Nova N13072 User manual

N13072
ADS168
12-Bit Analog Industrial Interface Board
Nova Research and Engineering, Inc.
11930A 44
th Street North
Clearwater, FL 33762
[phone]
6/17/2010

ADS168 Analog Industrial Interface Board
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Products manufactured by Nova Research and Engineering, Inc. (NRE), Clear water,
Florida are warranted against defects in materials and workmanship for a period of one
year from the original date of delivery. Factory reconditioned and refurbished products
are warranted against defects in materials and workmanship for a period of 90 days from
the date of delivery.
This warranty does not cover damage from, or failure attributable to, acts of nature,
abuse, misuse, improper usage, faulty installation, or any modifications not expressly
authorized in writing by NRE.
NRE will repair or replace, at our option, any product determined to be defective within
the terms of this warranty. After the warranty period, charges will be rendered for any
repairs, adjustments or upgrades made to the product by NRE, including, but not limited
to, charges for shipping, insurance, parts and labor.
NRE is not responsible or liable for indirect, special, or consequential damages arising
out of, or in connection with, the use or performance of any NRE products. NRE is not
responsible or liable for other damages with respect to loss of property, loss of revenues
or profit, or costs of removal, installation or reinstallation.
Except as provided herein, NRE makes no express warranties, and any implied
warranty, including warranties of merchantability or fitness for a particular purpose, is
limited to a period of ninety days from the original date of delivery.
This warranty gives you specific legal rights. You may have additional rights that vary
from state to state.
Rev A (printed Jan 1999)
Rev B (printed Ju ne 2009)
Rev C (printed June 2010)
Robotrol and ADA88 are trademarks of Robotrol Corporation.
IBM is a registered trademark of International Business Machines.
Windows and Windows 3.1 are trademarks of Microsoft Corporation.
No part of this publication may be reproduced, stored in a retrieval system, or
transmitted, in any form or by any means without prior written permission of Nova
Research and Engineering, Inc.
The information contained herein is subject to change without notice.
Copyright (c) 1999 - 2010 by Nova R esearch and Engineering, Inc. (USA).
All rights reserved.

ADS168 Analog Industrial Interface Board
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Table of Contents
1 Introduction............................................................................................... 4
2 Installation.................................................. ............................................... 5
2.1 Card Configuration.................................................................................... 5
3 Operation.................................................................................... .............. 7
Board Initialization ................. .............................................. 9
Input Programming ...................................... ......... 9
Analog Output Programming .. .. ............ ..... .... 11
4 Calibra tion......................... . ....................................................................... 14
4 .1 Output Calibration .................. .............................................. 14
5 Troubleshooting.................. . ..... ................................................................. 15
Appendix A Card Specifications....................................................................... 16
Appendix B Ordering and Service Information ..................................... ......... 18
Appendix C Programming Examples . ..... ............................................... 19
Appendix D Interface Connections . ..... ............................................... 24

ADS168 Analog Industrial Interface Board
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SECTION 1
Introduction
The ADS168 is a multifunction analog and digital I/O expansion board for ISA compatible
computers. The ADS168 board installs internally in a full-length expansion socket in an active or
passive backplane, and is addressed through the computer s I/O address space (no memory-
mapped addressing is supported). All analog and digital I/O is provided through a single 37- pin,
D- sub style female connector. The command protocol is backwardly compatible with the Robotrol
ADA88 analog expansion card. The ADS168 has been designed to provide years of reliable
performance in the most demanding, real - world control applications.
ADS168 Features. The ADS168 features sixteen analog inputs, eight analog outputs and 8 bits
of digital I/O. The board has a software selectable full-scale analog output voltage range of 5 or
10 VDC, software programmable variable gain input amplifier, ISA bus compatibility, and a high-
speed FIFO bus interface.
Analog Inputs. The sixteen analog inputs are single-ended (non-differential) and are converted
by a 12-bit analog- to -digital converter (ADC) circuit. The input amplifier has a software
programmable gain stage allowing gain settings of x1 (10VFS), x2 (5VFS), x4 (2.5 VFS ), or x8
(1.25VFS) . The A/D converter can perform one conversion per command or can continuously
scan the analog inputs. The analog inpu ts can be digitally filtered via an on - board microprocessor
(factory installed option).
Analog Outputs. There are eight 12-bit unipolar analog outputs capable of up to +10 VDC
range. Each output has a software selectable range of 5 or 10 VDC full-scale. Each output is
capable of sinking or sourcing 5 mA. Two analog outputs can be configured for up to 80 mA of
drive current (factory installed option).
Digital I/O. The eight-bit, bi-directional digital I/O port is TTL compatible. With a high- voltage
digi tal interface option, four bits are configured as 24 VDC open-collector output drivers and four
bits are configured as optically isolated inputs, requiring an active low signal.
ISA Bus Interface. The ISA bus interface uses high-speed CMOS logic which allows the host
system external I/O bus to run at maximum speed without the need for I/O expansion bus wait
states.

ADS168 Analog Industrial Interface Board
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SECTION 2
Installation
The ADS168 can be installed any 16 bit slot of an ISA compatible computer system, with an
active or passive backplane. When installing or removing the board, always use ESD handling
precautions.
The card is secured using a single screw to the computer rear card frame, as shown in Figure 1,
below. Any mix of cards may be plugged in, so long as the card addresses do not overlap. The
card address must be set before installation, and this process is described in Section 2.2, below.
The electrical and environmental specifications are shown in Section 5.
Figure 1 Cards secured in cardrack
2.1 Card Configuration
The board uses four of the addresses in one segment of the configured base address. Thus if the
base address is set to 320H, the board uses addresses 320H through 323 H. Utilization of the
address is shown in Table 2.1.
I/O Address Register
Data
Direction Function
addr + 0 INP DATA Write 8 bit data transfer register
addr + 0 OUT DATA Read 8 bit data transfer register
addr + 1 COMMAND Write Command register
addr + 1 STATUS Read Status register
addr +2 or addr +3 FIFO Read 256 byte output data FIFO
Table 2.1 - I/O address map
The base address of the board is set using jumpers W3 (bottom, right of board), and they
configure the bits 2 through 9 of the address in the computer I/O space. Normal configuration is
3XXH or 2XXH .
All of the analog and digital I/O functions of the ADS168 are software configurable and do not
require additional jumper settings. The base address and interrupt (IRQ) settings are the only
options that require jumper configuration.
Base I/O Address. The board base I/O address is set by jumper block W3 ( Table 2.1). The
board uses four sequential I/O locations and can be placed at any I/O base address from 000H to
3FCH, in four-byte increments. The factory setting for the base address is 0300H. Typical
settings are shown below:

ADS168 Analog Industrial Interface Board
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300H
304H
308H
30CH
310H
.
.
A2
X X X
.
.
A3
X
X
X
.
.
A4
X
X
X
X
. .
A5
X
X
X
X
X
. .
A6
X
X
X
X
X
. .
A7
X
X
X
X
X
.
.
A8
.
.
A9
W3
X = Jumper installed
Table 2.1 - W3 Base I/O Address Settings
Several address settings are shown in the following photographs (Figure 2). The progression is
binary.
Address=0x300 Address=0x30 4 Address=0x30 8
Address=0x30C Address=0x3 10
Figure 2 Some address settings
Interrupts. The ADS168 can be configured to generate a host CPU interrupt (IRQ) when the
output buffer full (OBF) bit is set in the status register. The board can generate an interrupt on
IRQ 3, 4, 5, 6, 7, 10, 11, 12, 14, or 15 (see Table 2.2). By installing a jumper on W1 or W2, an
interrupt will be generated once the board is initialized and an A/D request has been processed.
To disable the interrupt feature, remove the IRQ jumper from W1 or W2. The factory default
setting is NO IRQ (no jumpers installed) .

ADS168 Analog Industrial Interface Board
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.
.
IRQ14
.
.
IRQ7
.
.
IRQ15
.
.
IRQ6
.
.
IRQ12
.
.
IRQ5
.
.
IRQ11
.
.
IRQ4
.
.
IRQ10
.
.
IRQ3
W1 W2
Table 2.2 - W1, W2 IRQ Jumper Settings
Use only one IRQ setting for each board in the host system. Refer to Chapter 6 for more
information on host system IRQ settings and problem sol ving. A photograph of the card showing
W1 and W2 is shown below (Figure 3) .
Figure 3 W1 and W2 Connectors
Input and Output Connections. All analog and digital I/O is performed through the J1
connector. The J1 connector is a 37 pin D- sub miniature, jack (female) style connector. An
additional 38 pin header connector can be provided at J2 for analog and digital ground
connections (factory option). Refer to Appendix D for more information on interface signals and
locations.

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SECTION 3
O peration
This section describes the command, status and data formats for programming the ADS168. All
data is transferred in 8 - bit I/O bus transfers to and from registers on the ADS168.
I/O Address Map. The ADS168 uses four sequential host system I/O locations starting at the
base address, as determined by the W3 jumper block (Refer to section 2.2.1). Memory mapping
is not supported. The four special function registers and the FIFO interface that occupy the four
address locations are shown in Table 3.1. The registers at offset 0 and 1 are used for both
input and output data. The FIFO is read - only from the ISA bus.
Power -On Initialization. After the host system generates a power-on reset (POR) signal, all of
the analog output channels will be init ialized to 0 VDC and the board will enter an idle mode. The
board must be initialized after the hardware reset before any of the analog or digital functions can
be used. To initialize the board, a standard mode reset command (section 3.5), followed by an
analog output initialization command (section 3.6) should be sent to the board.
I/O Address Register
Data
Direction Function
addr + 0 INP DATA Write 8 bit data transfer register
addr + 0 OUT DATA Read 8 bit data transfer register
addr + 1 COMMAND Write Command register
addr + 1 STATUS Read Status register
addr +2 or addr +3 FIFO Read 256 byte output data FIFO
Table 3.1 - I/O address map
STATUS register
7 6 5 4 3 2 1 0
1 0 0 0 0 RH IBF OBF
Table 3.2
- STATUS register flags
The Status Register. Before commands or data can be written into the COMMAND or INP
DATA registers, the input buffer full (IBF) flag must be clear. Before sending data to these
registers, read the STATUS register (Table 3.2) until bit 1 is reset. If data is written to the board
while the IBF flag is set, data may be lost, or the board may perform in an unpredictable m anner.
The RH and OBF flags are detailed in other sections of this manual. Bit 7 will always be set and
can be used to identify the board as an ADS168. When reading a Robotrol ADA88, bit 7 will
always be cleared.
COMMAND register
7
6
5
4
3
2
1
0
0
0
1
1
0
0
1
0
Table 3.3 - Software reset (cleared outputs)
Standard Mode Reset. In the standard reset mode, a software reset command should precede
all other commands, after power-on reset or when restarting the board. There are two forms of
the standard mode software reset command - cleared analog outputs and analog outputs remain
unchanged. Writing a 30H or 31H to the COMMAND register (Table 3.3) will cause the board to
enter a reset state, without clearing the analog outputs. Writing a 32H to the COMMAND register
will cause the board to enter a reset state, with the anal og outputs cleared to 0 VDC. A 30H, 31H

ADS168 Analog Industrial Interface Board
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or 32H software reset command can be used at any time. The reset action of the 30H and 31H
commands are identical.
Board Initialization. Once the board has been reset, it will need to be initialized with the anal og
output channel update configuration. To initialize the analog outputs, determine the number of
the last analog output channel that needs to be updated , from 0 to 7, for a total of eight channels .
Write this value to the COMMAND register, only after a software or hardware reset. Note that the
IBF flag will need to be checked, prior to writing the initialization command byte to the board . The
maximum channel number (0 to 7) determines how many of the analog outputs are to be
refreshed by the on-board microprocessor. The lower the maximum number, the higher the
possible update rate. The allowable values for the channel numbers are 00H through 07H.
COMMAND register
7 6 5 4 3 2 1 0
0 0 0 0 0 n n n
Table 3.4- Analog output initialization
Compatibility Mode Reset. Another reset mode is available to maintain backward compatibility
with software written for earlier Robotrol ADA88 boards. Like the standard mode reset, there are
two forms of the compatibility mode software reset command - cleared analog outputs and analog
outputs remain unchanged. Writing a 01H to the COMMAND register will cause the board to
enter a reset state, without clearing the analog outputs. Writing a 03H to the COMMAND register
will cause the board to enter a reset state, with the analog outputs cleared to 0 VDC. An 01H or
03H software reset command can be used only after the board has been initialized with an
initialization command byte. It is not recommended that the 01H or 03H software reset
commands be used for new software designs. Note that the compatibility mode reset can only be
used after the board has been initialized with an initialization command, following a power- on
reset.
Analog Input Programming. The ADS168 has two analog input modes. In the single
conversion mode, the board does one analog conversion per command. In the c ontinuous
conversion mode, selected input channels are continuously scanned and converted. The
continuously converted values are loaded into the bus interface FIFO when commanded.
Single Conversion Mode. When a single analog input conversion is to be performed, a
command byte, containing the command mode bits (D6, D7), the gain setting for the channel (D4,
D5) and the analog input channel number (D0-D3), is written to the command register. Gain
values of X1, X2, X4 and X8 can be selected as shown in t he following table.
COMMAND register
7 6 5 4 3 2 1 0
0 1 G1
G2
MSB - - LSB
Gain
X1
0 0
Channel Number
X2
0 1
X4
1 0
X8
1 1
Table 3.5 - Analog Input Command
Once the conversion is complete, a 02H is loaded into the OUT DATA register, indicating that
there are two data bytes in the bus interface FIFO (Table 3.6). The first FIFO data byte contains
the channel number and the LSB data from the A/D conversion. The second FIFO data byte
contains the MSB data from the A/D conversion. The OBF flag of the STATUS register is then
set, and an ISA bus interrupt is generated, if enabled. Data can be read from the FIFO at
anytime, once the OBF flag has been set. The OBF flag and the ISA interrupt are cleared upon

ADS168 Analog Industrial Interface Board
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the OUT DATA register being read. Data in the FIFO will be overwritten, once a new conversion
command is requested.
OUT DATA register
7 6 5 4 3 2 1 0
0 0 MSB - - - - LSB
Byte Count in FIFO (02H)
FIFO (1st byte)
7 6 5 4 3 2 1 0
D3 D2 D2 D0 MSB - - LSB
Conversion Data Channel Number
FIFO (2nd byte)
7 6 5 4 3 2 1 0
D11 D10 D9 D8 D7 D6 D5 D4
Conversion Data
Table 3.6- Single Conversion Data
The recommended program sequence for a single channel analog input conversion is:
1. Read the STATUS register until the IBF flag is cleared.
2. Load the COMMAND register with the single conversion command byte.
3. Poll the STATUS register, checking the OBF flag or wait f or an ISA interrupt.
4. Read the OUT DATA register to get the number of bytes in the FIFO. This action will clear the
OBF flag.
5. Read the FIFO to get the LSB of the conversion data.
6. Read the FIFO to get the MSB of the conversion data.
Continuous Conversion Mode. The ADS168 can be programmed to selectively scan the
analog inputs continuously. Each channel to be scanned must be sent to the board by an
individual continuous conversion command. The command format is similar to the single
conversion mo de command, with the exception of the command bits (D6, D7).
COMMAND register
7 6 5 4 3 2 1 0
1 1 G1 G2 MSB - - LSB
Gain X1 0 0
Channel Number
X2 0 1
X4 1 0
X8 1 1
Table 3.7- Continuous Conversion Command
Each continuous conversion command sent to the board adds an analog input channel, and a
gain setting for that channel, to an internal list of inputs to be scanned and updated. This allows
inactive or unused channels to be skipped during the scanning process. Once all of the desired
channels have been sent to the board, a single command will cause the ADS168 to load the FIFO
with the conversion data for each of the se lected channels.
COMMAND register
76543210
00010000
Table 3.8
- Load FIFO Command