Analog Devices MICROCONVERTER ADUC812 User manual

ADUC812 EVALUATION BOARD
REFERENCE GUIDE
MICROCONVERTERADUC812
QUICKSTARTDEVELOPMENT SYSTEM

ADuC812 Evaluation Board Reference Guide
Evaluation Board Overview
CONTENTS:
Evaluation Board Reference Guide:
1) Evaluation Board Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2) Evaluation Board Features . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
3) Link options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
4) External Junctions (Connectors) . . . . . . . . . . . . . . . . . . . . . . . 9
5) LDR Demonstration Circuit . . . . . . . . . . . . . . . 11
6) Parts List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
(1) EVALUATION BOARD OVERVIEW
The ADuC816 Evaluation board has the following features :
• 2 Layer PCB (4” X 5” Form Factor)
• 9V power supply/battery regulated to 5V on board (see section 2)
• 4 Pin Header Interface to RS232 dongle cable
• Access to all ADC inputs from external header. DAC output channel buffered to external header.
(see section 2 and section 4)
• All device Ports and Strobes are brought out to external header pins (see section 4)
• General Purpose Prototype Area (see section 2)
• 32KBytes External memory (SRAM) (configurable as data or volatile program memory) (see
section 2 and section 3)
• External Program Memory Socket for NV program memory (see section 2)
• 11.0592MHz Crystal (see section 2)
• Reset/External Interrupt 0 Push Buttons (see section 2)

ADuC812 Evaluation Board Reference Guide
Evaluation Board Overview
• Power Indicator/General Purpose LEDs (see section 2)
• Example LDR Demonstration Circuit (see section 5)
NOTES :
1. All references in this document to physical orientation of components on the board are made with respect to a component
side view of the board with the battery connections appearing in the top right corner of the board.
2. The board is laid out to minimize coupling between the analog and digital sections of the board. To this end, the ground
plane is split with the analog section on the right hand side and a digital plane on the left hand side of the board. The
regulated 5V power supply is routed directly to the digital section and is filtered before being routed into the analog section
of the board.
3. The ADuC812 can be socketed on the board using a QFP carrier adaptor and corresponding surface mount feet available
from Ironwood Electronics The part numbers are CA-QFE52SB-L-Z-T-01 and SF-QFE52SB-L-01 respectively.
WEB: www.ironwoodelectronics.com
Email: [e-mail]

ADuC812 Evaluation Board Reference Guide
Evaluation Board Features
(2) EVALUATION BOARD FEATURES
Power Supply:
A 9V supply is fed to the board via the 2.1mm input power socket (J4). The input connector is configured
as ‘CENTER NEGATIVE’i.e. GND on the center pin and +9V on the outer shield. Alternatively the user
can connect a 9V battery via J9(-) and J10(+). The 9V supply is regulated via a linear voltage regulator
(U9), the 5V output being used to drive the digital side of the board directly. The 5V supply is also
filtered and then used to supply the analog side of the board.
When on, the green LED (D2) indicates that a valid 5V supply is being driven from the regulator circuit.
All analog supplies are decoupled with 10uF and 0.1uF at device supply pins. Digital supplies are
decoupled with 0.1uF at the digital supply pins.
RS232 Interface:
The ADuC812 (U1) TXD and RXD (pins 17 and 16 respectively) lines are connected to a header. The
cable which is included as part of the QuickStart Development System has a RS232 transciever at the
connecting end. This cable can be used to connect to both the evaluation board and the adaptor board.
Analog I/O Connections:
The inputs to the primary ADC are filtered with a first order (RC) anti-aliasing filter.
General Purpose prototype area
General Purpose prototype areas are provided at the top and the bottom or the evaluation board for adding
external components as required in the users application. As can be seen from the layout AVDD, AGND,
DVDD and DGND tracks are provided in this prototype area.
External Data Memory Interface:
The Evaluation board incorporates 32KBytes SRAM (U7). This external memory can be configured as a
data memory or as both code and data memory. Typically the 32Kbytes will be used as external data
memory. To configure it as switch link4 to the off position.
The MicroConverter uses a 24-bit address interface to external memory unlike a standard 8051, which
only uses 16-bit addresses. This means that the MicroConverter can address up to 16MBytes of XRAM
while the 8051 can only address 64kBytes of XRAM. This is done by multiplexing Port2 (high address
byte + page address byte) as well as Port0 (low address byte + data byte).
The ADuC812 evaluation board only contains 32kBytes of XRAM. Hence the full 24-bit address interface
to the XRAM cannot be used properly. To show this feature off we have configured the memory in two
modes using LK12 as discussed in section 1.2. The memory is addressed using 2 external latches
(74HC573, U14 and U15). U14 is used to latch the low order address on Port 0 before it multiplexes to a
data bus. U15 is used to multiplex Port2.
Note: U14 is unnecessary if the ADuC812 is addressing less than 64kBytes of XRAM.

ADuC812 Evaluation Board Reference Guide
Evaluation Board Features
Configuring the memory as a code memory might be useful in some applications. It is necessary for the
Keil Monitor-51 which requires von-Neumann wired code and XData memory. To configure this memory
as a data and code memory switch link 4 to the on position.
Note: If using the external data memory as both external program memory and external data
memory make sure that there is no external program memory in the program memory socket
provided, (U12). Switching on LK4 with a an external program memory inserted in U12 will cause
both U7 and U12 to be enabled together and will cause confliction on the data bus.
External Program Memory Socket:
An external program memory socket is available on the ADuC812 evaluation board. This allows the user
to easily connect in an external program memory.
Note: If using an external program meory at U12 make sure that LK4 is switched to the off position
as described above.
Crystal Circuit:
The board is fitted with a 11.0592MHz crystal. This crystal is connected between the XTAL1 and XTAL2
pins. 2 X 33pF surface mount caps are used to connect XTAL1 and XTAL2 to ground.
External Power on Reset Chip (ADM809)
An external power on reset chip is used to drive the RESET pin on the ADuC812. Because we want a
push button switch available to the user an active low Power on Reset chip (ADM809) is used with
5(6(7 output inverted (using a PNP BJT) before being connected to the RESET pin of the
MicroConverter.
DVDD
RESET
48
34
20 ADuC812
15
OPTIONAL
MANUALRESET
PUSH-BUTTON
POR
(ACTIVE LOW)
POWER SUPPLY
1k⍀
Alternatively, if a push button switch is not required, the RESET output of an active high power
on reset chip (e.g. ADM810) can be used to directly drive the RESET pin of the ADuC812.
DVDD
RESET
48
34
20
15
ADuC812
POR
(ACTIVE HIGH)
POWER SUPPLY
Reset/,17 Push Buttons:

ADuC812 Evaluation Board Reference Guide
Evaluation Board Features
A RESET push button is provided to allow the user to manually reset the part. This button is at the input
to the ADM809 (Power on Reset chip) so a delay of 240ms approx will be required for the part to be
actually released from reset after the button is released.
An ,17 push button switch is provided to allow the user perform external interrupts easily. The ,17
signal is Schmitt triggered (U5) to prevent noise on the rising edge of ,17 to cause multiple interrupts
as it passes the trip point. This Schmitt trigger also inverts the signal.
Power Indicator/General Purpose LEDs:
A green power LED (D2) is used to indicate that a sufficient supply is available on the board. A red
general purpose LED (D1) is connected to P3.4 of the ADuC812. An inverter is connected between the
LED and the port pin so that the SETB instruction turns the LED on and the CLR instruction turns the
LED off.

ADuC812 Evaluation Board Reference Guide
(3) LINK OPTIONS
LK1 (2x1) LDR Demo Connection
Function: Allows the user to connect the output of the voltage divider to ADC1.
Use : Slide LK1 into the ON position to connect the output of the voltage divider to ADC1.
Slide LK1 into the OFF position for normal operation of analog input ADC1.
LK2 (2x1) DAC0 Buffer LED Link
Function : Allows the DAC0 buffer to be connected to LED. This forms part of the LDR application
circuit.
Use : Insert LK2 to connect the DAC0 buffer to the LED
Remove LK2 to disconnect the DAC0 buffer from the LED.
LK3 (2x1) 36(1Pulldown for Serial Download/Debug Mode
Function: Allows the user to enter serial download or debug mode.
Use : Slide LK3 into the ON position to enter serial download mode or debug mode on power-on or
after a hardware reset (i.e. pressing reset button).
Slide LK3 into the OFF position for normal device operation.
LK4 (2x1) Connect PSEN to External Data Memory
Function : Allows the External Data Memory to be used as both an External Program Memory and an
External Data Memory.
Use : Slide LK4 into the ON position to connect the PSEN output from the ADuC812 (for use
with an external program memory) through an AND gate to the external data memory. This
allows the external Data Memory to be used as both external program and data memory.
Note: To use this mode make remove any external program memory inserted in the external
program memory socket provided (U12) as this will cause confliction on the data bus.
Slide LK4 into the OFF position to disconnect the 36(1 signal from the data memory,
disabling the use of the external data memory as an external program memory.
LK5,6,7 These 2-way links are used to route multi-function pins on Port 1 from the analog side of the
board to the digital side of the board as detailed below. With these links removed the digital
function is isolated from the digital side of the board, thus minimizing any feedthrough
/coupling onto the analog side of the board.
LK5 (2x1) Connect 66to SPI/I2C Connector
Function: Allows the 66 pin to be connected to the SPI/I2C connector

ADuC812 Evaluation Board Reference Guide
Use : Slide LK5 into the ON position to connect the 66 pin to the external SPI/I2C connector.
Slide LK3 into the OFF position for normal device operation of analog input ADC5.
LK6 (2x1) Connect T2to Time/Strobe Connector
Function: Allows the T2 pin to be connected to the Timer/Strobe connector
Use : Slide LK6 into the ON position to connect the T2 pin to the external Timer/Strobe connector.
Slide LK6 into the OFF position for normal device operation of analog input ADC0.
LK7 (2x1) Connect T2EXto Time/Strobe Connector
Function: Allows the T2EX pin to be connected to the Timer/Strobe connector
Use : Slide LK7 into the ON position to connect the T2EX pin to the external Timer/Strobe
connector.
Slide LK7 into the OFF position for normal device operation of analog input ADC1.
LK8 (2x1) Connect Waveform Generator Circuit
Function: This 3-way link is used to route a specific waveform (sine, square, triangular) onto ADC
channel 0 as detailed below.
The frequency of the generated waveform is 723Hz in each case.
Use: Insert Link in Position A to conntect triangular wave to ADC0
Insert Link in Position B to conntect square wave to ADC0
Insert Link in Position C to conntect sine wave to ADC0
LK9,10 (2x1) I2C Pullup Resistor Connections
Function: This connects the 1KΩpullup resistors that are required for I2C operation.
Use : Slide LK9,10 into the ON position to connect the I2C pullup resistors.
Slide LK9,10 into the OFF position for normal device operation.
LK11 (2x1) ($ Pulldown
Function: Allows the user to force the ADuC812 to execute the first 8kBytes of program memory from
the internal or external program memory space.
Use : Insert LK11 to pull ($ low causing the ADuC812 to run code from external program
memory.
Remove LK11 to leave ($ high so as to run code from the internal Flash/EE program
memory.

ADuC812 Evaluation Board Reference Guide
Note: This link can also be used with the Accutron ACE emulator. The single pin emulator
simply connects to this link.
LK12 (3x1) External Data Memory
Function: This link is used to configure the external data memory map. Either the bottom 32k Bytes of
the external data memory space is mapped or the bottom 256 bytes in the first 128 pages is
mapped. (via A16-A23 and U4).
Use : Slide LK12 to Position A to make U14 transparent. Hence the external data memory (U7) sees
address lines A0-A14. Hence the bottom 32K Bytes of the address range are mapped into the
external data memory space.
Note: In this mode (using less than 64k Bytes of XRAM) the latch U14 is unnecessary.
Slide LK9 to Position B to allow ALE to latch U14. Hence the external data memory (U7)
sees the address lines A0-A7 and A16-A22. Hence the bottom 256 Bytes in the first 128 pages
of the address range are mapped into the external data memory space.
Note: This mode may not be of particular use to the user but it does show the 24 bit
addressing ability of the MicroConverter.

ADuC812 Evaluation Board Reference Guide
(4) EXTERNAL JUNCTIONS(CONNECTORS):
J1 Analog I/O Connector
The analog I/O connector J1 carries all ADC inputs and DAC output channels as well as the external VREF
input. The pinout and orientation of this connector is shown below.
8
1
2
3
4
5
6
79
10 16
11
12
13
14
15 17
18
19
20
21
22
Figure 2: The Analog I/O connector J2
Pin Function Pin Function
1 ADC0 12 AGND
2 AGND 13 ADC6
3 ADC1 14 AGND
4 AGND 15 ADC7
5 ADC2 16 AGND
6 IN(+) OP-AMP (spare) 17 DAC0
7 ADC3 18 Out OP-AMP
8 IN(-) OP-AMP (spare) 19 DAC1
9 ADC4 20 AGND
10 DAC ADJUST 21 VREF
11 ADC5 22 AGND
Table 1: Pin functions for Analog I/O connector J2
J2 Serial Interface Connector
J2 provides a simple connection of the evaluation board to the PC via a dongle cable (provided with the
ADuC812 QuickStart Development System).
J3/J6/J7 (Port0 / Port2 / Port 3)
3 parallel ports (Port0, Port2 and Port3) are brought out to the connectors J4, J5 and J6. The exact pinout
of any of these connectors is shown below with reference to figure 3.
Figure 3: 10 way Connector Port
8
1
2
3
4
5
6
79
10

ADuC812 Evaluation Board Reference Guide
Pin Function Pin Function
1 PortX.0 6 PortX.5
2 PortX.1 7 PortX.6
3 PortX.2 8 PortX.7
4 PortX.3 9 DGND
5 PortX.4 10 DGND
Table 2: Pin functions for Port0, Port2 and Port3 connectors J3, J6, J7
J4/J9/J10 Power Supply Connections
J4 allows for the connection between the evaluation board and the 9V power supply provided in the
ADuC812 QuickStart Development System.
J9 and J10 allow for the connection of a typical 9V battery to the evaluation board.
J5 (SPI/I2C Connector)
J5 is situated to the left side of the board and gives access to both the SPI and I2C interfaces. The pinout is
as in fig 3 with the orientation vertical. Look for the pin1 marker on the evaluation board.
Pin Function Pin Function
1 SCLOCK 6 DGND
2 DGND 7 66
3 SDATA/MOSI 8 DGND
4 DGND 9 NC
5 MISO 10 DGND
Table 3: Pin functions for SPI connector J7
J8 (Timer/Strobe)
The timer/strobe control signals on the ADuC812 are all brought out to a 10 way connection port just
above the prototyping. The exact pinouts of the ports are shown in table 2 with reference to the connector
shown in figure 3.
Pin Function Pin Function
1 T0 6 T2
2 T1 7 T2EX
3 ($ 8 DGND
4 36(1 9 DGND
5 ALE 10 DGND
Table 4: Timer/Strobe connector J3

ADuC812 Evaluation Board Reference Guide
(5) LDR DEMONSTRATION CIRCUIT
USING THE LDR CIRCUIT:
As can be seen from examining the schematic an example LDR circuit is connected shown in Figure 2
below:
ADC DAC
VDD
VDD
Application
Code
LK1
LK2
Circuit diagram of the LDR Circuit
Using the sample code in \code\adc\adcldr.asm the variation in the resistance of the ldr can be seen by the
reducing brightness of the output led as the amount of light is decreased.

ADuC812 Evaluation Board Reference Guide
ADuC812 Evaluation Board Parts List
Version 1.0 Analog Devices Inc., MicroConverter
www.analog.com/microconverter
(6) ADUC812 EVALUATION BOARD PARTS LIST
Component Qty Part Description Order No Order From
EVAL- ADuC812QS QuickStart PCB 1 PCB-1 2 sided surface mount PCB
PCB Stand-off 4 Stand-off Stick on mounting feet 148-922 Farnell
U1 1 ADuC812 MicroConverter (52PQFP) ADI
U2,U3 2 OP491G Quad OP-Amp, 14 pin SOIC ADI
U4,U10 2 OP284ES Dual Op-Amp, 8 pin SOIC ADI
U5 1 MM74HC14M Hex Schmitt-Trigger Inv, 14 pin SOIC 379-268 Farnell
U6 1 NC7S08M5 Single And Gate 685-925 Farnell
U7 1 HY62256B LLT1-70 32Kx8 CMOS SRAM, 28Pin TSOP 352-8509 Farnell
U8 1 ADM908RART Power on Reset Supervisory Chip ADI
U9 1 MC7805CT Fixed 5V Linear Voltage Regulator 701-853 Farnell
U11 1 AD820AR Single OP-Amp, 8 pin SOIC ADI
U13 1 NE555D Timer, 8 pin SOIC 409-352 Farnell
U14,U15 2 MM74HC573WM Octal D-Type Transparent Latch, SOIC 379-580 Farnell
SW1,SW2 2 Push Button Switch PCB Mounted Push Button Switch 176-432 Farnell
D1 1 Red Led 1.8mm miniture red led 657-025 Farnell
D2 1 Green Led 1.8mm miniture green led 657-037 Farnell
D3,D4 2 1N4001 Diode 365-117 Farnell
D5 1 Yellow Led 1.8mm miniture red led 657-049 Farnell
Q1 1 BC856 PNP General Purpose Transistor 506-266 Farnell
L1,L2 2 Ferrite Bead Surface Mount Inductor, 1206 Case 557-330 Farnell
LK1-7,LK9-10, 9 SPST Switch Header 2x1 SPST Switch Header 986-501 Farnell
LK12 1 SP Changeover Header SP3T Changeover Header JsC4-16-GO Futora Electronics
LK11 1 2x1(with Friction Lock) Square Pin Header with friction lock 143-139 Farnell
R1-R8 8 51R Surface Mount Resistor, 0805 Case 771-181 Farnell

ADuC812 Evaluation Board Reference Guide
ADuC812 Evaluation Board Parts List
Version 1.0 Analog Devices Inc., MicroConverter
www.analog.com/microconverter
R14,R21-R27,R9,R30,R33, 11 1K Surface Mount Resistor, 0805 Case 613-095 Farnell
R10,R34 2 100K Surface Mount Resistor, 0805 Case 613-332 Farnell
R11, R12,R29 3 270R Surface Mount Resistor, 0805 Case 613-022 Farnell
R13 1 1R5 Surface Mount Resistor, 0805 Case 758-310 Farnell
R15,R19 2 22K Thick Film Networks 770-63-R22K-ND Digikey Catalog
R16 1 15K Surface Mount Resistor, 0805 Case 613-230 Farnell
R17 1 3K9 Surface Mount Resistor, 0805 Case 613-162 Farnell
R18 1 330R Surface Mount Resistor, 0805 Case 613-034 Farnell
R20 1 8K2 Surface Mount Resistor, 0805 Case 613-204 Farnell
R28 1 2K2 Surface Mount Resistor, 0805 Case 613-137 Farnell
R32 1 LDR MPY54C569 Light Dependant Resistor 179-611 Farnell
R31 1 20K Surface Mount Resistor, 0805 Case 771-491 Farnell
R35 1 0R Surface Mount Resistor, 0805 Case 772-239 Farnell
C1-C8,C10,C18,C17,C16 12 0.01uF SM Cap Surface Mount Ceramic Cap, 0805 Case 499-225 Farnell
C11 1 0.33uF SM Cap Surface Mount Tantalum Cap, Taj-A Case 498-919 Farnell
C15,C24-C26,C28,C36 6 10uF SM Cap Surface Mount Tantalum Cap, Taj-A Case 197-130 Farnell
C12,C13, 2 10uF SM Cap Surface Mount Tantalum Cap, Taj-B Case 498-737 Farnell
C9,C14,C21-23,C27,C29,C31-35 12 0.1uF Surface Mount Ceramic Cap, 0603 Case 499-675 Farnell
C20,C30 2 33pF Surface Mount Ceramic Cap, 0603 Case 498-555 Farnell
C19 1 0.1uF Surface Mount Ceramic Cap, 0805 Case 499-687 Farnell
J1 1 11X2 Pin Header Double Row Link Header .148-535 Farnell
J2 1 4x1 Pin Header Single Row Link Header 511-729 Farnell
J3,J5,J6,J7,J8 5 5X2 Pin Header Double Row Link Header 511-808 Farnell
J4 1 PCB Mounted Socket PCB Mounted Socket (2.1mm Pin Diameter) .224-959 Farnell
J9 1 9V Snap On Battery connector Male 723-988 Farnell
J10 1 9V Snap On Battery connector Female 723-988 Farnell
LK8 1 3X2 Pin Header Double row link header .148-535 Farnell
T1 1 Testpoint Raised Loop Testpoint 240-345 Farnell
1 11.0592MHz Crystal Watch Crystal in HC49/4H 263-734 Farnell Catalog Pg. 1426