Access IOD-144 User Manual

ACCES I/O PRODUCTS INC

10623 Roselle Street, San Diego, CA. 92121

tel. [phone] FAX [phone]

DIGITAL INPUT/OUTPUT CARD

MODEL IOD-144

USER MANUAL

File: MIOD144.B2b

DIGITAL INPUT/OUTPUT CARD IOD-144 USER MANUAL

NOTICES

The information in this document is provided for reference only. ACCES does not assume
any liability arising out of the application or use of the information or products described
herein. This document may contain or reference information and products protected by
copyrights or patents and does not convey any license under the patent rights of ACCES,
nor the rights of others.

IBM PC, PC/XT, and PC/AT are registered trademarks of the International Business
Machines Corporation.

Printed in the USA. Copyright 1998 by ACCES I/O PRODUCTS INC, 10623 Roselle Street,
San Diego, CA 92121. All rights reserved.

DIGITAL INPUT/OUTPUT CARD IOD-144 USER MANUAL

TABLE OF CONTENTS

INSTALLATION ............................... 1-1

CD INSTALLATION ......................... 1-1

3.5-INCH DISKETTE INSTALLATION ........... 1-1

DIRECTORIES CREATED ON THE HARD DISK .. 1-2

INSTALLING THE CARD ..................... 1-4

FUNCTIONAL DESCRIPTION .................... 2-1

BLOCK DIAGRAM .......................... 2-2

OPTION SELECTION ........................... 3-1

OPTION SELECTION MAP ................... 3-2

ADDRESS SELECTION ......................... 4-1

ADDRESS ASSIGNMENTS FOR PC XT ......... 4-1

SOFTWARE .................................. 5-1

SETUP.EXE ............................... 5-1

WINDOWS UTILITY DRIVERS ................ 5-2

PROGRAMMING .............................. 6-1

PORT ADDRESS SELECTION TABLE .......... 6-1

PROGRAMMING EXAMPLE .................. 6-4

SAMPLE PROGRAMS ....................... 6-5

SHARING INTERRUPTS ON THE ISA BUS ..... 6-13

CONNECTOR PIN ASSIGNMENTS ................ 7-1

SPECIFICATIONS ............................. 8-1

WARRANTY .................................. 9-1

PPI DATA SHEETS ............................ A-2

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DIGITAL INPUT/OUTPUT CARD IOD-144 USER MANUAL

INSTALLING THE CARD

Before installing the card carefully read the ADDRESS SELECTION and OPTION
SELECTION Sections of this manual and configure the card according to your require­ments. Use the special software program called SETUP.EXE provided on diskette with
the card. It supplies visual aids to configure all areas of the board.

Be especially careful with address selection. If the addresses of two installed functions
overlap, you will experience unpredictable computer behavior. If unsure what locations
are available, you can use the FINDBASE program provided on our diskette to locate
blocks of available addresses.

To install the card:

1. Remove power from the computer.

2. Remove the computer cover.

3. Remove blank I/O backplate.

4. Install jumpers for selected options. See OPTION SELECTION section of
this manual.

5. Select the base address on the card. See ADDRESS SELECTION
section of this manual.

6. Loosen the nuts on the strain relief bar and swing top end free.

7. Install the card in an I/O expansion slot. If convenient, select a slot which
is adjacent to a vacant slot because this will make cable installation
easier.

8. Thread the I/O cables, one by one through the cutout in the mounting
bracket and plug them into the headers.

9. Smooth the cables as close as practicable to the card and while holding
them close to the card surface, swing the strain relief bar into position
and tighten nuts.

10. Inspect for proper fit of the card and cables and tighten screws. Make

sure that the card mounting bracket is properly screwed into place and
that there is a positive chassis ground.

11. Replace the computer cover.

Input/Output connections are via six 50-pin headers on the card. A blank mounting
bracket is provided with units that are marked for CE (European) Certification and, for
these units, CE-certifiable cable and break-out methodology (cables connected to
ground at the aperture, shielded twisted pair wiring, etc.) must be used.

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DIGITAL INPUT/OUTPUT CARD IOD-144 USER MANUAL

FUNCTIONAL DESCRIPTION

FEATURES

144 Channels of Digital Input/Output.
All 144 I/O Lines Buffered on the Board.
Four and Eight Bit Groups Independently Selectable for I/O.
Hysteresis Correction and Pull-Down Resistors on I/O Lines.
Interrupt and Interrupt-Disable Capability.
Tri-stateable I/O ports under software control.
+5V Supply Available to User.
Compatible with Industry Standard I/O Racks like Opto-22, Potter & Brumfield, etc.

APPLICATIONS

Automatic Test Systems.
Security Systems, Energy Management.
Robotics
Relay Monitoring and Control.
Parallel Data Transfer to PC.
Sensing switch closures or TTL, DTL, CMOS Logic.
Driving Indicator Lights or Recorders.

The IOD-144 board was designed for industrial applications and should be installed in a
long slot of an IBM PC/XT/AT or compatible computer. Each I/O line is buffered and
capable of sourcing 15mA, or sinking 24mA (64mA on request). The board contains five
Programmable Peripheral Interface chips type 8255-5 (PPI) to provide computer in­terface to 144 digital I/O lines. Each PPI provides three 8-bit ports A, B, and C. Each
8-bit port can be configured to function as either inputs or output latches. Port C can
also be configured as four inputs and four output latches. The I/O line buffers (74LS245)
are configured automatically by hardware logic for input or output use according to the
PPI 8255-5 Control Register direction software assignment.

The I/O buffers may be tristated under program control. If the BEN/TST jumper on the
card is installed in the BEN position, the I/O buffers are permanently enabled allowing
transparent backwards compatibility. However, if the jumper is placed in the TST
position, enable/disable of the buffers is possible under software control.

Two I/O lines of each port can be used for interfacing User Interrupts to the computer.
Interrupts are buffered and are enabled by jumper installation or by a combination of
jumper installation and a digital input line. You can use Interrupts #2 through #7, #10
through #12, #14 and #15. Interrupts of all ports (one per port) are OR'ed together. I/O
wiring connections are via 50-pin headers on the board. Six flat I/O cables connect

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DIGITAL INPUT/OUTPUT CARD IOD-144 USER MANUAL

IOD-144 to termination panels such as ACCES model STA-50. Also, this provides
compatibility with OPTO-22, Gordos, Potter & Brumfield, etc. module mounting racks.
Every second conductor of the flat cables is grounded to minimize the effect of crosstalk
between signals. If needed for external circuits +5VDC power is available on each I/O
connector pin 49. If you use this power, we recommend that you include a 1A fast blow
fuse in your circuits in order to avoid possible damage to the host computer.

The board occupies 24 consecutive bytes within the I/O address space. The base
address is selectable via ADDRESS SETUP DIP switches (A5-A9) anywhere within the
hex 000-3FF range.

Utility software provided on diskette with the IOD-144 card is an illustrated setup
program. Interactive displays show locations and proper settings of DIP switches and
jumpers to set up board address, interrupt levels, and interrupt enable. Additionally, two
sample programs and a utility driver for use with VisualBASIC for Windows are
provided. See the Software section of this manual for a detailed description of the latter.

IOD-144 BLOCK DIAGRAM

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DIGITAL INPUT/OUTPUT CARD IOD-144 USER MANUAL

OPTION SELECTION

Refer to the illustrated setup programs on the diskette provided with the card when
reading this section of the manual. Also, refer to the OPTION SELECTION MAP on the
following page.

Base address selection is covered both by the diskette and in the next section of this
manual.

Interrupts are accepted on the I/O connector, pin 9 (port C3). The interrupt signal is
positive true. Interrupts are unconditionally enabled if the IEN jumper is installed, or
enabled by program if the INP jumper is installed and I/O connector pin 1 (port C) is low.
Interrupts are disabled if (a) neither the IEN or INP jumper is installed, or (b) if the INP
jumper is installed but I/O connector pin 1 (port C7) is held high. User interrupts are
directed to interrupts #2 through #7, #10 through #12, #14 and #15 by jumpers installed
at locations labeled IRQ2 through IRQ15.

The foregoing are the only manual setups necessary to use the IOD-144. Input/Output
selection is done, via software, by writing to the PPI 8255-5 Control Registers as
described in the PROGRAMMING section of this manual.

IOD-144 provides a means to enable/disable the tristate I/O buffers under program
control. If the BEN/TST jumper on the card is installed in the BEN position, the I/O
buffers are permanently enabled. However, if the jumper is placed in the TST position,
enable/disable of the buffers is possible under software control via the Control Register
as described in the Software Programming section of this manual.

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DIGITAL INPUT/OUTPUT CARD IOD-144 USER MANUAL

OPTION SELECTION MAP

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DIGITAL INPUT/OUTPUT CARD IOD-144 USER MANUAL

ADDRESS SELECTION

The IOD-144 Input/Output Card occupies 24 bytes of I/O space. The card base address
can be selected anywhere within an I/O address range 000-3FF hex. If all 144 bits are
to be used in an AT-class computer, the base address can be set anywhere within the
address range hex 100-390 (except 1F0 through 1F8). If to be used in an XT-class
computer, the starting address can be as above except the lowest starting address is
200 hex.

However two installed options can not share the same address. If in doubt where to
assign the base address of the IOD-144, refer to the tables below and consult the
FINDBASE program on the utility diskette.

STANDARD ADDRESS ASSIGNMENTS FOR PC XT COMPUTERS

Hex Range Usage

000-00F
020-021
040-043
060-063
080-083
0AX
0CX
OEX
100-1FF
200-20F
210-217
220-24F
278-27F
2F0-2F7
2F8-2FF
300-31F
320-32F
378-37F
380-38C**
380-389**
3A0-3A9
3B0-3BF
3C0-3CF
3D0-3DF
3E0-3E7
3F0-3F7
3F8-3FF

DMA Chip 823 7A-5
Interrupt 8259A
Timer 8253-5
PPI 8255A -5
DMA Page Register
NMI Mask Register
Reserved
Reserved
Not Usab le
Game Control
Expa nsion Unit
Reserved
Reserved
Reserved
Asynchronous Comm 'n (Secondary)
Prototype Ca rd
Fixed Disk
Printer
SDLC Communications
Binary Synchronous C omm . (Secondary)
Binary Synchronous C omm . (Primary)
IBM Monochrome Display/Printer
Reserved
Color/Graphics
Reserved
Diskette
Asynchronous Comm 'n (Primary)

** These options can not be used together - addresses overlap

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