partner to transmit a signal in order to wake the
device. If the remote device is also in a similar Passive
Listening mode, neither device will wake-up. This
should not cause problems for normal Ethernet
equipment, such as switches and routers, but may
raise concerns if two embedded devices using this
feature will be connected directly.
Note:
Through compatibility testing, it has been
observed that some 3rd party Ethernet
products do not transmit link pulses that
are compliant with the IEEE 802.3 standard timing requirements. For such
devices, the ENCX24J600 PHY energy
detect feature may be unable to wake-up.
Before enabling Energy Detect PowerDown, application designers should weigh
the compatibility risks of using this feature,
and where possible, implement a means
of disabling it by the end product user.
DS39935C-page 138
16.3
External Power-Down
For applications that are extremely power-sensitive
and have no need for memory or register retention, it
may be useful to control the device using an external
power-down circuit. This allows the host controller to
completely remove power from the device. External
power-down circuitry can be designed with either a
MOSFET on the power supply pins, or by using a
regulator with output enable capabilities.
Keep in mind that an externally controlled powerdown will require the ENCX24J600 to be completely
re-initialized, as described in Section 8.0 “Initialization”.
 2010 Microchip Technology Inc.
ENC424J600/624J600
REGISTER 16-1:
PHCON2: PHY CONTROL REGISTER 2
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
r
r
EDPWRDN
r
EDTHRES
r
r
r
bit 15
bit 8
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R-1
R/W-0
r
r
r
r
r
FRCLNK
EDSTAT
r
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 15-14
Reserved: Write as ‘0’, ignore on read
bit 13
EDPWRDN: Energy Detect Power-Down Enable bit
1 = Energy detect power-down enabled. PHY automatically powers up and down based on the state
of EDSTAT.
0 = Energy detect power-down disabled. Use this setting for maximal compatibility.
bit 12
Reserved: Write as ‘0’, ignore on read
bit 11
EDTHRES: Energy Detect Threshold Control bit
1 = Less energy is required to wake the PHY from energy detect power-down
0 = Normal energy detect threshold
bit 10-3
Reserved: Write as ‘0’, ignore on read
bit 2
FRCLNK: Force Link Control bit
1 = Force immediate link up, even when no link partner is present (100 Mbps operation only)(1)
0 = Normal operation
bit 1
EDSTAT: Energy Detect Status bit
1 = Energy detect circuit has detected energy on the TPIN+/- pins within the last 256 ms
0 = No energy has been detected on the TPIN+/- pins within the last 256 ms
bit 0
Reserved: Write as ‘0’, ignore on read
Note 1:
Intended for testing purposes only. Do not use in 10 Mbps operation.
 2010 Microchip Technology Inc.
DS39935C-page 139
ENC424J600/624J600
NOTES:
DS39935C-page 140
 2010 Microchip Technology Inc.
ENC424J600/624J600
17.0
ELECTRICAL CHARACTERISTICS
Absolute Maximum Ratings
Storage temperature ...............................................................................................................................-65°C to +150°C
Ambient temperature under bias............................................................................................. -40°C to +85°C (Industrial)
Voltage on VDD, VDDOSC, VDDPLL, VDDRX and VDDTX, with respect to VSS ................................................. -0.3V to 4.0V
Voltage on any digital pin, with respect to VSS ............................................................................................. -0.3V to 6.0V
Voltage on OSC1 and RBIAS analog pins, with respect to VSS .........................................................-0.3V to VDD + 0.3V
Voltage on TPIN+/- and TPOUT+/-, with respect to VSS .............................................................................. -0.3V to 5.0V
Voltage on VCAP, with respect to all VSS pins (Note 1) ................................................................................ -0.3V to 2.0V
ESD protection on all pins.......................................................................................................................................... 2 kV
Current sourced or sunk by any digital output pin...................................................................................................25 mA
Current out of all VSS pins.....................................................................................................................................420 mA
Current into all VDD pins........................................................................................................................................300 mA
Note 1: VCAP is not designed to supply an external load. No external voltage should be applied to this pin.
† Notice: Stresses above those listed under “Maximum Ratings” may cause permanent damage to the device. This
is a stress rating only and functional operation of the device at those or any other conditions above those indicated in
the operational listings of this specification is not implied. Exposure to maximum rating conditions for extended periods
may affect device reliability.
 2010 Microchip Technology Inc.
DS39935C-page 141
ENC424J600/624J600
17.1
DC Characteristics: ENC424J600/624J600
TABLE 17-1:
THERMAL OPERATING CONDITIONS
Rating
Symbol
Min
Typ
Max
Unit
Operating Junction Temperature Range
TJ
-40
—
+125
°C
Operating Ambient Temperature Range
TA
-40
—
+85
°C
ENC424J600/624J600:
Power Dissipation:
Internal Chip Power Dissipation:
PINT = VDD x (IDD –  IOH)
PD
PINT + PI/O
W
PDMAX
(TJ – TA)/JA
W
I/O Pin Power Dissipation:
PI/O =  ({VDD – VOH} x IOH) +  (VOL x IOL) + ((VTPOUT+ +
VTPOUT-)/2 x ITXCT)
Maximum Allowed Power Dissipation
TABLE 17-2:
THERMAL PACKAGING CHARACTERISTICS
Characteristic
Symbol
Typ
Max
Unit
Notes
Package Thermal Resistance, 44-Pin QFN (8x8x1 mm)
JA
28
—
°C/W
(Note 1)
Package Thermal Resistance, 44-Pin TQFP (10x10x1 mm)
JA
49.8
—
°C/W
(Note 1)
Package Thermal Resistance, 64-Pin TQFP (10x10x1 mm)
JA
47
—
°C/W
(Note 1)
Note 1:
Junction to ambient thermal resistance, Theta-JA (JA) numbers are achieved by package simulations.
DS39935C-page 142
 2010 Microchip Technology Inc.
ENC424J600/624J600
TABLE 17-3:
DC CHARACTERISTICS: ENC424J600/624J600 (INDUSTRIAL)
Standard Operating Conditions:
-40°C  TA  85°C, 3.0V  VDD  3.6V (Industrial)
DC CHARACTERISTICS
Param.
No.
Sym
Characteristic
Min
Typ
Max
Units Conditions
D001
VDD
Supply Voltage
3.0
3.3
3.6
V
D002
VPOR
VDD Start Voltage to Ensure Internal
Power-on Reset Signal
1.75
—
1.95
V
D003
SVDD
VDD Rise Rate to Ensure Internal
Power-on Reset Signal
0.05
—
—
V/ms
Digital Input Pins
0.6 VDD
—
5.5
V
OSC1 Pin
0.7 VDD
—
VDD
V
VIH
D004
D005
VIL
V
Input High Voltage
Input Low Voltage
D006
Digital Input Pins
VSS
—
0.2 VDD
V
D007
OSC1 Pin
VSS
—
0.2 VDD
V
2.4
—
VDD
V
IOH = -8mA
All Digital Output Pins
VSS
—
0.4
V
IOL = 8mA
IWPU
Weak Pull-up Current
-150
-260
-400
A
VDD = 3.3V,
VPIN = VSS
IWPD
Weak Pull-Down Current
28
56
112
A
VDD = 3.3V,
VPIN = VDD
IIL
Input Leakage Current
VOH
Output High Voltage
All Digital Output Pins
VOL
IDD
Output Low Voltage
Digital Input Pins
—
—
±1
A
VSS  VPIN  VDD
OSC1 Pin
—
—
±150
A
VSS  VPIN  VDD
—
74
—
mA
(Note 1)
Supply Current
Not Linked
100Base-TX Linked, Idle
—
96
—
mA
(Note 1)
100Base-TX Linked, Maximum TX
Utilization
—
96
117
mA
(Note 1)
10Base-T Linked, Idle
—
82
—
mA
(Note 1)
10Base-T Linked, Maximum TX
Utilization
—
82
103
mA
(Note 1)
ICT
Cryptographic Module Current
—
40
—
mA
EIR<15> = 1
ITXCT
TX Transformer Center Tap Current
—
1
—
mA
Not Linked
Note 1:
2:
3:
100Base-TX Linked
—
30
—
mA
10Base-T Linked
—
80
—
mA
Excludes TX transformer center tap and LEDA/LEDB currents; cryptographic engine module disabled
(EIR<15> = 0).
Cryptographic engine module disabled (EIR<15> = 0), auto-negotiation disabled (PHCON1<12> = 0) and
Ethernet disabled (ECON2<15> = 0).
Measured across 100Ω termination on cable side of transformer.
 2010 Microchip Technology Inc.
DS39935C-page 143
ENC424J600/624J600
TABLE 17-3:
DC CHARACTERISTICS: ENC424J600/624J600 (INDUSTRIAL) (CONTINUED)
Standard Operating Conditions:
-40°C  TA  85°C, 3.0V  VDD  3.6V (Industrial)
DC CHARACTERISTICS
Param.
No.
Sym
Characteristic
Min
Typ
Max
Energy Detect Power-Down
—
29.2
34
mA
PHCON2<13> = 1
Sleep
—
23.8
28
mA
PHCON1<11> = 1
Power-Down Current(2)
IPD
VTPOUT Peak Differential Output Voltage
VSQ
Note 1:
2:
3:
Units Conditions
V
100Base-TX
0.95
1.00
1.05
V
(Note 3)
10Base-T
2.2
2.5
2.8
V
(Note 3)
10Base-T RX Differential Squelch
Threshold
160
300
585
mV
Excludes TX transformer center tap and LEDA/LEDB currents; cryptographic engine module disabled
(EIR<15> = 0).
Cryptographic engine module disabled (EIR<15> = 0), auto-negotiation disabled (PHCON1<12> = 0) and
Ethernet disabled (ECON2<15> = 0).
Measured across 100Ω termination on cable side of transformer.
TABLE 17-4:
INTERNAL VOLTAGE REGULATOR SPECIFICATIONS
Operating Conditions: -40°C < TA < +85°C (unless otherwise stated)
Param
No.
Symbol
Characteristics
Min
Typ
Max
Units
VRGOUT
Regulator Output Voltage
1.62
1.80
1.98
V
CEFC
External Filter Capacitor
Value
4.7
10
—
F
TABLE 17-5:
Comments
Capacitor must have low
series resistance (< 3
REQUIREMENTS FOR EXTERNAL MAGNETICS
Parameter
Min
Norm
Max
Units
RX Transformer Turns Ratio
—
1:1
—
—
TX Transformer Turns Ratio
—
1:1
—
—
Insertion Loss
—
—
1.1
dB
350
—
—
H
—
1.5
—
kV
Differential to Common-Mode Rejection
40
—
—
dB
Return Loss
-16
—
—
dB
Primary Inductance
Transformer Isolation
DS39935C-page 144
Conditions
Transformer Center Tap = 3.3V
8 mA bias
0.1 to 10 MHz
 2010 Microchip Technology Inc.
ENC424J600/624J600
17.2
AC Characteristics: ENC424J600/624J600 (Industrial)
Standard Operating Conditions
-40°C TA +85°C, 3.00V VDD 3.60V (Industrial)
AC CHARACTERISTICS
TABLE 17-6:
Param.
No.
Sym
Note 1:
Min
Max
Units
Clock In Frequency
25
25
MHz
TOSC
Clock In Period
40
40
ns
TDUTY
Duty Cycle
(external clock input)
40
60
%
f
Clock Frequency Error
—
50
ppm
Conditions
CLKOUT PIN TIMING SPECIFICATIONS
Sym
Characteristic
Min
Typ
Max
Units
Conditions
FCLKOUT
CLKOUT Frequency
DC
—
33.3
MHz
TDUTY
CLKOUT Duty Cycle
40
50
60
%
All prescaler settings except
divide by 12.5
37.5
47.5
57.5
%
Divide by 12.5 prescaler
TABLE 17-8:
Param.
No.
Characteristic
FOSC
TABLE 17-7:
Param.
No.
OSCILLATOR TIMING CHARACTERISTICS
CLKOUT PIN AC CHARACTERISTICS
Sym
Characteristic
Min
Max
Units
—
3
ns
(Note 1)
(Note 1)
trCLKOUT
CLKOUT Pin Rise Time
tfCLKOUT
CLKOUT Pin Fall Time
—
4
ns
CLKOUT
CLKOUT Stability (jitter)
—
±0.25
%
Conditions
Measured from 0.1 VDD to 0.9 VDD with a load of 10 pF.
 2010 Microchip Technology Inc.
DS39935C-page 145
ENC424J600/624J600
FIGURE 17-1:
SPI INPUT TIMING
TCSD
1/FSCK
CS
TCSH
TCSS
SCK
TSU
SI
THD
MSb In
LSb In
High-Impedance
SO
FIGURE 17-2:
SPI OUTPUT TIMING
CS
1/FSCK
SCK
TV
SO
TV
TDIS
MSb Out
LSb Out
Don’t Care
SI
LSb In
TABLE 17-9:
SPI INTERFACE AC CHARACTERISTICS
Sym
Characteristic
Min
Typ
Max
Units
FSCK
SPI Clock Frequency
DC
—
14
MHz
TDUTY
SCK Duty Cycle
45
—
55
%
Conditions
TCSS
CS Setup Time
50
—
—
ns
TCSH
CS Hold Time
50
—
—
ns
TCSD
CS Disable Time
20
—
—
ns
TSU
Data Setup Time
10
—
—
ns
THD
Data Hold Time
10
—
—
ns
TV
Output Valid from Clock Low
—
—
10
ns
Load on SO pin = 30 pF
TDIS
Output Disable Time
—
—
10
ns
Load on SO pin = 30 pF
DS39935C-page 146
 2010 Microchip Technology Inc.
ENC424J600/624J600
TABLE 17-10: PSP INTERFACE TIMING SPECIFICATIONS
Sym
Characteristic
Min
Typ
Max
Units
TPSP1
CS, Address, R/W Setup Time
1
—
—
ns
TPSP2
RD, EN, BxSEL to Data Valid
—
—
75
ns
TPSP3
Data Output Hold Time
0
—
3
ns
TPSP4
RD, EN, BxSEL Deassertion
Time
4.5
—
—
ns
TPSP5
CS, R/W Setup Time
3.5
—
—
ns
TPSP6
Address Setup Time
3.5
—
—
ns
TPSP7
Data Setup Time
3.5
—
—
ns
TPSP8
WR, WRL, WRH, EN, BxSEL
Assertion Time
6.5
—
—
ns
Comments
TPSP9
Address Hold Time
1
—
—
ns
TPSP10
Data Input Hold Time
1
—
—
ns
TPSP11
WR, WRL, WRH, EN, BxSEL
Deassertion Time
4.5
—
—
ns
SFR access
40
—
—
ns
SRAM access
TPSP12
CS, Address Setup Time
6.5
—
—
ns
TPSP13
AL Assertion Time
6.5
—
—
ns
TPSP14
Address Hold Time
1
—
—
ns
TPSP15
AL Deassertion Time
4
—
—
ns
 2010 Microchip Technology Inc.
DS39935C-page 147
ENC424J600/624J600
NOTES:
DS39935C-page 148
 2010 Microchip Technology Inc.
ENC424J600/624J600
18.0
PACKAGING INFORMATION
18.1
Package Marking Information
44-Lead QFN
Example
XXXXXXXXXX
XXXXXXXXXX
XXXXXXXXXX
YYWWNNN
44-Lead TQFP
Example
XXXXXXXXXX
XXXXXXXXXX
XXXXXXXXXX
YYWWNNN
64-Lead TQFP (10x10x1mm)
XXXXXXXXXX
XXXXXXXXXX
XXXXXXXXXX
YYWWNNN
Legend: XX...X
Y
YY
WW
NNN
*
Note:
ENC424J600
-I/ML e3
1010017
ENC424J600
-I/PT e3
1010017
Example
ENC624J600
-I/PT e3
1010017
Customer-specific information
Year code (last digit of calendar year)
Year code (last 2 digits of calendar year)
Week code (week of January 1 is week ‘01’)
Alphanumeric traceability code
Pb-free JEDEC designator for Matte Tin (Sn)
This package is Pb-free. The Pb-free JEDEC designator ( e3 )
can be found on the outer packaging for this package.
In the event the full Microchip part number cannot be marked on one line, it will
be carried over to the next line, thus limiting the number of available
characters for customer-specific information.
 2010 Microchip Technology Inc.
DS39935C-page 149
ENC424J600/624J600
18.2
Package Details
The following sections give the technical details of the
packages.
!
"
3&'!&"&
+#*!(
!!&
+
%&&#&
&&
244***'
'4
+
D
D2
EXPOSED
PAD
e
E
E2
b
2
2
1
N
1
N
NOTE 1
TOP VIEW
K
L
BOTTOM VIEW
A
A3
A1
5&!
'!6'&!
7"')%!
66--
7
7
78
9
&
8 :&
;
&#%%
/
1&&+!!
,
8 <#&
-
-$
!##<#&
-
8 6&
-$
!##6&
/01
-3
;01
,
/
;
;01
,
/
1&&<#&
)
/
,
,;
1&&6&
6
,
/
1&&&-$
!##
=
>
"
!"#$%&"' ()"&'"!&)&#*&&&#
+!!*!"&#
, '!#&
-./
012 0!'!&$& "!**&"&&!
-32 %'!("!"*&"&&(%%'&
"
!!
;
>
* 1,0
DS39935C-page 150
 2010 Microchip Technology Inc.
ENC424J600/624J600
!
"
3&'!&"&
+#*!(
!!&
+
%&&#&
&&
244***'
'4
+
 2010 Microchip Technology Inc.
DS39935C-page 151
ENC424J600/624J600
#$%
&#'('(')*(( #!
"
3&'!&"&
+#*!(
!!&
+
%&&#&
&&
244***'
'4
+
D
D1
E
e
E1
N
b
NOTE 1
1 2 3
NOTE 2
α
A
c
φ
β
L
A1
5&!
'!6'&!
7"')%6#!
A2
L1
66--
7
7
78
9
6#&
8 :&
>
;01
>
##++!!
/
/
&#%%
/
>
/
3&6&
6
/
/
3&
&
6
-3
3&
I
8 <#&
-
A
01
,/A
8 6&
01
##+<#&
-
01
##+6&
01
A
6#+!!
>
6#<#&
)
,
,
/
#%&
D
A
A
,A
#%&0&&'
E
A
A
,A
"
!"#$%&"' ()"&'"!&)&#*&&&#
1'%!&!
&[email protected]' , '!!#-#&"#'#%!
&"!!#%!
&"!!!&$#/''
!#
'!#&
-./
012 0!'!&$& "!**&"&&!
-32 %'!("!"*&"&&(%%'&
"
!!
* 10
DS39935C-page 152
 2010 Microchip Technology Inc.
ENC424J600/624J600
#$%
&#'('(')*(( #!
"
3&'!&"&
+#*!(
!!&
+
%&&#&
&&
244***'
'4
+
 2010 Microchip Technology Inc.
DS39935C-page 153
ENC424J600/624J600
+
#$%
&#'('(')*(( #!
"
3&'!&"&
+#*!(
!!&
+
%&&#&
&&
244***'
'4
+
D
D1
E
e
E1
N
b
NOTE 1
123
NOTE 2
α
A
c
φ
A2
β
A1
L
L1
5&!
'!6'&!
7"')%6#!
66--
7
7
78
9
6#&
8 :&
>
/01
>
##++!!
/
/
&#%%
/
>
/
3&6&
6
/
/
3&
&
6
-3
3&
I
8 <#&
-
A
01
,/A
8 6&
01
##+<#&
-
01
##+6&
01
A
6#+!!
>
6#<#&
)
#%&
D
A
A
,A
#%&0&&'
E
A
A
,A
"
!"#$%&"' ()"&'"!&)&#*&&&#
1'%!&!
&[email protected]' , '!!#-#&"#'#%!
&"!!#%!
&"!!!&$#/''
!#
'!#&
-./
012 0!'!&$& "!**&"&&!
-32 %'!("!"*&"&&(%%'&
"
!!
* 1;/0
DS39935C-page 154
 2010 Microchip Technology Inc.
ENC424J600/624J600
+
#$%
&#'('(')*(( #!
"
3&'!&"&
+#*!(
!!&
+
%&&#&
&&
244***'
'4
+
 2010 Microchip Technology Inc.
DS39935C-page 155
ENC424J600/624J600
NOTES:
DS39935C-page 156
 2010 Microchip Technology Inc.
ENC424J600/624J600
APPENDIX A:
REVISION HISTORY
Revision A (March 2009)
Original data sheet for ENC424J600/624J600 devices.
Revision B (July 2009)
Removed preliminary from the data sheet. Section 1.0
“Device Overview” and Section 7.0 “Reset” had
minor edits.
Revision C (January 2010)
Section 5.3.3 “MODE 3” and Section 5.3.4 “MODE
4” had minor edits.
 2010 Microchip Technology Inc.
DS39935C-page 157
ENC424J600/624J600
NOTES:
DS39935C-page 158
 2010 Microchip Technology Inc.
ENC424J600/624J600
INDEX
A
AC Characteristics
CLKOUT Pin ............................................................. 145
CLKOUT Pin Timing Specifications .......................... 145
ENC424J600/624J600 (Industrial)............................ 145
Oscillator Timing ....................................................... 145
PSP Interface Timing Specifications......................... 147
SPI Interface ............................................................. 146
Advanced Encryption Standard (AES)
Context Switching ..................................................... 130
Key Support .............................................................. 129
B
Block Diagrams
Alternate TX Choke Topology..................................... 12
Bi-Color LED Connection............................................ 12
CBC Encryption/Decryption ...................................... 131
CFB Encryption/Decryption....................................... 132
Crystal Oscillator Operation .......................................... 9
CTR Encryption/Decryption ...................................... 134
ECB Encryption/Decryption ...................................... 130
ENC424J600/624J600.................................................. 6
Ethernet Packet Format .............................................. 71
Example TX Buffer Wrapping ..................................... 83
External Clock Source .................................................. 9
I/O Level Shifting on SPI Interface
Using 3-State Buffers.......................................... 15
I/O Level Shifting on SPI Interface
Using AND Gates ............................................... 15
Interrupt Logic ........................................................... 117
OFB Encryption/Decryption ...................................... 133
On-Chip Reset Circuit ................................................. 73
PSP External Connections Mode 1............................. 54
PSP External Connections Mode 10........................... 69
PSP External Connections Mode 2............................. 55
PSP External Connections Mode 3............................. 57
PSP External Connections Mode 4............................. 59
PSP External Connections Mode 5............................. 62
PSP External Connections Mode 6............................. 65
PSP External Connections Mode 9............................. 67
RBIAS Resistor ........................................................... 10
Receive Filter Decision Tree....................................... 98
Single Color LED Connection ..................................... 12
Typical Ethernet Magnetics Connections.................... 11
Using INT/SPISEL Pin to Select I/O Interface ............ 13
VCAP Connections....................................................... 10
Buffer Pointers (SRAM Access) .......................................... 34
C
CLKOUT Pin ......................................................................... 9
CRC
Frame Field................................................................. 72
Cryptographic Security Engines
Advanced Encryption Standard (AES)...................... 129
Cipher Block Chaining Mode (CBC) ................. 131
Cipher Feedback Mode (CFB) .......................... 132
Counter Mode (CTR) ........................................ 134
Electronic Code Book Mode (ECB) .................. 130
Output Feedback Mode (OFB) ......................... 133
MD5/SHA-1 Hashing................................................. 126
Context Switching ............................................. 128
Modular Exponentiation ............................................ 125
 2010 Microchip Technology Inc.
Customer Change Notification Service............................. 162
Customer Notification Service .......................................... 162
Customer Support............................................................. 162
D
DC Characteristics
ENC424J600/624J600 (Industrial) ........................... 143
Internal Voltage Regulator........................................ 144
Requirements for External Magnets ......................... 144
Thermal Operating Conditions.................................. 142
Thermal Packaging................................................... 142
Destination Address............................................................ 71
Device Features (table) ........................................................ 5
Device Initialization ....................................................... 75–76
Digital I/O Levels................................................................. 15
Direct Memory Access (DMA) Controller.......................... 123
DMA Controller
Checksum Calculations ............................................ 124
Copying Memory ...................................................... 123
Performance ............................................................. 124
E
E Registers ......................................................................... 19
Electrical Characteristics .................................................. 141
Absolute Maximum Ratings ...................................... 141
ENC424J600/624J600 Register File Summary ............ 26–27
Energy Detect Power-Down ............................................. 137
Equations
Increment Logic for EGPRDPT and EGPWRPT ........ 35
Increment Logic for ERXRDPT and ERXWRPT......... 36
Increment Logic for EUDARDPT
and EUDAWRPT ................................................ 36
Errata .................................................................................... 4
Ethernet
Frame Format............................................................. 71
Ethernet Frame Format ...................................................... 71
Ethernet Overview .............................................................. 71
Examples
Deriving a Hash Table Location ............................... 100
External Connections
CS/CS Pin .................................................................. 15
Digital I/O Levels ........................................................ 15
EMI and Layout Considerations ................................. 12
LEDA and LEDB......................................................... 12
Oscillator....................................................................... 9
PSP Host Interface ..................................................... 14
RBIAS Pin................................................................... 10
SPI Host Interface ...................................................... 14
VCAP Pin ..................................................................... 10
VDD/VSS Pins.............................................................. 10
External Power-Down ....................................................... 138
F
Fast Link Pulses (FLPs).................................................... 109
Flow Control
Automatic Control ..................................................... 106
Full-Duplex Operation............................................... 105
Half-Duplex Operation .............................................. 105
Manual Control ......................................................... 106
Pause Control Frames.............................................. 105
Receive Watermark Register.................................... 106
Frame Padding (Field) ........................................................ 72
DS39935C-page 159
ENC424J600/624J600
G
General Power-Down Sequence....................................... 137
H
Host Interface Pins........................................................ 13–15
I
I/O Level Shifting................................................................. 15
Initialization
After Link Establishment ............................................. 76
CLKOUT Frequency ................................................... 75
MAC ............................................................................ 75
PHY............................................................................. 76
Receive Buffer ............................................................ 75
Receive Filters ............................................................ 75
Reset........................................................................... 75
Transmit Buffer ........................................................... 75
INT Pin ................................................................................ 13
Internet Address................................................................ 162
Interrupts
Sources ............................................................. 121–122
Wake-on-LAN/Remote Wake-up .............................. 122
INTIE
Global Interrupt Enable Bit........................................ 117
M
MAC Registers .................................................................... 19
Magnetics and External Components ................................. 11
MD5 Hashing .................................................................... 126
Memory Map
Cryptographic Data Memory ....................................... 32
PSP............................................................................. 18
SPI .............................................................................. 17
SRAM Indirect Access Pointers .................................. 34
Microchip Internet Web Site .............................................. 162
Modular Exponentiation Engine ........................................ 125
N
N-Byte Instructions
Banked SFR................................................................ 45
SRAM Buffer ............................................................... 49
Unbanked SFR ........................................................... 47
O
Oscillator ............................................................................... 9
P
Packaging
Details ....................................................................... 150
Marking ..................................................................... 149
Parallel Slave Port Interface (PSP)
External Connections .................................................. 14
Mode 1 ........................................................................ 53
Mode 10 ...................................................................... 69
Mode 2 ........................................................................ 55
Mode 3 ........................................................................ 57
Mode 4 ........................................................................ 59
Mode 5 ........................................................................ 61
Mode 6 ........................................................................ 64
Mode 9 ........................................................................ 67
Performance Considerations ...................................... 53
Physical Implementation ............................................. 51
Using The Interface..................................................... 52
PHY Register File Summary ............................................... 31
PHY Registers..................................................................... 28
PHY Subystem Reset ......................................................... 74
DS39935C-page 160
Pin Functions
A14:A0 .......................................................................... 7
AD15:AD0..................................................................... 7
AL ................................................................................. 7
B0SEL/B1SEL .............................................................. 7
CLKOUT ....................................................................... 7
CS/CS........................................................................... 7
EN................................................................................. 7
INT ................................................................................ 7
LEDA/LEDB .................................................................. 7
OSC1/OSC2 ................................................................. 8
PSPCFG4:PSPCFG0 ................................................... 8
RBIAS ........................................................................... 8
RD ................................................................................ 8
RW................................................................................ 8
SCK .............................................................................. 8
SI .................................................................................. 8
SO ................................................................................ 8
SPISEL ......................................................................... 8
TPIN+/TPIN- ................................................................. 8
TPOUT+/TPOUT- ......................................................... 8
VCAP ............................................................................. 8
VDD/VSS ........................................................................ 8
VDDOSC/VSSOSC ........................................................... 8
VDDPLL/VSSPLL .............................................................. 8
VDDRX/VSSRX ................................................................ 8
VDDTX/VSSTX................................................................. 8
WR................................................................................ 8
WRH/WRL .................................................................... 8
Pinout Descriptions........................................................... 7–8
Power-on Reset .................................................................. 73
Power-Saving Features .................................................... 137
PSP Mode Selection (table)................................................ 14
R
Reader Response............................................................. 163
Receive Filters .................................................................... 72
Broadcast Collection................................................. 100
CRC Error Collection/Rejection .................................. 99
Hash Table Collection............................................... 100
Magic Packet Collection ........................................... 101
Multicast Collection................................................... 100
Not-Me Unicast Collection .......................................... 99
Pattern Match Collection........................................... 102
Pattern Match Collection (example).......................... 103
Promiscuous Mode ................................................... 102
Runt Error Collection/Rejection .................................. 99
Unicast Collection ....................................................... 99
Receive Only Reset ............................................................ 74
Receiving Packets ........................................................ 86–87
Configuring Reception ................................................ 87
ERXHEAD/ERXTAIL Buffer Wrap (example) ............. 86
Incoming Packet Storage............................................ 87
Receive Status Vector ................................................ 89
Receive Status Vector (RSV) ..................................... 87
Received Packet in Buffer Memory (example) ........... 88
Status Vectors ............................................................ 89
Register Maps
CLR (8-Bit PSP).......................................................... 24
SET (8-Bit PSP).......................................................... 23
SET/CLR (16-Bit PSP)................................................ 25
 2010 Microchip Technology Inc.
ENC424J600/624J600
Registers
ECON1 (Ethernet Control 1) ....................................... 90
ECON2 (Ethernet Control 2) ....................................... 77
EIDLED (Ethernet ID Status/LED Control).................. 79
EIE (Ethernet Interrupt Enable)................................. 120
EIR (Ethernet Interrupt Flag)..................................... 118
ERXFCON (Ethernet RX Filter Control)...................... 96
ERXWM (Receive Watermark) ................................. 106
ESTAT (Ethernet Status) ............................................ 93
ETXSTAT (Ethernet Transmit Status)......................... 92
MABBIPG (MAC Back-to-Back
Inter-Packet Gap) ............................................... 81
MACLCON (MAC Collision Control) ........................... 82
MACON1 (MAC Control 1)........................................ 107
MACON2 (MAC Control 2).......................................... 80
MAIPG (MAC Inter-Packet Gap)................................. 82
MICMD (MII Management Command)........................ 30
MIREGADR (MII Management Address) .................... 29
MISTAT (MII Management Status) ............................. 30
PHANA (PHY Auto-Negotiation
Advertisement).................................................. 113
PHANE (PHY Auto-Negotiation Expansion) ............. 115
PHANLPA (PHY Auto-Negotiation Link
Partner Ability) .................................................. 114
PHCON1 (PHY Control 1)......................................... 110
PHCON2 (PHY Control 2)......................................... 139
PHSTAT1 (PHY Status 1)......................................... 111
PHSTAT2 (PHY Status 2)......................................... 112
PHSTAT3 (PHY Status 3)......................................... 112
Reset
PHY Subsystem.......................................................... 74
Power-on..................................................................... 73
Receive Only............................................................... 74
System ........................................................................ 73
Transmit Only.............................................................. 74
Revision History ................................................................ 157
S
Serial Peripheral Interface (SPI)
External Connections.................................................. 14
Instruction Set ............................................................. 39
Physical Implementation ............................................. 39
SFR. See Special Function Registers................................. 19
SHA-1 Hashing ................................................................. 126
Single Byte Instructions ...................................................... 41
Source Address .................................................................. 72
Special Function Registers ................................................. 19
Address Map
16-Bit PSP .......................................................... 22
8-Bit PSP ............................................................ 21
SPI ...................................................................... 20
PHY Registers ............................................................ 28
Speed/Duplex Auto-Negotiation........................................ 109
Manual Configuration................................................ 109
SPI Instruction Set
N-Byte Instructions
Banked SFR ....................................................... 45
SRAM Buffer ....................................................... 49
Unbanked SFR ................................................... 47
Single Byte Instructions .............................................. 41
Summary Table........................................................... 40
Three-Byte Instructions............................................... 43
Two-Byte Instructions ................................................. 42
 2010 Microchip Technology Inc.
SRAM Buffer....................................................................... 32
Buffer Pointers............................................................ 34
Circular Wrapping
ERXDATA Pointer .............................................. 36
EUDADATA Pointer...................................... 36–37
Circular Wrapping with EGPDATA Pointer ................. 35
Direct Access.............................................................. 33
General Purpose Buffer.............................................. 33
Indirect Access ........................................................... 34
Receive Buffer ............................................................ 33
Transmit Buffer ........................................................... 33
Start-Of-Frame Delimiter .................................................... 71
Start-of-Stream/Preamble Field .......................................... 71
System Reset ..................................................................... 73
T
Three-Byte Instructions....................................................... 43
Timing Diagrams
N-Byte SPI Instruction
(Banked SFR Operations) .................................. 45
N-Byte SPI Opcode
(Unbanked SFR Operations) .............................. 47
N-Byte SPI Opcode Instruction
(SRAM Buffer Operations).................................. 49
PSP Mode 1 Read...................................................... 54
PSP Mode 1 Write ...................................................... 54
PSP Mode 10 Read.................................................... 70
PSP Mode 10 Write .................................................... 70
PSP Mode 2 Read...................................................... 56
PSP Mode 2 Write ...................................................... 56
PSP Mode 3 Read...................................................... 58
PSP Mode 3 Write ...................................................... 58
PSP Mode 4 Read...................................................... 60
PSP Mode 4 Write ...................................................... 60
PSP Mode 5 Read...................................................... 63
PSP Mode 5 Write ...................................................... 63
PSP Mode 6 Read...................................................... 66
PSP Mode 6 Write ...................................................... 66
PSP Mode 9 Read...................................................... 68
PSP Mode 9 Write ...................................................... 68
Single Byte Instruction................................................ 41
SPI Input................................................................... 146
SPI Output ................................................................ 146
Three-Byte Read Instruction....................................... 43
Three-Byte Write Instruction....................................... 43
Two-Byte Instruction (RBSEL Opcode) ...................... 42
Transmit Only Reset ........................................................... 74
Transmitting Packets .................................................... 83–86
Selecting ETXLEN Values (example) ......................... 84
Special Cases............................................................. 85
Transmission Status ................................................... 85
Two-Byte Instructions ......................................................... 42
Type/Length Field ............................................................... 72
W
Wake-on-LAN/Remote Wake-up ...................................... 122
WWW Address ................................................................. 162
WWW, On-Line Support ....................................................... 4
DS39935C-page 161
ENC424J600/624J600
NOTES:
DS39935C-page 162
 2010 Microchip Technology Inc.
ENC424J600/624J600
THE MICROCHIP WEB SITE
CUSTOMER SUPPORT
Microchip provides online support via our WWW site at
www.microchip.com. This web site is used as a means
to make files and information easily available to
customers. Accessible by using your favorite Internet
browser, the web site contains the following
information:
Users of Microchip products can receive assistance
through several channels:
• Product Support – Data sheets and errata,
application notes and sample programs, design
resources, user’s guides and hardware support
documents, latest software releases and archived
software
• General Technical Support – Frequently Asked
Questions (FAQ), technical support requests,
online discussion groups, Microchip consultant
program member listing
• Business of Microchip – Product selector and
ordering guides, latest Microchip press releases,
listing of seminars and events, listings of
Microchip sales offices, distributors and factory
representatives
•
•
•
•
•
Distributor or Representative
Local Sales Office
Field Application Engineer (FAE)
Technical Support
Development Systems Information Line
Customers
should
contact
their
distributor,
representative or field application engineer (FAE) for
support. Local sales offices are also available to help
customers. A listing of sales offices and locations is
included in the back of this document.
Technical support is available through the web site
at: http://support.microchip.com
CUSTOMER CHANGE NOTIFICATION
SERVICE
Microchip’s customer notification service helps keep
customers current on Microchip products. Subscribers
will receive e-mail notification whenever there are
changes, updates, revisions or errata related to a
specified product family or development tool of interest.
To register, access the Microchip web site at
www.microchip.com, click on Customer Change
Notification and follow the registration instructions.
 2010 Microchip Technology Inc.
DS39935C-page 163
ENC424J600/624J600
READER RESPONSE
It is our intention to provide you with the best documentation possible to ensure successful use of your Microchip product. If you wish to provide your comments on organization, clarity, subject matter, and ways in which our documentation
can better serve you, please FAX your comments to the Technical Publications Manager at (480) 792-4150.
Please list the following information, and use this outline to provide us with your comments about this document.
To:
Technical Publications Manager
RE:
Reader Response
Total Pages Sent ________
From: Name
Company
Address
City / State / ZIP / Country
Telephone: (_______) _________ - _________
FAX: (______) _________ - _________
Application (optional):
Would you like a reply?
Y
Device: ENC424J600/624J600
N
Literature Number: DS39935C
Questions:
1. What are the best features of this document?
2. How does this document meet your hardware and software development needs?
3. Do you find the organization of this document easy to follow? If not, why?
4. What additions to the document do you think would enhance the structure and subject?
5. What deletions from the document could be made without affecting the overall usefulness?
6. Is there any incorrect or misleading information (what and where)?
7. How would you improve this document?
DS39935C-page 164
 2010 Microchip Technology Inc.
ENC424J600/624J600
PRODUCT IDENTIFICATION SYSTEM
To order or obtain information, e.g., on pricing or delivery, refer to the factory or the listed sales office.
PART NO.
X
/XX
XXX
Device
Temperature
Range
Package
Pattern
Examples:
a)
b)
Device
ENC424J600, ENC624J600,
ENC424J600T(1), ENC624J600T(1);
VDD range 3.0V to 3.6V
Temperature Range
I
= -40C to
Package
ML
PT
=
=
Pattern
Three-Digit Code or Special Requirements (blank otherwise)
ES = Engineering Sample
+85C
c)
ENC424J600-I/ML = Industrial temp., QFN
package.
ENC424J600-I/PT = Industrial temp., 44 leads
TQFP package.
ENC624J600T-I/PT = Industrial temp.,
64 leads TQFP package, tape and reel.
(Industrial)
QFN (Quad Flat No Lead)
TQFP (Thin Quad Flatpack)
 2010 Microchip Technology Inc.
Note 1:
T
= in tape and reel.
DS39935C-page 165
WORLDWIDE SALES AND SERVICE
AMERICAS
ASIA/PACIFIC
ASIA/PACIFIC
EUROPE
Corporate Office
2355 West Chandler Blvd.
Chandler, AZ 85224-6199
Tel: 480-792-7200
Fax: 480-792-7277
Technical Support:
http://support.microchip.com
Web Address:
www.microchip.com
Asia Pacific Office
Suites 3707-14, 37th Floor
Tower 6, The Gateway
Harbour City, Kowloon
Hong Kong
Tel: 852-2401-1200
Fax: 852-2401-3431
India - Bangalore
Tel: 91-80-3090-4444
Fax: 91-80-3090-4123
India - New Delhi
Tel: 91-11-4160-8631
Fax: 91-11-4160-8632
Austria - Wels
Tel: 43-7242-2244-39
Fax: 43-7242-2244-393
Denmark - Copenhagen
Tel: 45-4450-2828
Fax: 45-4485-2829
India - Pune
Tel: 91-20-2566-1512
Fax: 91-20-2566-1513
France - Paris
Tel: 33-1-69-53-63-20
Fax: 33-1-69-30-90-79
Japan - Yokohama
Tel: 81-45-471- 6166
Fax: 81-45-471-6122
Germany - Munich
Tel: 49-89-627-144-0
Fax: 49-89-627-144-44
Korea - Daegu
Tel: 82-53-744-4301
Fax: 82-53-744-4302
Italy - Milan
Tel: 39-0331-742611
Fax: 39-0331-466781
Atlanta
Duluth, GA
Tel: 678-957-9614
Fax: 678-957-1455
Boston
Westborough, MA
Tel: 774-760-0087
Fax: 774-760-0088
Chicago
Itasca, IL
Tel: 630-285-0071
Fax: 630-285-0075
Cleveland
Independence, OH
Tel: 216-447-0464
Fax: 216-447-0643
Dallas
Addison, TX
Tel: 972-818-7423
Fax: 972-818-2924
Detroit
Farmington Hills, MI
Tel: 248-538-2250
Fax: 248-538-2260
Kokomo
Kokomo, IN
Tel: 765-864-8360
Fax: 765-864-8387
Los Angeles
Mission Viejo, CA
Tel: 949-462-9523
Fax: 949-462-9608
Santa Clara
Santa Clara, CA
Tel: 408-961-6444
Fax: 408-961-6445
Toronto
Mississauga, Ontario,
Canada
Tel: 905-673-0699
Fax: 905-673-6509
Australia - Sydney
Tel: 61-2-9868-6733
Fax: 61-2-9868-6755
China - Beijing
Tel: 86-10-8528-2100
Fax: 86-10-8528-2104
China - Chengdu
Tel: 86-28-8665-5511
Fax: 86-28-8665-7889
China - Chongqing
Tel: 86-23-8980-9588
Fax: 86-23-8980-9500
Korea - Seoul
Tel: 82-2-554-7200
Fax: 82-2-558-5932 or
82-2-558-5934
China - Hong Kong SAR
Tel: 852-2401-1200
Fax: 852-2401-3431
Malaysia - Kuala Lumpur
Tel: 60-3-6201-9857
Fax: 60-3-6201-9859
China - Nanjing
Tel: 86-25-8473-2460
Fax: 86-25-8473-2470
Malaysia - Penang
Tel: 60-4-227-8870
Fax: 60-4-227-4068
China - Qingdao
Tel: 86-532-8502-7355
Fax: 86-532-8502-7205
Philippines - Manila
Tel: 63-2-634-9065
Fax: 63-2-634-9069
China - Shanghai
Tel: 86-21-5407-5533
Fax: 86-21-5407-5066
Singapore
Tel: 65-6334-8870
Fax: 65-6334-8850
China - Shenyang
Tel: 86-24-2334-2829
Fax: 86-24-2334-2393
Taiwan - Hsin Chu
Tel: 886-3-6578-300
Fax: 886-3-6578-370
China - Shenzhen
Tel: 86-755-8203-2660
Fax: 86-755-8203-1760
Taiwan - Kaohsiung
Tel: 886-7-536-4818
Fax: 886-7-536-4803
China - Wuhan
Tel: 86-27-5980-5300
Fax: 86-27-5980-5118
Taiwan - Taipei
Tel: 886-2-2500-6610
Fax: 886-2-2508-0102
China - Xian
Tel: 86-29-8833-7252
Fax: 86-29-8833-7256
Thailand - Bangkok
Tel: 66-2-694-1351
Fax: 66-2-694-1350
Netherlands - Drunen
Tel: 31-416-690399
Fax: 31-416-690340
Spain - Madrid
Tel: 34-91-708-08-90
Fax: 34-91-708-08-91
UK - Wokingham
Tel: 44-118-921-5869
Fax: 44-118-921-5820
China - Xiamen
Tel: 86-592-2388138
Fax: 86-592-2388130
China - Zhuhai
Tel: 86-756-3210040
Fax: 86-756-3210049
01/05/10
DS39935C-page 166
 2010 Microchip Technology Inc.