MICROCHIP PIC16C84

PIC16C84
EEPROM Memory Programming Specification
This document includes the programming
specifications for the following devices:
Pin Diagram
PDIP, SOIC
• PIC16C84
1.0
PROGRAMMING THE PIC16C84
The PIC16C84 is programmed using the serial method.
The serial mode will allow the PIC16C84 to be programmed while in the users system. This allows for
increased design flexibility.
1.1
•1
2
3
4
5
6
7
8
9
PIC16C84
RA2
RA3
RA4/T0CKI
MCLR
VSS
RB0/INT
RB1
RB2
RB3
18
17
16
15
14
13
12
11
10
RA1
RA0
OSC1/CLKIN
OSC2/CLKOUT
VDD
RB7
RB6
RB5
RB4
Hardware Requirements
The PIC16C84 requires one programmable power supply for VDD (4.5V to 5.5V) and a VPP of 12V to 14V. Both
supplies should have a minimum resolution of 0.25V.
1.2
Programming Mode
The programming mode for the PIC16C84 allows programming of user program memory, data memory, special locations used for ID, and the configuration word.
PIN DESCRIPTIONS (DURING PROGRAMMING): PIC16C84
During Programming
Pin Name
Pin Name
Pin Type
Pin Description
RB6
CLOCK
I
RB7
DATA
I/O
Data input/output
MCLR
VTEST MODE
P*
Program Mode Select
VDD
VDD
P
Power Supply
VSS
VSS
P
Ground
Clock input
Legend: I =Input, O = Output, P = Power
*In PIC16C84, programming high voltage is internally generated. To activate the programming mode, high voltage needs to be applied
to MCLR input. This means that MCLR does not draw any significant current.
 1996 Microchip Technology Inc.
DS30189D-page 1
This document was created with FrameMaker 4 0 4
PIC16C84
2.0
PROGRAM MODE ENTRY
2.2
2.1
User Program Memory Map
A user may store identification information (ID) in four ID
locations. The ID locations are mapped in [0x2000 :
0x2003]. It is recommended that the user use only the
four least significant bits of each ID location. In some
devices, the ID locations read-out in a scrambled fashion
after code protection is enabled. For these devices, it is
recommended that ID location is written as “11 1111 1000
bbbb” where 'bbbb' is ID information.
The user memory space extends from 0x0000 to 0x1FFF
(8K), of which 1K (0x0000 - 0x03FF) is physically implemented. In actual implementation the on-chip user program memory is accessed by the lower 10-bits of the PC,
with the upper 3-bits of the PC ignored. Therefore if the
PC is greater than 0x3FF, it will wrap around and address
a location within the physically implemented memory.
(See Figure 2-1).
In programming mode the program memory space
extends from 0x0000 to 0x3FFF, with the first half
(0x0000-0x1FFF) being user program memory and the
second half (0x2000-0x3FFF) being configuration memory. The PC will increment from 0x0000 to 0x1FFF to
0x2000 to 0x3FFF and wrap around to 0x2000 (not to
0x0000). Once in configuration memory, the highest bit of
the PC stays a '1', thus always pointing to the configuration memory. The only way to point to user program memory is to reset the part and reenter program/verify mode
as described in Section 2.3.
ID Locations
In other devices, the ID locations read out normally, even
after code protection. To understand how the devices
behave, refer to Table 4.3.
To understand the scrambling mechanism after code protection, refer to Section 4.0.
In the configuration memory space, 0x2000-0x200F are
physically implemented. Locations beyond 0x200F will
physically access user memory. (See Figure 2-1).
DS30189D-page 2
 1996 Microchip Technology Inc.
EEPROM Memory Programming Specification
FIGURE 2-1:
PROGRAM MEMORY MAPPING
0
3FF
400
Implemented
Non-implemented
1FFF
2000
2000
ID Location
2001
ID Location
2002
ID Location
2003
ID Location
2004
Reserved
2005
Reserved
2006
Reserved
2007
Configuration Word
 1996 Microchip Technology Inc.
Implemented
200F
2010
Non-implemented
3FFF
DS30189D-page 3
PIC16C84
2.3
Program/Verify Mode
Therefore, during a read operation the lsb will be transmitted onto pin RB7 on the rising edge of the second
cycle, and during a load operation the lsb will be
latched on the falling edge of the second cycle. A minimum 1µs delay is also specified between consecutive
commands.
The program/verify mode is entered by holding pins
RB6 and RB7 low while raising MCLR pin from VIL to
VIHH (high voltage). Once in this mode the user program memory and the configuration memory can be
accessed and programmed in serial fashion. The mode
of operation is serial, and the memory that is accessed
is the user program memory. RB6 and RB7 are Schmitt
Trigger Inputs in this mode.
All commands are transmitted lsb first. Data words are
also transmitted lsb first. The data is transmitted on the
rising edge and latched on the falling edge of the clock.
To allow for decoding of commands and reversal of
data pin configuration, a time separation of at least 1 µs
is required between a command and a data word (or
another command).
The sequence that enters the device into the programming/verify mode places all other logic into the reset
state (the MCLR pin was initially at VIL). This means
that all I/O are in the reset state (High impedance
inputs).
2.3.1
The commands that are available are:
2.3.1.1
SERIAL PROGRAM/VERIFY OPERATION
After receiving this command, the program counter
(PC) will be set to 0x2000. By then applying 16 cycles
to the clock pin, the chip will load 14-bits in a “data
word”, as described above, to be programmed into the
configuration memory. A description of the memory
mapping schemes of the program memory for normal
operation and configuration mode operation is shown
in Figure 2-1. After the configuration memory is
entered, the only way to get back to the user program
memory is to exit the program/verify test mode by taking MCLR low (VIL).
The RB6 pin is used as a clock input pin, and the RB7
pin is used for entering command bits and data input/
output during serial operation. To input a command, the
clock pin (RB6) is cycled six times. Each command bit
is latched on the falling edge of the clock with the least
significant bit (lsb) of the command being input first.
The data on pin RB7 is required to have a minimum
setup and hold time (see AC/DC specifications) with
respect to the falling edge of the clock. Commands that
have data associated with them (read and load) are
specified to have a minimum delay of 1 µs between the
command and the data. After this delay, the clock pin is
cycled 16 times with the first cycle being a start bit and
the last cycle being a stop bit. Data is also input and
output lsb first.
TABLE 2-1:
LOAD CONFIGURATION
COMMAND MAPPING (SERIAL OPERATION)
Command
Mapping (MSB ... LSB)
Data
Load Configuration
0
0
0
0
0
0
0, data (14), 0
Load Data for Program Memory
0
0
0
0
1
0
0, data (14), 0
0, data (14), 0
Read Data from Program Memory
0
0
0
1
0
0
Increment Address
0
0
0
1
1
0
Begin Programming
0
0
1
0
0
0
Load Data for Data Memory
0
0
0
0
1
1
0, data (14), 0
0, data (14), 0
Read Data from Data Memory
0
0
0
1
0
1
Bulk Erase Program Memory
0
0
1
0
0
1
Bulk Erase Data Memory
0
0
1
0
1
1
DS30189D-page 4
 1996 Microchip Technology Inc.
EEPROM Memory Programming Specification
FIGURE 2-2:
PROGRAM FLOW CHART - PIC16C84 PROGRAM MEMORY
Start
Set VDD = VDDp
Program Cycle
Read Data
Command
Increment Address
Command
Data Correct?
No
Report Programming
Failure
Yes
No
Program Cycle
Load Data
Command
All Locations Done?
Yes
Verify all Locations
@ VDD min.
Data Correct?
Begin Programming
Command
No
Report Verify Error
@ VDD min.
No
Report Verify Error
@ VDD max.
Wait 10 ms
Yes
Verify all Locations
@ VDD max.
Data Correct?
Yes
Done
 1996 Microchip Technology Inc.
DS30189D-page 5
PIC16C84
FIGURE 2-3:
PROGRAM FLOW CHART - PIC16C84 CONFIGURATION MEMORY
Start
Load Configuration
Command
Program ID
Location?
No
Yes
Increment Address
Command
Read Data
Command
Program Cycle
Report Programming
Failure
No
Data Correct
Yes
No
Address = 0x2004
Yes
Increment Address
Command
Increment Address
Command
Increment Address
Command
Program Cycle
(Config. Word)
Report Program
Config. Word Error
No
Done
DS30189D-page 6
Yes
Data Correct?
No
Data Correct?
Set VDD = VDD max.
Read Data
Command
Yes
Set VDD = VDD min.
Read Data Command
 1996 Microchip Technology Inc.
EEPROM Memory Programming Specification
2.3.1.2
LOAD DATA FOR PROGRAM MEMORY
After receiving this command, the chip will load in a 14bit “data word” when 16 cycles are applied, as
described previously. A timing diagram for the load data
command is shown in Figure 5-1.
2.3.1.3
LOAD DATA FOR DATA MEMORY
After receiving this command, the chip will load in a 14bit “data word” when 16 cycles are applied. However,
the data memory is only 8-bits wide, and thus only the
first 8-bits of data after the start bit will be programmed
into the data memory. It is still necessary to cycle the
clock the full 16 cycles in order to allow the internal circuitry to reset properly. The data memory contains 64
words. Only the lower 8-bits of the PC are decoded by
the data memory, and therefore if the PC is greater
than 0x3F, it will wrap around and address a location
within the physically implemented memory.
2.3.1.4
READ DATA FROM PROGRAM
MEMORY
After receiving this command, the chip will transmit
data bits out of the program memory (user or configuration) currently accessed starting with the second rising edge of the clock input. The RB7 pin will go into
output mode on the second rising clock edge, and it will
revert back to input mode (hi-impedance) after the 16th
rising edge. A timing diagram of this command is
shown in Figure 5-2.
2.3.1.5
BULK ERASE PROGRAM MEMORY
To perform a bulk erase of the program memory, the
following sequence must be performed.
1.
2.
3.
4.
Do a “Load Data All 1’s” command.
Do a “Bulk Erase User Memory” command.
Do a “Begin Programming” command.
Wait 10 ms to complete bulk erase.
If the address is pointing to the test program memory
(0x2000 - 0x200F), then both the user memory and the
test memory will be erased. The configuration word will
not be erased, even if the address is pointing to location 0x2007.
If the address is pointing to the test program memory
(0x2000 - 0x200F), then both the user memory and the
test memory will be erased. The configuration word will
not be erased, even if the address is pointing to location 0x2007.
2.3.1.9
BULK ERASE DATA MEMORY
To perform a bulk erase of the data memory, the following sequence must be performed.
1.
2.
3.
4.
Do a “Load Data All 1’s” command.
Do a “Bulk Erase Data Memory” command.
Do a “Begin Programming” command.
Wait 10 ms to complete bulk erase.
2.4
Programming Algorithm Requires
Variable VDD
READ DATA FROM DATA MEMORY
After receiving this command, the chip will transmit
data bits out of the data memory starting with the second rising edge of the clock input. The RB7 pin will go
into output mode on the second rising edge, and it will
revert back to input mode (hi-impedance) after the 16th
rising edge. As previously stated, the data memory is 8bits wide, and therefore, only the first 8-bits that are
output are actual data.
2.3.1.6
2.3.1.8
INCREMENT ADDRESS
The PIC16C84 uses an intelligent algorithm. The algorithm calls for program verification at VDD (min.) as well
as VDD (max.). Verification at VDD (min.) guarantees
good “erase margin”. Verification at VDD (max) guarantees good “program margin”.
The actual programming must be done with VDD in the
VDDP range (4.5 - 5.5V).
VDDP
= VCC range required during programming.
VDD min. = minimum operating VDD spec for the part.
VDD max.= maximum operating VDD spec for the part.
The PC is incremented when this command is
received. A timing diagram of this command is shown
in Figure 5-3.
2.3.1.7
BEGIN PROGRAMMING
A load command must be given before every begin programming command. Programming of the appropriate
memory (test program memory, user program memory
or data memory) will begin after this command is
received and decoded. An internal timing mechanism
executes an erase before write. The user must allow
10ms for programming to complete. No “end programming” command is required.
 1996 Microchip Technology Inc.
Programmers must verify the PIC16C84 at its specified
VDD max. and VDD min. levels. Since Microchip may
introduce future versions of the PIC16C84 with a
broader VDD range, it is best that these levels are user
selectable (defaults are ok).
Note:
Any programmer not meeting these
requirements may only be classified as
“prototype” or “development” programmer
but not a “production” quality programmer.
DS30190D-page 7
PIC16C84
3.0
CONFIGURATION WORD
The PIC16C84 has five configuration bits. These bits
can be set (reads '0') or left unchanged (reads '1') to
select various device configurations.
FIGURE 3-1:
Bit
Number:
CONFIGURATION WORD BIT MAP
13
12
11
10
9
8
7
6
5
4
—
—
—
—
—
—
—
—
—
CP
bit 4:
CP, Code Protection Configuration Bit
1 = code protection off
0 = code protection on
bit 3:
PWRTE, Power Up Timer Enable Configuration Bit
1 = Power up timer enabled
0 = Power up timer disabled
3
2
1
0
PWRTE WDTE FOSC1 FOSC0
bit 3-2: WDTE, WDT Enable Configuration Bits
1 = WDT enabled
0 = WDT disabled
bit 1-0
FOSC<1:0>, Oscillator Selection Configuration Bits
11: RC oscillator
10: HS oscillator
01: XT oscillator
00: LP oscillator
DS30189D-page 8
 1996 Microchip Technology Inc.
EEPROM Memory Programming Specification
4.0
CODE PROTECTION
Procedure to disable code protect:
For PIC16C84 devices, once code protection is
enabled, all program memory locations read out in a
scrambled fashion. The ID locations and the configuration word also read out in a scrambled fashion. Further
programming is disabled for the entire program memory as well as data memory. It is possible to program
the ID locations and the configuration word.
4.1
Disabling Code-Protection
It is recommended that the following procedure be performed before any other programming is attempted. It
is also possible to turn code protection off (code protect
bit = 1) using this procedure; however, all data within
the program memory and the data memory will be
erased when this procedure is executed, and thus,
the security of the data or code is not compromised.
4.2
a)
b)
c)
d)
e)
f)
g)
h)
Execute load configuration (with a '1' in bit 4,
code protect).
Increment to configuration word location (0x2007)
Execute command (000001)
Execute command (000111)
Execute 'Begin Programming' (001000)
Wait 10ms
Execute command (000001)
Execute command (000111)
Embedding Configuration Word and ID Information in the Hex File
To allow portability of code, the programmer is required to read the configuration word and ID locations from the hex
file when loading the hex file. If configuration word information was not present in the hex file then a simple warning
message may be issued. Similarly, while saving a hex file, all configuration word and ID information must be included.
An option to not include this information may be provided.
Specifically for the PIC16C84, the EEPROM data memory should also be embedded in the hex file (see Section 5.1).
Microchip Technology Inc. feels strongly that this feature is important for the benefit of the end customer.
TABLE 4-1:
CONFIGURATION WORD
PIC16C84
To code protect: XXXXXXXX0XXX
Program Memory Segment
Configuration Word (0x2007)
All memory.
ID Locations [0x2000 : 0x2003]
R/W in Protected Mode
Read Scrambled, Write Enabled
Read Scrambled, Write Disabled
Read Scrambled, Write Enabled
R/W in Unprotected Mode
Read Unscrambled, Write Enabled
Read Unscrambled, Write Enabled
Read Unscrambled, Write Enabled
Legend: X = Don’t care
 1996 Microchip Technology Inc.
DS30189D-page 9
PIC16C84
4.3
Checksum
4.3.1
CHECKSUM CALCULATIONS
The checksum is calculated by summing the following:
• The contents of all program memory locations
• The configuration word, appropriately masked
• Masked ID locations (when applicable)
The least significant 16 bits of this sum is the checksum.
The following table describes how to calculate the
checksum for each device. Note that the checksum calculation differs depending on the code protect setting.
Since the program memory locations read out differently depending on the code protect setting, the table
describes how to manipulate the actual program memory values to simulate the values that would be read
from a protected device. When calculating a checksum
by reading a device, the entire program memory can
simply be read and summed. The configuration word
and ID locations can always be read.
Note that some older devices have an additional value
added in the checksum. This is to maintain compatibility with older device programmer checksums.
TABLE 4-2:
Device
CHECKSUM COMPUTATION
Code
Protect
PIC16C84
OFF
ON
Checksum*
SUM[0x000:0x3FF] + CFGW & 0x1F + 0x3FE0
SUM_XNOR7[0x000:0x3FF] + (CFGW & 0x1F | 0x60)
Blank
Value
0x25E6 at
0 and max
address
0x3BFF
0xFC6F
0x07CD
0xFC15
Legend: CFGW = Configuration Word
SUM[a:b] = [Sum of locations a to b inclusive]
SUM_XNOR7[a:b] = XNOR of the seven high order bits of memory location with the seven low order bits summed over
locations a through b inclusive. For example, location_a = 0x123 and location_b = 0x456, then
SUM_XNOR7 [location_a : location_b] = 0x001F.
*Checksum = [Sum of all the individual expressions] MODULO [0xFFFF]
DS30189D-page 10
 1996 Microchip Technology Inc.
EEPROM Memory Programming Specification
5.0
PROGRAM/VERIFY MODE ELECTRICAL CHARACTERISTICS
5.1
Embedding Data EEPROM Contents in Hex File
The programmer should be able to read data EEPROM information from a hex file and conversely (as an option) write
data EEPROM contents to a hex file along with program memory information and fuse information.
The 64 data memory locations are logically mapped starting at address 0x2100. The format for data memory storage is
one data byte per address location, lsb aligned.
TABLE 5-1:
AC/DC CHARACTERISTICS
TIMING REQUIREMENTS FOR PROGRAM/VERIFY TEST MODE
Standard Operating Conditions
Operating Temperature
+10°C ≤ TA ≤ +40°C, unless otherwise stated,
(25°C is recommended)
Operating Voltage
4.5V ≤ VDD ≤ 5.5V, unless otherwise stated.
Characteristic
Sym.
Min.
Typ.
Max.
Units Conditions/Comments
Supply voltage during programming
VDDP
4.5
5.0
5.5
V
Supply voltage during verify
VDDV
VDD min.
VDD max.
V
Note 1
High voltage on MCLR for test mode entry
VIHH
12
14.0
V
Note 2
Supply current (from VDD) during program/verify
IDDP
50
mA
Supply current from VIHH (on MCLR)
IHH
200
µA
MCLR rise time (VSS to VHH) for test mode
entry
tvHHR
1.0
µs
(RB6, RB7) input high level
VIH1
0.8 VDD
V
Schmitt Trigger input
(RB6, RB7) input low level MCLR (test
mode selection
VIL1
0.2 VDD
V
Schmitt Trigger input
RB6, RB7 setup time (before pattern
setup time)
tset0
100
ns
Data in setup time before clock ↓
tset1
100
ns
Data in hold time after clock ↓
thld1
100
ns
Data input not driven to next clock input
(delay required between command/data or
command/command)
tdly1
1.0
µs
Delay between clock ↓ to clock ↑ of next
command or data
tdly2
1.0
µs
Clock to data out valid (during read data)
tdly3
80
ns
Note 1: Program must be verified at the minimum and maximum VDD limits for the part.
Note 2: VIHH must be higher than VDD + 4.5V to stay in programming/verify mode.
 1996 Microchip Technology Inc.
DS30189D-page 11
PIC16C84
FIGURE 5-1:
LOAD DATA FOR PROGRAM MEMORY COMMAND (SERIAL PROGRAM/VERIFY)
VIHH
MCLR
100ns
tset0
thld0
1
2
3
4
5
6
100ns
0
0
0
0
tdly2
1µs min. 1
2
3
4
5
15
16
RB6
(CLOCK)
RB7
(DATA)
0
1
0
tdly1
tset1
0
tset1
1µs min.
thld1
thld1
100ns
min.
100ns
min.
Program/Verify Test Mode
Reset
FIGURE 5-2:
READ DATA FROM PROGRAM MEMORY COMMAND (SERIAL PROGRAM/VERIFY)
VIHH
MCLR
tset0
thld0
1
2
3
4
5
6
0
0
1
0
0
0
tdly2
1µs min. 1
2
3
4
5
15
16
RB6
(CLOCK)
tdly3
RB7
(DATA)
tdly1
tset1
1µs min.
thld1
100ns
min.
RB7 = input
RB7
input
RB7 = output
Program/Verify Test Mode
Reset
FIGURE 5-3:
INCREMENT ADDRESS COMMAND (SERIAL PROGRAM/VERIFY)
VIHH
MCLR
1
2
3
4
5
6
1
1
0
0
0
tdly2
1µs min.
1
Next Command
2
RB6
(CLOCK)
RB7
(DATA)
0
tset1
thld1
0
0
tdly1
1µs min.
100ns
min.
Reset
DS30189D-page 12
Program/Verify Test Mode
 1996 Microchip Technology Inc.
EEPROM Memory Programming Specification
NOTES:
 1996 Microchip Technology Inc.
DS30190D-page 13
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5/10/96
All rights reserved.  1996, Microchip Technology Incorporated, USA.
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rights arising from such use or otherwise. Use of Microchip’s products as critical components in life support systems is not authorized except with express written approval by Microchip.
No licenses are conveyed, implicitly or otherwise, under any intellectual property rights. The Microchip logo and name are registered trademarks of Microchip Technology Inc. All rights
reserved. All other trademarks mentioned herein are the property of their respective companies.
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 1996 Microchip Technology Inc.