AD ADUC842BCP

PRELIMINARY TECHNICAL DATA
a
®
ADuC842 MicroConverter , 12- Bit ADCs and DACs
with Embedded Hi-Speed 62KB FLASH MCU
Preliminary Technical Data
FEATURES
PIN COMPATABLE
Upgrade to ADuC812/ADuC832
INCREASED PERFORMANCE
Single Cycle 16MIPS 8052 core
High Speed 400kSPS 12-Bit ADC
INCREASED MEMORY
62Kbytes On-Chip Flash/EE Program Memory
4KBytes On-Chip Flash/EE Data Memory
In circuit re-programmable
Flash/EE, 100 Yr Retention, 100 Kcycles Endurance
2304 Bytes On-Chip Data RAM
SMALLER PACKAGE
Available in 8mm x 8mm Chip Scale Package
Also available in 52 pin PQFP - pin compatable with
ADuC812/ADuC831
ANALOG I/O
8-Channel, 400kSPS High Accuracy, 12-Bit ADC
On-Chip, 20 ppm/ o C Voltage Reference
DMA Controller, High-Speed ADC-to-RAM capture
Two 12-Bit Voltage Output DACs
Dual Output PWM-SD DACs
On-Chip Temperature Monitor Function
8051 Based Core
8051-Compatible Instruction Set (16.7 MHz Max)
High performance Single Cycle Core*
32kHz Ext Crystal,On-Chip Programmable-PLL
12 Interrupt Sources, Two Priority Levels
Dual Data Pointers, Extended 11-bit Stack Pointer
On-Chip Peripherals
Time Interval Counter (TIC)
UART, I2C and SPI ® Serial I/O
Watchdog Timer (WDT),
Power Supply Monitor (PSM)
Power
Normal: 6mA @ 5 V (Core CLK = 2.098 MHz)
Power-Down: 15µA @ 3 V
Development Tools
Low Cost, comprehensive development system
incorporating non-intrusive single pin emulation
IDE based, assembly and C source debug
APPLICATIONS
Optical Networking - Laser Power Control
Basestation Systems
Precision Instrumentation, Smart Sensors
Transient Capture Systems
DAS and Communications Systems
MicroConverter is a registered trademark of Analog Devices, Inc.
SPI is a registered trademark of Motorola Inc.
* 68% of insturctions completed in one or two clock cycles
REV. PrB
Information furnished by Analog Devices is believed to be accurate and
reliable. However, no responsibility is assumed by Analog Devices for its
use, nor for any infringements of patents or other rights of third parties
which may result from its use. No license is granted by implication or
otherwise under any patent or patent rights of Analog Devices.
ADuC842
FUNCTIONAL
BLOCK
DIAGRAM
ADuC842
A D C0
A D C1
.
.
.
T/H
4 0 0 K SP S
12 -B IT A D C
MU X
H AR D W AR E
C AL IBR A TIO N
A D C6
A D C7
D AC
12-BI T
DAC
BU F
D AC
16-BIT
Σ ∆ DAC
P WM 0
MU X
16-BIT
PWM
PW M1
16-BIT
PWM
TEM P
S EN SO R
16 MIP S 8 0 51 -B AS ED MC U WITH AD D IT IO NA L
PE RIP H ER AL S
6 2 K BY TES FL A SH /EE PR O GR AM M EMO RY
4 KB YTES FLA SH /E E DA TA MEM O R Y
2 3 04 BY TE S US ER R AM
P LL
VR E F
BU F
16-BIT
Σ ∆ DAC
A D C5
IN TE R N AL
BA N DG AP
V R EF
12-BI T
DAC
3 × 1 6 B IT TIM ER S
1 × R E AL TIM E C L O C K
PO W ER S UP PL Y M O N
WA TC H DO G TIME R
4 × P AR A L LE L
P O R TS
U A RT , I2 C AN D SPI
S ER IA L I/O
OSC
X TAL 1
XT AL 2
GENERAL DESCRIPTION
The ADuC842 is a complete smart transducer front-end, integrating a high-performance self calibrating multichannel ADC,
dual DAC and an optimized single cycle 16MHz 8-bit
MCU(8051 instruction set compatible) on a single chip.
The device operates from a 32 kHz crystal with an on-chip PLL
generating a high-frequency clock of 16.77MHz. This clock is,
in turn, routed through a programmable clock divider from
which the MCU core clock operating frequency is generated.
The microcontroller is an optimized 8052 core offering up to 16
MIPS peak performance. 62 Kbytes of nonvolatile Flash/EE
program memory are provided on-chip. 4 Kbytes of nonvolatile
Flash/EE data memory, 256 bytes RAM and 2 KBytes of extended RAM are also integrated on-chip.
The ADuC842 also incorporates additional analog functionality
with two 12-bit DACs, power supply monitor, and a bandgap
reference. On-chip digital peripherals include two 16-bit Σ∆
DACs, dual output 16-bit PWM, watchdog timer, time interval
counter, three timers/counters, and three serial I/O ports (SPI,
I2C and UART).
On the ADuC812 and ADuC832 the I2C and SPI interfaces
shared some of the same pins. For backwards compatability
this is also the case for the ADuC842. However, there is also
the option to allow SPI operate separately on P3.3, P3.4 and
P3.5 while I2C uses the standard pins. The I2C interface has
also been enhanced to offer repeated start, general call and
quad addressing.
On-chip factory firmware supports in-circuit serial download and
debug modes (via UART), as well as single-pin emulation mode
via the EA pin. A functional block diagram of the ADuC842 is
shown above.
The part is specified for 3V and 5V operation with a maximum
operating frequency of 16.777MHz.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A
Tel: 781/329-4700
www.analog.com
Fax: 781/326-8703
© Analog Devices, Inc., 2003
PRELIMINARY TECHNICAL DATA
1
(AV
ADuC842–SPECIFICATIONS
to 5.5V. V
= 2.5 V Internal Reference, Fcore = 16.777 MHz, All specifications T = T
= DVDD = 2.7V to 3.3V or 4.5V
Parameter
Test Conditions/Comments
DD
REF
A
VDD = 5 V
VDD = 3 V
Unit
12
±1
±0.3
±0.9
±0.25
±1.5
+1.5/-0.9
1
12
±1
±0.3
±0.9
±0.25
±1.5
+1.5/-0.9
1
Bits
LSB
LSB
LSB
LSB
LSB
LSB
LSB
±2
±1
±2
–85
±3
±1
±3
–85
LSB max
LSB typ
LSB max
dB typ
MIN to TMAX, unless otherwise noted.)
ADC CHANNEL SPECIFICATIONS
DC ACCURACY 2,3
Resolution
Integral Nonlinearity
Differential Nonlinearity
Integral Nonlinearity 9
Differential Nonlinearity 9
Code Distrbution
CALIBRATED ENDPOINT ERRORS4,5
Offset Error
Offset Error Match
Gain Error
Gain Error Match
fSAMPLE = 147 kHz,
max
typ
max
typ
max
max
typ
DYNAMIC PERFORMANCE
Signal-to-Noise Ratio (SNR) 6
Total Harmonic Distortion (THD)
Peak Harmonic or Spurious Noise
Channel-to-Channel Crosstalk 7
2.5V Internal Reference
1V External Reference
1V External Reference
ADC Input is a DC Voltage
fIN = 10 kHz Sine Wave
fSAMPLE = 147 kHz
71
–85
–85
–80
71
–85
–85
–80
dB
dB
dB
dB
ANALOG INPUT
Input Voltage Ranges
Leakage Current
Input Capacitance
0 to VREF
±1
32
0 to VREF
±1
32
Volts
µA max
pF typ
TEMPERATURE SENSOR 8
Voltage Output at 25°C
Voltage TC
Accuracy
Accuracy
650
–2.0
±3
±1.5
650
–2.0
±3
±1.5
mV typ
mV/°C typ
°C typ
°C typ
typ
typ
typ
typ
DAC CHANNEL SPECIFICATIONS
Internal Buffer Enabled
DC ACCURACY 10
Resolution
Relative Accuracy
Differential Nonlinearity 11
2.5V Internal Reference
Internal 2.5V VREF
External 2.5V V REF
DAC Load to AGND
RL = 10kΩ, CL = 100 pF
±50
±1
±1
0.5
12
±3
-1
±1/2
±50
±1
±1
0.5
Bits
LSB typ
LSB max
±1/2
mV max
% max
% typ
% typ
ANALOG OUTPUTS
Voltage Range_0
Voltage Range_1
Output Impedance
I SINK
0 to VREF
0 to VDD
0.5
50
0 to VREF
0 to VDD
0.5
50
V typ
V typ
Ω typ
µA typ
DAC VREF = 2.5V
DAC VREF = VDD
DAC AC CHARACTERISTICS
Voltage Output Settling Time
15
15
µs typ
10
10
nV sec typ
Full-Scale Settling Time to
Within 1/2 LSB of Final Value
1 LSB Change at Major Carry
Offset Error
Gain Error
Gain Error
Mismatch
Digital-to-Analog Glitch Energy
12
±3
-1
–2–
Guaranteed 12-Bit Monotonic
LSB typ
V REF Range
AV DD Range
VREF Range
% of Full-Scale on DAC1
REV. PrB
PRELIMINARY TECHNICAL DATA
ADuC842
Parameter
VDD = 5 V
VDD = 3 V
Unit
12
±3
-1
±1/2
±10
±1
0.5
12
±3
-1
±1/2
±10
±1
0.5
Bits
LSB typ
LSB max
LSB typ
mV max
% typ
% typ
V REF Range
VREF Range
% of Full-Scale on DAC1
ANALOG OUTPUTS
Voltage Range_0
0 to VREF
0 to VREF
V typ
DAC VREF = 2.5V
REFERENCE INPUT/OUTPUT
REFERENCE OUPUT 14
Output Voltage (VREF)
Accuracy
Power Supply Rejection
Reference Temperature Coefficient
Internal VREF Power-On Time
2.5
±2.5
47
±20
80
2.5
±2.5
57
±20
80
V
% max
dB typ
ppm/°C typ
ms typ
0.1
V DD
20
10
0.1
V DD
20
10
V min
V max
kΩ typ
µA max
DAC CHANNEL SPECIFICATIONS
Internal Buffer Disabled
DC ACCURACY 10
Resolution
Relative Accuracy
Differential Nonlinearity 11
Offset Error
Gain Error
Gain Error Mismatch
EXTERNAL REFERNCE INPUT 15
Voltage Range (V REF)9
Input Impedance
Input Leakage
Test Conditions/Comments
12,13
Guaranteed 12-Bit Monotonic
Of VREF measured at the CREF pin
Internal Band Gap Deselected via
ADCCON1.6
POWER SUPPLY MONITOR (PSM)
DVDD Trip Point Selection Range
DVDD Power Supply Trip Point
Accuracy
WATCH DOG TIMER (WDT)
Time-out Period
2.63
4.37
Vmin
Vmax
±3.5
% max
9
0
2000
FLASH/EE MEMORY RELIABILITY
CHARACTERISTICS 16
Endurance17
100,000
Data Retention18
100
DIGITAL INPUTS
Input High Voltage (VINH)
2.4
Input Low Voltage (VINL)
0.8
Input Leakage Current (Port 0,1, EA) ±10
±1
Logic 1 Input Current
(All Digital Inputs)
±10
±1
Logic 0 Input Current (Port 2, 3)
–80
–40
Logic 1-0 Transition Current (Port 2, 3) –700
–400
CRYSTAL OSCILLATOR
Logic Inputs, XTAL1 Only
VINL, Input Low Voltage
VINH, Input High Voltage
REV. PrB
Four Trip Points Selectable in
This Range Programmed via
TPD1–0 in PSMCON
0.8
3.5
0
2000
100,000
100
±1
±1
–40
–400
0.4
2.5
–3–
ms min
ms max.
Nine Time-out Periods
Selectable in This Range
Cycles min
Years min
V min
V max
µA max
µA typ
µA
µA
µA
µA
µA
µA
max
typ
max
typ
max
typ
V typ
V typ
VIN = 0 V or VDD
VIN = 0 V or VDD
VIN = VDD
VIN = VDD
VIL = 0 V
VIL = 2 V
VIL = 2 V
PRELIMINARY TECHNICAL DATA
ADuC842–SPECIFICATIONS1
Parameter
V DD =5V
XTAL1 Input Capacitance
XTAL2 Output Capacitance
18
18
18
18
pF typ
pF typ
MCU Clock Rate
16.777216
16.777216
MHz max
DIGITAL OUTPUTS
Output High Voltage (VOH)
2.4
2.4
V min
4.0
2.6
V typ
0.4
0.2
0.4
0.4
0.4
0.2
0.4
0.4
V max
V typ
Vmax
Vmax
±10
±1
10
±10
±1
10
µA max
µA typ
pF typ
500
100
ms typ
µs typ
400
400
400
3
3
ms
ms
ms
ms
ms
typ
typ
typ
typ
typ
2.7
3.3
V
V
V
V
min.
max.
min.
max.
Output Low Voltage (VOL)
ALE, Ports 0 and 2
Port 3
SCLOCK/SDATA
Floating State Leakage Current
Floating State Output Capacitance
START UP TIME
At Power-On
500
From Idle Mode
100
From Power-Down Mode
Wakeup with INT0 Interrupt
150
150
Wakeup with SPI/I2C Interrupt
Wakeup with External RESET
150
After External RESET in Normal Mode 3
After WDT Reset in Normal Mode 3
POWER REQUIREMENTS
Power Supply Voltages
AVDD / DVDD - AGND
V DD =3V
Units
Test Conditions
VDD = 4.5 V
ISOURCE = 80
VDD = 2.7 V
ISOURCE = 20
ISINK
ISINK
ISINK
ISINK
=
=
=
=
to 5.5 V
µA
to 3.3 V
µA
1.6 mA
1.6 mA
4 mA
8 mA
Core CLK = 16MHz
Controlled via WDCON SFR
19,20
4.5
5.5
Power Supply Currents Normal Mode
DVDD Current9
AVDD Current9
DVDD Current
AVDD Current
Power Supply Currents Idle Mode
DVDD Current9
AVDD Current9
DVDD Current9
AVDD Current9
AVDD / DVDD = 5V nom.
12
1.4
25
21
1.4
6
1.4
n/a
n/a
n/a
mA
mA
mA
mA
mA
typ
max
max
typ
max
Fcore = 8 MHz (CD=3)
5
0.11
11
10
0.11
2.5
0.11
n/a
n/a
n/a
mA
mA
mA
mA
mA
typ
typ
max
typ
typ
Fcore = 8 MHz (CD=3)
2.5
15
12
120
uA
uA
uA
uA
Power Supply Currents Power Down Mode
3
AVDD Current
DVDD Current
35
25
120
Typical Additional Power Supply Currents
PSM Peripheral
ADC
DAC
AVDD / DVDD = 3V nom.
Fcore = 16 MHz (CD=0)
Fcore =16 MHz (CD=0)
For any Core CLK
typ
max
typ
typ
osc off
osc on
AVDD = DVDD = 5V
50
1.5
150
uA typ
mA typ
uA typ
–4–
REV. PrB
PRELIMINARY TECHNICAL DATA
ADuC842
NOTES
1
Temperature Range -40ºC to +85ºC.
2
ADC Linearity is guaranteed during normal MicroConverter Core operation.
3
ADC LSB Size = Vref / 2^12 i.e for Internal Vref=2.5V, 1LSB = 610uV and for External Vref =1V, 1LSB = 244uV.
4
Offset and Gain Error and Offset and Gain Error Match are measured after factory calibration.
5
Based on external ADC system components the user may need to execute a system calibration to remove additional external channel errors
and achieve these specifications.
6
SNR calculation includes distortion and noise components.
7
Channel to Channel Crosstalk is measured on adjacent channels.
8
The Temperature Monitor will give a measure of the die temperature directly, air temperature can be inferred from this result.
9
These numbers are not production tested but are guaranteed by Design and/or Characterization data on production release.
10
DAC linearity is calculated using :
reduced code range of 48 to 4095, 0 to Vref range.
reduced code range of 48 to 3945, 0 to V DD range.
DAC Output Load = 10K Ohms and 100 pF.
11
DAC Differential NonLinearity specified on 0 to Vref and 0 to Vdd ranges
12
DAC specification for output impedance in the unbuffered case depends on DAC code
13
DAC specifications for Isink, voltage output settling time and digital-to-analog glitch engergy depend on external buffer implementation in
unbuffered mode.
14
Measured with Vref and Cref pins decoupled with 0.1µF capacitors to graound. Power-up time for the Internal Reference will be determined
by the value of the decoupling capacitor chosen for both the Vref and Cref pins.
15
When using an External Reference device, the internal bandgap reference input can be bypassed by setting the ADCCON1.6 bit. In this
mode the Vref and Cref pins need to be shorted together for correct operation.
16
Flash/EE Memory Reliability Characteristics apply to both the Flash/EE program memory and the Flash/EE data memory.
17
Endurance is qualified to 100 Kcycles as per JEDEC Std. 22 method A117 and measured at -40ºC, +25ºC, and +85ºC, typical endurance at
25ºC is 700 Kcycles.
18
Retention lifetime equivalent at junction temperature (Tj) = 55ºC as per JEDEC Std. 22 method A117. Retention lifetime based on an
activation energy of 0.6eV will derate with junction temperature as shown in Figure 27 in the Flash/EE Memory description section of this
data sheet.
19
Power Supply current consumption is measured in Normal, Idle, and Power-Down Modes under the following conditions:
Normal Mode:
Reset = 0.4 V, Digital I/O pins = open circuit, Core Clk changed via CD bits in PLLCON, Core Executing internal
software loop.
Idle Mode:
Reset = 0.4 V, Digital I/O pins = open circuit, Core Clk changed via CD bits in PLLCON, PCON.0=1, Core
Execution suspended in idle mode.
Power-Down Mode: Reset = 0.4 V, All Port 0 pins = 0.4 V, All other digital I/O and Port 1 pins are open circuit, Core Clk changed
via CD bits in PLLCON, PCON.0=1, Core Execution suspended inpower-down mode, OSC turned ON or OFF via
OSC_PD bit (PLLCON.7) in PLLCON SFR
20
D VDD power supply current will increase typically by 3 mA (3 V operation) and 10 mA (5 V operation) during a Flash/EE memory program
or erase cycle.
Specifications subject to change without notice.
REV. PrB
–5–
PRELIMINARY TECHNICAL DATA
ADuC842
ABSOLUTE MAXIMUM RATINGS*
(T A = 25°C unless otherwise noted)
AVDD to DV DD . . . . . . . . . . . . . . . . . . –0.3 V to +0.3 V
AGND to DGND . . . . . . . . . . . . . . . . . –0.3 V to +0.3 V
DVDD to DGND, AVDD to AGND . . . . –0.3 V to +7 V
Digital Input Voltage to DGND –0.3 V, DVDD + 0.3 V
Digital Output Voltage to DGND –0.3 V, DVDD + 0.3 V
VREF to AGND . . . . . . . . . . . . . . . –0.3 V, AVDD + 0.3 V
Analog Inputs to AGND . . . . . . . –0.3 V, AVDD + 0.3 V
Operating Temperature Range Industrial ADuC842BS
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –40°C to +85°C
Operating Temperature Range Industrial ADuC842BCP
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –40°C to +85°C
Storage Temperature Range . . . . . . . . –65°C to +150°C
Junction Temperature . . . . . . . . . . . . . . . . . . . . . . . . 150°C
θJA Thermal Impedance (ADuC831BS) . . . . . . . 90°C/W
θJA Thermal Impedance (ADuC831BCP) . . . . . 52°C/W
Lead Temperature, Soldering
Vapor Phase (60 sec) . . . . . . . . . . . . . . . . . . . . . . . 215°C
Infrared (15 sec) . . . . . . . . . . . . . . . . . . . . . . . . . . 220°C
*Stresses above those listed under Absolute Maximum Ratings may
cause permanent damage to the device. This is a stress rating only;
functional operation of the device at these or any other conditions above
those listed in the operational sections of this specification is not implied.
Exposure to absolute maximum rating conditions for extended periods
may affect device reliability.
ORDERING GUIDE
Model
Temperature
Range
Package
Description
Package
Option
ADuC842BS
ADuC842BCP
–40°C to +85°C
–40°C to +85°C
52-Lead Plastic Quad Flatpack
56-Lead Chip Scale Package
S-52
CP-56
CAUTION
ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily
accumulate on the human body and test equipment and can discharge without detection.
Although the ADuC842 features proprietary ESD protection circuitry, permanent damage may
occur on devices subjected to high energy electrostatic discharges. Therefore, proper ESD
precautions are recommended to avoid performance degradation or loss of functionality.
–6–
Rev.PrB
PRELIMINARY TECHNICAL DATA
ADuC842
PIN FUNCTION DESCRIPTIONS
Mnemonic
Type Function
D V DD
A V DD
C REF
V REF
P
P
I
I/O
AGND
P1.0–P1.7
G
I
ADC0–ADC7 I
T2
I
T2EX
I
SS
SDATA
SCLOCK
MOSI
MISO
DAC0
DAC1
RESET
I
I/O
I/O
I/O
I/O
O
O
I
P3.0–P3.7
I/O
PWMC
PWM0
PWM1
RxD
TxD
INT0
I
O
O
I/O
O
I
INT1
I
T0
T1
CONVST
I
I
I
WR
O
RD
XTAL2
XTAL1
DGND
P2.0–P2.7
(A8–A15)
O
O
I
G
I/O
(A16–A23)
REV. PrB
Digital Positive Supply Voltage, 3 V or 5 V Nominal
Analog Positive Supply Voltage, 3 V or 5 V Nominal
Decoupling Input for On-Chip Reference. Connect 0.1 µF between this pin and AGND.
Reference Input/Output. This pin is connected to the internal reference through a series resistor
and is the reference source for the analog-to-digital converter. The nominal internal reference
voltage is 2.5 V and this appears at the pin. This pin can be overdriven by an external reference.
Analog Ground. Ground Reference point for the analog circuitry.
Port 1 is an 8-bit Input Port only. Unlike other Ports, Port 1 defaults to Analog Input Mode, to
configure any of these Port Pins as a digital input, write a “0” to the port bit. Port 1 pins are multifunction and share the following functionality.
Analog Inputs. Eight single-ended analog inputs. Channel selection is via ADCCON2 SFR.
Timer 2 Digital Input. Input to Timer/Counter 2. When Enabled, Counter 2 is incremented in
response to a 1 to 0 transition of the T2 input.
Digital Input. Capture/Reload trigger for Counter 2 and also functions as an Up/Down control
input for Counter 2.
Slave Select Input for the SPI Interface
User Selectable, I2C-Compatible or SPI Data Input/Output Pin
Serial Clock Pin for I2C-Compatible or SPI Serial Interface Clock
SPI Master Output/Slave Input Data I/O Pin for SPI Interface
SPI Master Input/Slave Output Data I/O Pin for SPI Serial Interface
Voltage Output from DAC0
Voltage Output from DAC1
Digital Input. A high level on this pin for 24 master clock cycles while the oscillator is running
resets the device.
Port 3 is a bidirectional port with internal pull-up resistors. Port 3 pins that have 1s written to
them are pulled high by the internal pull-up resistors, and in that state they can be used as inputs.
As inputs Port 3 pins being pulled externally low will source current because of the internal pullup resistors. Port 3 pins also contain various secondary functions which are described below.
PWM Clock Input
PMW0 Voltage Output. PWM outputs can be configured to use ports 2.6 & 2.7 or 3.4 and 3.3
PMW1 Voltage Ouput.
See CFG832 Register for further Information.
Receiver Data Input (Asynchronous) or Data Input/Output (Synchronous) of Serial (UART) Port
Transmitter Data Output (Asynchronous) or Clock Output (Synchronous) of Serial (UART) Port
Interrupt 0, programmable edge or level triggered Interrupt input, which can be programmed to
one of two priority levels. This pin can also be used as a gate control input to Timer 0.
Interrupt 1, programmable edge or level triggered Interrupt input, which can be programmed to
one of two priority levels. This pin can also be used as a gate control input to Timer 1.
Timer/Counter 0 Input
Timer/Counter 1 Input
Active low Convert Start Logic input for the ADC block when the external Convert start function is enabled.
A low-to-high transition on this input puts the track/hold into its hold mode and starts conversion.
Write Control Signal, Logic Output. Latches the data byte from Port 0 into the external data
memory.
Read Control Signal, Logic Output. Enables the external data memory to Port 0.
Output of the Inverting Oscillator Amplifier
Input to the inverting oscillator amplifier and input to the internal clock generator circuits.
Digital Ground. Ground reference point for the digital circuitry.
Port 2 is a bidirectional port with internal pull-up resistors. Port 2 pins that have 1s written to them are
pulled high by the internal pull-up resistors, and in that state they can be used as inputs. As inputs
Port 2
pins being pulled externally low will source current because of the internal pull-up resistors. Port 2
emits the high order address bytes during fetches from external program memory and middle and
high order address bytes during accesses to the external 24-bit external data memory space.
–7–
PRELIMINARY TECHNICAL DATA
ADuC842
PIN FUNCTION DESCRIPTION (continued)
Mnemonic
Type Function
PSEN
O
ALE
O
EA
I
P0.7–P0.0
I/O
Program Store Enable, Logic Output. This output is a control signal that enables the external
program memory to the bus during external fetch operations. It is active every six oscillator
periods except during external data memory accesses. This pin remains high during internal
program execution. PSEN can also be used to enable serial download mode when pulled low
through a resistor on power-up or RESET.
Address Latch Enable, Logic Output. This output is used to latch the low byte (and page byte for
24-bit address space accesses) of the address into external memory during normal operation.
External Access Enable, Logic Input. When held high, this input enables the device to fetch code
from internal program memory locations 0000H to 1FFFH. When held low this input enables the
device to fetch all instructions from external program memory. This pin should not be left float.
Port 0 is an 8-Bit Open Drain Bidirectional I/O port. Port 0 pins that have 1s written to them
float and in that state can be used as high impedance inputs. Port 0 is also the multiplexed low
order address and data bus during accesses to external program or data memory. In this
application it uses strong internal pull-ups when emitting 1s.
TERMINOLOGY
ADC SPECIFICATIONS
Integral Nonlinearity
This is the maximum deviation of any code from a straight
line passing through the endpoints of the ADC transfer
function. The endpoints of the transfer function are zero
scale, a point 1/2 LSB below the first code transition and
full scale, a point 1/2 LSB above the last code transition.
amplitude of the fundamental. Noise is the rms sum of all
nonfundamental signals up to half the sampling frequency
(fS/2), excluding dc. The ratio is dependent upon the
number of quantization levels in the digitization process;
the more levels, the smaller the quantization noise. The
theoretical signal to (noise +distortion) ratio for an ideal
N-bit converter with a sine wave input is given by:
Signal to (Noise + Distortion) = (6.02N + 1.76) dB
Differential Nonlinearity
Thus for a 12-bit converter, this is 74 dB.
This is the difference between the measured and the ideal
1 LSB change between any two adjacent codes in the
ADC.
Total Harmonic Distortion
Total Harmonic Distortion is the ratio of the rms sum of
the harmonics to the fundamental.
Offset Error
This is the deviation of the first code transition
(0000 . . . 000) to (0000 . . . 001) from the ideal, i.e., +1/2
LSB.
DAC SPECIFICATIONS
Relative Accuracy
This is the deviation of the last code transition from the
ideal AIN voltage (Full Scale – 1.5 LSB) after the offset
error has been adjusted out.
Relative accuracy or endpoint linearity is a
the maximum deviation from a straight line
through the endpoints of the DAC transfer
measured after adjusting for zero error and
ror.
Signal to (Noise + Distortion) Ratio
Voltage Output Settling Time
Gain Error
measure of
passing
function. It is
full-scale er-
This is the amount of time it takes for the output to settle
to a specified level for a full-scale input change.
This is the measured ratio of signal to (noise + distortion)
at the output of the A/D converter. The signal is the rms
Digital-to-Analog Glitch Impulse
This is the amount of charge injected into the analog output when the inputs change state. It is specified as the area
of the glitch in nV sec.
–8–
Rev.PrB
PRELIMINARY TECHNICAL DATA
ADuC842
PIN CONFIGURATION
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ADuC842
$'&
ADC
CONTROL
AND
CALIBRATION
%LW
7+
0X[
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DAC
CONTROL
12-BIT
VOLTAGE
OUTPUT DAC
DAC0
12-BIT
VOLTAGE
OUTPUT DAC
DAC1
16-BIT
⌺⌬ DAC
16-BIT
$'&
PWM
CONTROL
$'&
4 KBYTES DATA
FLASH/EE
BANDGAP
REFERENCE
2 KBytes USER XRAM
95()
%8)
2 X DATA POINTERS
11-BIT STACK POINTER
&5()
256 Bytes USER
RAM
16MIPS
8052
WATCHDOG
TIMER
MCU
CORE
POWER SUPPLY
MONITOR
PWM1
T0
16-BIT
COUNTER
TIMERS
T1
T2
,17
PROG. CLOCK
DIVIDER
,17
TIME INTERVAL
COUNTER
(WAKEUP CCT)
MISO
SCLOCK
SINGLE-PIN
EMULATOR
1
(6 $(
3
PLL
SYNCHRONOUS
SERIAL INTERFACE
(SPI OR I2C )
SDATA/MOSI
UART
TIMER
ALE
TXD
RXD
DGND
RESET
DGND
DGND
DVDD
DVDD
DVDD
AVDD
AGND
325
16-BIT
PWM
T2EX
DOWNLOADER
DEBUGGER
ASYNCHRONOUS
SERIAL PORT
(UART)
PWM0
MUX
16-BIT
PWM
62 KBYTES PROGRAM
FLASH/EE INCLUDING
USER DOWNLOAD MODE
TEMP
SENSOR
4% DAC
66
OSC
XTAL2
3
XTAL1
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Figure 1 ADuC842 Block Diagram (Shaded areas are features not present on the ADuC812)
REV. PrB
–9–
PRELIMINARY TECHNICAL DATA
ADuC842
INTRODUCTION
The ADuC842 is a 16MIPs 8052 core upgrade to the
ADuC832. It has all the same features as the ADuC832
but the standard 12-cycle 8052 core has been replaced with
a 16MIPs single cycle core.
Since the ADuC842 and ADuC832 share the same feature
set only the differneces bettween the two chips are documented here. For full documentation on the ADuC832
please consult the datasheet available at
http://www.analog.com/microconverter
8052 Instruction Set
The following pages document the number of clock cycles
required for each instruction. Most instructions are executed in one or two clock cycles resulting in a 16MIPs
peak peformance when operating at PLLCON = 00H.
Timer Operation
Timers on a standard 8052 increment by one with each
machine cycle. On the ADuC842 one machine cycle is
equal to one clock cycle hence the timers will increment at
the same rate as the core clock.
ALE
The output on the ALE pin on the ADuC832 was a clock
at 1/6th of the core operating frequency. On the ADuC842
the ALE pin operates as follows.
For a single machine cycle instruction: ALE is high for the
first half of the machine cycle and low for the second half.
The ALE output is at the core operating frequency.
For a two or more machine cycle instruction: ALE is high
for the first half of the first machine cycle and then low for
the rest of the machine cycles.
External Memory Access
There is no support for external program memory access
on the ADuC842. When accessing external RAM the
EWAIT register may need to be programmed in order to
give extra machine cycles to MOVX commands. This is to
account for differing external RAM access speeds.
Baud Rate Generation
There is an addition divide by two in the fractional divider
of the ADuC842 this means that any values calculated for
T3CON for the ADuC832 need to be incremented by one
in order to give the same baud rate on the ADuC842.
–10–
Rev.PrB
PRELIMINARY TECHNICAL DATA
ADuC842
INSTRUCTION TABLE
Mnemonic
Description
Bytes
Cycles
ADD A,Rn
Add register to A
1
1
ADD A,@Ri
Add indirect memory to A
1
2
ADD A,dir
Add direct byte to A
2
2
ADD A,#data
Add immediate to A
2
2
ADDC A,Rn
Add register to A with carry
1
1
ADDC A,@Ri
Add indirect memory to A with carry
1
2
ADDC A,dir
Add direct byte to A with carray
2
2
ADD A,#data
Add immediate to A with carry
2
2
SUBB A,Rn
Subtract register from A with borrow
1
1
SUBB A,@Ri
Subtract indirect memory from A with borrow 1
2
SUBB A,dir
Subtract direct from A with borrow
2
2
SUBB A,#data
Subtract immediate from A with borrow
2
2
INC A
Increment A
1
1
INC Rn
Increment register
1
1
INC @Ri
Increment indirect memory
1
2
INC dir
Increment direct byte
2
2
INC DPTR
Increment data pointer
1
3
DEC A
Decrement A
1
1
DEC Rn
Decrement Register
1
1
DEC @Ri
Decrement indirect memory
1
2
DEC dir
Decrement direct byte
2
2
MUL AB
Multiply A by B
1
9
DIV AB
Divide A by B
1
9
DA A
Decimal Adjust A
1
2
ANL A,Rn
AND register to A
1
1
ANL A,@Ri
AND indirect memory to A
1
2
ANL A,dir
AND direct byte to A
2
2
ANL A,#data
AND immediate to A
2
2
ANL dir,A
AND A to direct byte
2
2
ANL dir,#data
AND immediate data to direct byte
3
3
ORL A,Rn
OR register to A
1
1
ORL A,@Ri
OR indirect memory to A
1
2
ORL A,dir
OR direct byte to A
2
2
ORL A,#data
OR immediate to A
2
2
ORL dir,A
OR A to direct byte
2
2
ORL dir,#data
OR immediate data to direct byte
3
3
Arithmetic
Logic
REV. PrB
–11–
PRELIMINARY TECHNICAL DATA
ADuC842
XRL A,Rn
Exclusive-OR register to A
1
1
XRL A,@Ri
Exclusive-OR indirect memory to A
2
2
XRL A,#data
Exclusive-OR immediate to A
2
2
XRL dir,A
Exclusive-OR A to direct byte
2
2
XRL A,dir
Exclusive-OR indirect memory to A
2
2
XRL dir,#data
Exclusive-OR immediate data to direct
3
3
CLR A
Clear A
1
1
CPL A
Complement A
1
1
SWAP A
Swap Nibbles of A
1
1
RL A
Rotate A left
1
1
RLC A
Rotate A left through carry
1
1
RR A
Rotate A right
1
1
RRC A
Rotate A right through carry
1
1
MOV A,Rn
Move register to A
1
1
MOV A,@Ri
Move indirect memory to A
1
2
MOV Rn,A
Move A to register
1
1
MOV @Ri,A
Move A to indirect memory
1
2
MOV A,dir
Move direct byte to A
2
2
MOV A,#data
Move immediate to A
2
2
MOV Rn,#data
Move register to immediate
2
2
MOV dir,A
Move A to direct byte
2
2
MOV Rn, dir
Mov register to direct byte
2
2
MOV dir, Rn
Move direct to register
2
2
MOV @Ri,#data
Move immediate to indirect memory
2
2
MOV dir,dir
Move direct byte to direct byte
3
3
MOV dir,#data
Move immediate to direct byte
3
3
MOV DPTR,#data
Move immediate to data pointer
3
3
MOVC A,@A+DPTR
Move code byte relative DPTR to A
1
4
MOVC A,@A+PC
Move code byte relative PC to A
1
4
MOVX A,@Ri
Move external (A8) data to A
1
4
MOVX A,@DPTR
Move external (A16) data to A
1
4
MOVX @Ri,A
Move A to external data (A8)
1
4
MOVX @DPTR,A
Move A to external data (A16)
1
4
PUSH dir
Push direct byte onto stack
2
2
POP dir
Pop direct byte from stack
2
2
XCH A,Rn
Exchange A and register
1
1
XCH A,@Ri
Exchange A and indirect memory
1
2
XCHD A,@Ri
Exchange A and indirect memory nibble
1
2
XCH A,dir
Exchange A and direct byte
2
2
Data Transfer
Boolean
–12–
Rev.PrB
PRELIMINARY TECHNICAL DATA
ADuC842
CLR C
Clear carry
1
1
CLR bit
Clear direct bit
2
2
SETB C
Set Carry
1
1
SETB bit
Set direct bit
2
2
CPL C
Complement carry
1
1
CPL bit
Complement direct bit
2
2
ANL C,bit
AND direct bit and carry
2
2
ANL C,/bit
AND direct bit inverse to carry
2
2
ORL C,bit
OR direct bit and carry
2
2
ORL C,/bit
OR direct bit inverse to carry
2
2
MOV C,bit
Move direct bit to carry
2
2
MOV bit,C
Move carry to direct bit
2
2
JMP @A+DPTR
Jump indirect relative to DPTR
1
3
RET
Return from subroutine
1
4
RETI
Return from interrupt
1
4
ACALL addr11
Absolute jump to subroutine
2
3
AJMP addr11
Absolute jump unconditional
2
3
SJMP rel
Short jump (relative address)
2
3
JC rel
Jump on carry = 1
2
3
JNC rel
Jump on carry = 0
2
3
JZ rel
Jump on accumulator = 0
2
3
JNZ rel
Jump on accumulator != 0
2
3
DJNZ Rn,rel
Decrement register, jnz relative
2
3
LJMP
Long jump unconditional
3
4
LCALL addr16
Long jump to subroutine
3
4
JB bit,rel
Jump on direct bit = 1
3
4
JNB bit,rel
Jump on direct bit = 0
3
4
JBC bit,rel
Jump on direct bit = 1 and clear
3
4
CJNE A,dir,rel
Compare A, direct JNE relative
3
4
CJNE A,#data,rel
Compare A, immediate JNE relative
3
4
CJNE Rn,#data,rel
Compare register, immediate JNE relative
3
4
CJNE @Ri,#data,rel
Compare indirect, immediate JNE relative
3
4
DJNZ dir,rel
Decrement direct byte, JNZ relative
3
4
No operation
1
1
Branching
Miscellaneous
NOP
Notes:
1. One cycle is one clock.
2. Cycles of MOVX instructions are 4 cycles when they have 0 wait state. Cycles of MOVX instructions are 4+n cycles
when they have n wait states.
3. Cycles of LCALL instruction are 3 cycles when the LCALL instruction comes from interrupt.
REV. PrB
–13–
PRELIMINARY TECHNICAL DATA
ADuC842
I 2C-COMPATIBLE INTERFACE
The ADuC842 supports a fully licensed* I2C serial interface.
The I2C interface is implemented as a full hardware slave
and software master. SDATA is the data I/O pin and
SCLOCK is the serial clock. These two pins are shared with
the MOSI and SCLOCK pins of the on-chip SPI interface.
To enable the I2C interface the SPI interface must be turned
off (see SPE in SPICON previously) OR the SPI interface
must be moved to P3.3, P3.4 and P3.5 via the CFG841.1
bit. Application Note uC001 describes the operation of this
interface as implemented is available from the
MicroConverter Website at www.analog.com/
microconverter.
Three SFRs are used to control the I2C interface. These are described below:
I2C Control Register
E8H
00H
Yes
I2CCON:
SFR Address
Power-On Default Value
Bit Addressable
Table I2CCON SFR Bit Designations Master Mode
Bit
Name
7
MDO
6
MDE
5
MCO
4
MDI
3
I2CM
2
1
0
----------
Description
2
I C Software Master Data Output Bit (MASTER MODE ONLY).
This data bit is used to implement a master I2C transmitter interface in software. Data written
to this bit will be outputted on the SDATA pin if the data output enable (MDE) bit is set.
I2C Software Master Data Output Enable Bit (MASTER MODE ONLY).
Set by user to enable the SDATA pin as an output (Tx).
Cleared by the user to enable SDATA pin as an input (Rx).
I2C Software Master Clock Output Bit (MASTER MODE ONLY).
This data bit is used to implement a master I2C transmitter interface in software. Data
written to this bit will be outputted on the SCLOCK pin.
I2C Software Master Data Input Bit (MASTER MODE ONLY).
This data bit is used to implement a master I2C receiver interface in software. Data on the
SDATA pin is latched into this bit on SCLOCK if the Data Output Enable (MDE) bit is ‘0.’
I2C Master/Slave Mode Bit.
Set by user to enable I2C software master mode.
Cleared by user to enable I2C hardware slave mode.
RSVD
RSVD
RSVD
Table I2CCON SFR Bit Designations Slave Mode
Bit
Name
7
I2CSI
6
I2CGC
5
4
I2CID1
I2CID0
3
I2CM
2
I2CRS
1
I2CTX
Description
2
I C Stop Interrupt Enable Bit.
Set by the user to enable I2C stop interrupts. If set a stop bit that follows a valid start
condition will generate an interrupt.
Cleared by the user to disable I2C stop interrupts.
I2C General Call Status Bit
Set by hardware after receiving a general call address.
Cleared by the user.
I2C Interrupt Decode Bits.
Set by hardware to indicate the source of an I2C interrupt
00 Start and Matching Address
01 Repeated Start and Matching Address
10 User Data
11 Stop after a Start and Matching Address
I2C Master/Slave Mode Bit.
Set by user to enable I2C software master mode.
Cleared by user to enable I2C hardware slave mode.
I2C Reset Bit (SLAVE MODE ONLY).
Set by user to reset the I2C interface.
Cleared by user code for normal I2C operation.
I2C Direction Transfer Bit (SLAVE MODE ONLY).
Set by the MicroConverter if the interface is transmitting.
–14–
Rev.PrB
PRELIMINARY TECHNICAL DATA
ADuC842
0
I2CI
Cleared by the MicroConverter if the interface is receiving.
I 2C Interrupt Bit (SLAVE MODE ONLY).
Set by the MicroConverter after a byte has been transmitted or received.
Cleared automatically when user code reads the I2CDAT SFR (see I2CDAT below).
I2CADD
Function
I2C Address Register
Holds the first I2C peripheral address for the part. It may be overwritten by user code.
Technical NoteuC001 at www.analog.com/microconverter describes the format of the
I2C standard 7-bit address in detail.
SFR Address
Power-On Default Value
Bit Addressable
9BH
55H
No
I2CADD1
Function
I2C Address Register
Holds the second I2C peripheral address for the part. It may be overwritten by user code.
SFR Address
Power-On Default Value
Bit Addressable
91H
00H
No
I2CADD2
Function
I2C Address Register
Holds the third I2C peripheral address for the part. It may be overwritten by user code.
SFR Address
Power-On Default Value
Bit Addressable
92H
00H
No
I2CADD3
Function
I2C Address Register
Holds the fourth I2C peripheral address for the part. It may be overwritten by user code.
SFR Address
Power-On Default Value
Bit Addressable
93H
00H
No
I2CDAT
I2C Data Register
The I2CDAT SFR is written by the user to transmit data over the I2C interface or read by
user code to read data just received by the I2C interface. Accessing I2CDAT automatically clears
any pending I2C interrupt and the I2CI bit in the I2CCON SFR. User software should only
access I2CDAT once perinterrupt cycle.
SFR Address
9AH
Power-On Default Value 00H
Bit Addressable
No
Function
* Purchase of licensed I 2 C components of Analog Devices or one of its sublicensed Associated Companies conveys a license for the purchaser
under the Philips I 2 C
Patent Rights to use the ADuC842 in an I 2C system, provided that the system conforms to the I 2 C Standard Specification as defined by
Philips.
REV. PrB
–15–
PRELIMINARY TECHNICAL DATA
ADuC842
acknowledge bits, data bytes and STOP conditions appropriately. These functions are provided in tech note uC001.
The main features of the MicroConverter I2C interface are:
- Only two bus lines are required; a serial data line
(SDATA) and a serial clock line (SCLOCK).
- An I 2 C master can communicate with multiple slave
devices. Because each slave device has a unique 7-bit
address then single master/slave relationships can exist
at all times even in a multi slave environment
- Ability to respond to 4 seperate addresses when operating in slave mode
- An I 2 C slave can respond to repeated start conditions
without a stop bit in between. This allows a master to
change direction of transfer without giving up the bus.
- On-Chip filtering rejects <50ns spikes on the SDATA
and the SCLOCK lines to preserve data integrity.
Hardware Slave Mode
After reset the ADuC842 defaults to hardware slave mode.
The I2C interface is enabled by clearing the SPE bit in
SPICON. Slave mode is enabled by clearing the I2CM bit
in I2CCON. The ADuC842 has a full hardware slave. In
slave mode the I2C address is stored in the I2CADD register. Data received or to be transmitted is stored in the
I2CDAT register.
Once enabled in I2C slave mode the slave controller waits for
a START condition. If the ADuC842 detects a valid start
condition, followed by a valid address, followed by the R/W
bit the I2CI interrupt bit will get automatically set by hardware.
The I2C peripheral will only generate a core interrupt if the
user has pre-configured the I2C interrupt enable bit in the
IEIP2 SFR as well as the global interrupt bit EA in the IE
SFR. i.e.
DV DD
I2 C
MA STER
; Enabling I2C
MOV
IEIP2,#01h
SETB EA
I2 C
SLAVE#1
On the ADuC841 an auto-clear of the I2CI bit is implemented so this bit is cleared automatically on a read or write
access to the I2CDAT SFR.
MOV
MOV
I2 C
SLAVE#2
I2CDAT, A
A, I2CDAT
; I2CI auto-cleared
; I2CI auto-cleared
If for any reason the user tries to clear the interrupt more
than once i.e. access the data SFR more than once per interrupt then the I2C controller will halt. The interface will then
have to be reset using the I2CRS bit.
Figure 36. Typical I2C System
Software Master Mode
The ADuC841 can be used as a I2C master device by configuring the I2C peripheral in master mode and writing sotware
to output the data bit by bit. This is referred to as a software
master. Master mode is enabled by setting the I2CM bit in
the I2CCON register.
To transmit data on the SDATA line, MDE must be set to
enable the output driver on the SDATA pin. If MDE is set
then the SDATA pin will be pulled high or low depending
on whether the MDO bit is set or cleared. MCO controls the
SCLOCK pin and is always configured as an output in master mode. In master mode the SCLOCK pin will be pulled
high or low depending on the whether MCO is set or
cleared.
To receive data, MDE must be cleared to disable the output
driver on SDATA. Software must provide the clocks by toggling the MCO bit and read SDATA pin via the MDI bit. If
MDE is cleared MDI can be used to read the SDATA pin.
The value of the SDATA pin is latched into MDI on a rising
edge pf SCLOCK. MDI is set if the SDATA pin was high
on the last rising edge of SCLOCK. MDI is clear if the
SDATA pin was low on the last rising edge of SCLOCK.
Software must control MDO, MCO and MDE appropriately to generate the START condition, slave address,
Interrupts for the ADuC831
; enable I2C interrupt
The user can choose to poll the I2CI bit or enable the interrupt. In the case of the interrupt the PC counter will vector
to 003BH at the end of each complete byte. For the first byte
when the user gets to the I2CI ISR the 7-bit address and the
R/W bit will appear in the I2CDAT SFR.
The I2CTX bit contains the R/W bit sent from the master.
If I2CTX is set then the master would like to receive a byte.
Hence the slave will transmit data by writing to the I2CDAT
register. If I2CTX is cleared the master would like to transmit a byte. Hence the slave will receive a serial byte.
Software can interrogate the state of I2CTX to determine
whether is should write to or read from I2CDAT.
Once the ADuC842 has received a valid address, hardware
will hold SCLOCK low until the I2CI bit is cleared by software. This allows the master to wait for the slave to be ready
before transmitting the clocks for the next byte.
The I2CI interrupt bit will be set every time a complete data
byte is received or transmitted provided it is followed by a
valid ACK. If the byte is followed by a NACK an interrupt is
NOT generated. The ADuC842 will continue to issue interrupts for each complete data byte transferred until a STOP
condition is received or the interface is reset.
When a STOP condition is received, the interface will reset
to a state where it is waiting to be addressed (idle). Similarly, if the interface receives a NACK at the end of a
sequence it also returns to the default idle state. The I2CRS
bit can be used to reset the I2C interface. This bit can be
used to force the interface back to the default idle state.
–16–
Rev.PrB
PRELIMINARY TECHNICAL DATA
ADuC842
OUTLINE
DIMENSIONS
Dimensions shown in inches and (mm).
52-Lead Plastic Quad Flatpack
(S-52)
64
3, 1 6($7,1*
3/$1(
723 9,(:
3,16 '2:1
64
%6&
56Lead Chip Scale Package(CP-56)
BSC SQ
3,1 ,1',&$725
%6& 64
723
9,(:
0,1
43
42
56
1
%27720
9,(:
29
28
64
14
15
5()
0$;
R
0$;
120
0$;
120
%6&
REV. PrB
–17–
5()
This datasheet has been download from:
www.datasheetcatalog.com
Datasheets for electronics components.