Acces 104-QUAD-6 User manual

10623 Roselle Street, San Diego, CA 92121 [phone] Fax [phone]
[email protected] www.accesio.com
MODEL 104-QUAD-8
MODEL 104-QUAD-6
MODEL 104-QUAD-4
EIGHT, SIX AND FOUR CHANNEL
QUADRATURE INPUT
PC/104 BOARDS
USER MANUAL
File: M104-QUAD-8.D1d

Manual 104-QUAD-8
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Notice
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 USA. Copyright 2002, 2005 by ACCES I/O Products, Inc. 10623 Roselle Street, San Diego, CA 92121.
All rights reserved.
WARNING!!
ALWAYS CONNECT AND DISCONNECT YOUR FIELD CABLING WITH THE
COMPUTER POWER OFF. ALWAYS TURN COMPUTER POWER OFF
BEFORE INSTALLING A BOARD. CONNECTING AND DISCONNECTING
CABLES, OR INSTALLING BOARDS INTO A SYSTEM WITH THE COMPUTER
OR FIELD POWER ON MAY CAUSE DAMAGE TO THE I/O BOARD AND WILL
VOID ALL WARRANTIES, IMPLIED OR EXPRESSED.

Manual 104-QUAD-8
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Warranty
Prior to shipment, ACCES equipment is thoroughly inspected and tested to applicable specifications. However,
should equipment failure occur, ACCES assures its customers that prompt service and support will be available.
All equipment originally manufactured by ACCES which is found to be defective will be repaired or replaced
subject to the following considerations.
Terms and Conditions
If a unit is suspected of failure, contact ACCES' Customer Service department. Be prepared to give the unit model
number, serial number, and a description of the failure symptom(s). We may suggest some simple tests to confirm
the failure. We will assign a Return Material Authorization (RMA) number which must appear on the outer label of
the return package. All units/components should be properly packed for handling and returned with freight prepaid
to the ACCES designated Service Center, and will be returned to the customer's/user's site freight prepaid and
invoiced.
Coverage
First Three Years: Returned unit/part will be repaired and/or replaced at ACCES option with no charge for labor or
parts not excluded by warranty. Warranty commences with equipment shipment.
Following Years: Throughout your equipment's lifetime, ACCES stands ready to provide on-site or in-plant service
at reasonable rates similar to those of other manufacturers in the industry.
Equipment Not Manufactured by ACCES
Equipment provided but not manufactured by ACCES is warranted and will be repaired according to the terms and
conditions of the respective equipment manufacturer's warranty.
General
Under this Warranty, liability of ACCES is limited to replacing, repairing or issuing credit (at ACCES discretion) for
any products which are proved to be defective during the warranty period. In no case is ACCES liable for
consequential or special damage arriving from use or misuse of our product. The customer is responsible for all
charges caused by modifications or additions to ACCES equipment not approved in writing by ACCES or, if in
ACCES opinion the equipment has been subjected to abnormal use. "Abnormal use" for purposes of this warranty
is defined as any use to which the equipment is exposed other than that use specified or intended as evidenced by
purchase or sales representation. Other than the above, no other warranty, expressed or implied, shall apply to
any and all such equipment furnished or sold by ACCES.

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TABLE OF CONTENTS
Chapter 1: Introduction..............................................................................................................5
Features...................................................................................................................................................................5
Applications ............................................................................................................................................................5
Functional Description...........................................................................................................................................5
Figure 1-1: Block Diagram ..................................................................................................................................6
Ordering Guide .......................................................................................................................................................6
Model Options.........................................................................................................................................................6
Included with your board.......................................................................................................................................7
Optional Accessories.............................................................................................................................................7
Chapter 2: Installation................................................................................................................8
CD Installation.........................................................................................................................................................8
Windows..............................................................................................................................................................8
Linux....................................................................................................................................................................8
Installing the Hardware..........................................................................................................................................9
To Install the Board................................................................................................................................................9
Figure 2-1: PC/104 Key Information....................................................................................................................9
Chapter 3: Option Selection ....................................................................................................10
Figure 3-1: Setup Configuration Map................................................................................................................10
Chapter 4: Address Selection..................................................................................................11
Table 4-1: Hex Ranges......................................................................................................................................11
Table 4-2: Hex Conversion Table......................................................................................................................12
Chapter 5: Programming..........................................................................................................13
Table 5-1: Base Address Map...........................................................................................................................13
Data Registers (0, 2, 4, 8, A, C, E)h:....................................................................................................................14
Control Registers (1, 3, 5, 7, 9, B, D, F)h:...........................................................................................................14
Reading the FLAG Register:................................................................................................................................14
Writing to the RLD (Reset and Load Signal Decoders): ...................................................................................15
Writing to the CMR (Counter Mode Register):...................................................................................................15
Writing to the IOR (Input / Output Control Register): .......................................................................................15
Writing to the IDR (Index Control Register):......................................................................................................16
Working with Interrupts:......................................................................................................................................16
Reading the Interrupt Status Register (10h) ......................................................................................................16
Writing to the Channel Operation Register (11h)..............................................................................................16
Writing to the Index / Interrupt Register (12h) ...................................................................................................17
Reading Index Input Levels (16h) .......................................................................................................................17
Reading Differential Encoder Cable Status (17h)..............................................................................................17
Reading the CPLD Revision Register (18h).......................................................................................................17
Sample Code (C:DOS / debug.exe).....................................................................................................................18
Chapter 6: Connector Pin Assignments.................................................................................19
Table 6-1: Connector Pin Assignments - P2 ....................................................................................................19
Table 6-2: Connector Pin Assignments - P3 ....................................................................................................20
Chapter 7: Specification...........................................................................................................21
Customer Comments ...............................................................................................................22

Manual 104-QUAD-8
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Chapter 1: Introduction
Features
Up to eight quadrature encoders may be connected
Input conditioning per channel allows a variety of encoder types to be used
Interrupt for an encoder index is program enabled per channel
Outputs to computer can include count, direction of movement
24 bit counters for each input channel
+5V supply available to the user
Applications
Automatic Test Systems
Laboratory Automation
Robotics
Machine Control
Security Systems
Energy Management
Functional Description
The card is a general purpose Quadrature Encoder Counter/Interface board. It is provided in the
popular PC/104 format and conditions and monitors the outputs of 8 encoders.
Available functions include anything that can be programmed into the versatile LSI/CSI LS7267
integrated circuit. Core functions handled by the LS7267 includes direction and total count. By
performing these functions on-board, it frees the computer for higher level applications.
The ability to provide an interrupt for the index frees the computer from the necessity of constantly
reading the position of an encoder.
Interrupts are directed to levels #2 through #7, #10 through #12, and #15 by jumper installation.
The card is designed for industrial applications. Each input line is buffered and capable of accepting
inputs up to 6 volts. A +5 Volt source is available to provide power for many encoder types.
The conditioned inputs are connected to associated LSI/CSI LS7267 integrated circuits. These circuits
are the heart of the card’s operation. We strongly recommend reviewing the manufacturer’s data sheet
for detailed information.
The card occupies 32 bytes of I/O address space. The base address is selectable via jumpers
anywhere within the range of 100-3E0 hex. An illustrated setup program is provided with the card.
Interactive displays show locations and proper settings of jumpers to set up board address and interrupt
levels.

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Figure 1-1: Block Diagram
Ordering Guide
104-QUAD-8 Eight-channel quadrature decoder PC/104 board
104-QUAD-6 Six-channel quadrature decoder PC/104 board
104-QUAD-4 Four-channel quadrature decoder PC/104 board
Model Options
-T Extended operating temperature of -40to +85C
-RoHS This product is available in a RoHS compliant version. Please call for specific
pricing then be sure to add this suffix to the model number on any hard-copy or
verbal purchase orders.

Manual 104-QUAD-8
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Included with your board
The following components are included with your shipment, depending on options ordered. Please take
the time now to ensure that no items are damaged or missing.
PC/104 quadrature board
Optional Accessories
C104-34F-12 Ribbon cable assembly, 12” with 34 pin female headers on each end
STB-34 Screw terminal board, 34 pin male header
DIN-SNAP6 DIN-rail mounting for one STB-34
104-HDW-KIT(x) PC/104 mounting hardware kit includes standard 4/40 (x=S for standard),
(x=M for metric) standoffs and pan-head Phillip screws for securing into
PC/104 stack

Manual 104-QUAD-8
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Chapter 2: Installation
A printed Quick-Start Guide (QSG) is packed with the board for your convenience. If you’ve already
performed the steps from the QSG, you may find this chapter to be redundant and may skip forward to
begin developing your application.
The software provided with this PC/104 Board is available for download from the product page on our
website at http://ACCES.IO/Downloads. It is also optionally available for a nominal cost on CD (must specify
when ordering product) and must be installed onto your hard disk prior to use. To do this, perform the
following steps as appropriate for your operating system. Substitute the appropriate drive letter for your
CD-ROM where you see d: in the examples below.
CD Installation
The following instructions assume the CD-ROM drive is drive “D”. Please substitute the appropriate
drive letter for your system as necessary.
Windows
1. Place the CD into your CD-ROM drive.
2. The system should automatically run the install program. If the install program does not run
promptly, click START | RUN and type , click OK or press .
3. Follow the on-screen prompts to install the software for this board.
Linux
1. Please visit https://github.com/accesio/Linux_PC104_legacy for Linux support for this board
family. Also, you may refer to linux.htm on the optional CD-ROM for information on installing
under linux.

Manual 104-QUAD-8
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Installing the Hardware
Before installing the board, carefully read Chapter 3 and Chapter 4 of this manual and configure the
board according to your requirements. The SETUP Program can be used to assist in configuring
jumpers on the board. Be especially careful with Address Selection. If the addresses of two installed
functions overlap, you will experience unpredictable computer behavior. To help avoid this problem,
refer to the FINDBASE.EXE program installed from the CD. The setup program does not set the options
on the board, these must be set by jumpers.
To Install the Board
1. Install jumpers for selected options and base address according to your application
requirements, as mentioned above.
2. Remove power from the PC/104 stack.
3. Assemble standoff hardware for stacking and securing the boards.
4. Carefully plug the board onto the PC/104 connector on the CPU or onto the stack, ensuring
proper alignment of the pins before completely seating the connectors together.
5. Install I/O cables onto the board’s I/O connectors and proceed to secure the stack together or
repeat steps 3-5 until all boards are installed using the selected mounting hardware.
6. Check that all connections in your PC/104 stack are correct and secure then power up the
system.
7. Run one of the provided sample programs appropriate for your operating system that was
installed from the CD to test and validate your installation.
Figure 2-1: PC/104 Key Information

Manual 104-QUAD-8
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Chapter 3: Option Selection
The only selections necessary to setup on the card are the card’s base address and the differential
(DIFF) / single-ended (SE) jumpers. All other features are setup via software, except IRQ’s.
Interrupts are optional, and directed to levels #2 through #7, #10 through #12, and #15 by a jumper at
locations labeled IRQ2 through IRQ7, IRQ10 through IRQ12, and IRQ15.
For PCB Revision C1 and newer, the “Input Mode Select”for encoder output type has 3 jumpers per
channel, 1 each for A, B & Z (Index).
From the center jumper post to the “SE” position applies 1.4V to receiver low inputs.
From the center jumper post to the “DIFF” position applies 1KΩ Termination between high and
low inputs and completes open wire detection circuitry.
Figure 3-1: Setup Configuration Map

Manual 104-QUAD-8
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Chapter 4: Address Selection
The card occupies 32 bytes of I/O space. The card base address can be selected anywhere within the
I/O address range 100-3E0 hex. If in doubt of where to assign the base address, refer to the table below
and the FINDBASE program.
HEX RANGE
USAGE
000-00F
020-021
040-043
060-06F
070-07F
080-09F
0A0-0BF
0C0-0DF
0F0-0F1
0F8-0FF
170-177
1F0-1F8
200-207
238-23B
23C-23F
278-27F
2B0-2BF
2C0-2CF
2D0-2DF
2E0-2E7
2E8-2EF
2F8-2FF
300-30F
310-31F
320-32F
370-377
378-37F
380-38F
3A0-3AF
3B0-3BB
3BC-3BF
3C0-3CF
3D0-3DF
3E8-3EF
3F0-3F7
3F8-3FF
8237 DMA Controller 1
8259 Interrupt
8253 Timer
8042 Keyboard Controller
CMOS RAM, NMI Mask Reg, RT Clock
DMA Page Register
8259 Slave Interrupt Controller
8237 DMA Controller 2
Math Coprocessor
Math Coprocessor
Fixed Disk Controller 2
Fixed Disk Controller 1
Game Port
Bus Mouse
Alt. Bus Mouse
Parallel Printer
EGA
EGA
EGA
GPIB (AT)
Serial Port
Serial Port
Hard Disk (XT)
Floppy Controller 2
Parallel Printer
SDLC
SDLC
MDA
Parallel Printer
VGA EGA
CGA
Serial Port
Floppy Controller 1
Serial Port
Table 4-1: Hex Ranges

Manual 104-QUAD-8
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The board’s base address is set up by JUMPERS. Those jumpers control address bits A5 through A9.
(Lines A4, A3, A2, A1 and A0 are used on the board to control individual registers. How these four lines
are used is described in the Programming section of this manual.)
To determine how to set these JUMPERS for a desired hex-code address, refer to the SETUP program
provided with the board. If you prefer to determine proper jumper settings yourself, first convert the hex-
code address to binary form. Then, for each "0", install corresponding jumpers and for each "1", remove
the corresponding jumper.
The following example illustrates jumper selection corresponding to hex 300 (or binary 11
000x xxxx). The "x xxxx" represents address lines A4, A3, A2, A1, and A0 used on the board
to select individual registers as described in the Programming section of this manual.
Base Address in Hex Code
3
0
Conversion Factors
2
1
8
4
2
Binary Representation
1
1
0
0
0
Jumper Legend
A9
A8
A7
A6
A5
Addr. Line Controlled
A9
A8
A7
A6
A5
Jumper Selection
OFF
OFF
ON
ON
ON
Table 4-2: Hex Conversion Table
Carefully review the address selection reference table on the preceding page before selecting the board
address. If the addresses of two installed functions overlap, you will experience unpredictable computer
behavior.

Manual 104-QUAD-8
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Chapter 5: Programming
The card is an I/O-mapped device that is easily configured from any language and any language can
easily perform quadrature reads. This is especially true if the form of the data is byte or word wide. All
references to the I/O ports would be in absolute port addressing. However, a table could be used to
convert the byte or word data ports to a logical reference.
Please refer to the chip-specification for the LS7267 in addition to this user manual for guidance
and information helpful to write device drivers for it (this spec sheet is on the software CD located in
“ChipDocs”), Also, the source code for Windows shows how to write device drivers for this product.
Address
Port Assignment
Operation
Device
Base Address
Channel 1 Data
Read/Write
First LS7267
Base Address +1
Channel 1 Flag / Command
Read/Write
Base Address +2
Channel 2 Data
Read/Write
Base Address +3
Channel 2 Flag / Command
Read/Write
Base Address +4
Channel 3 Data
Read/Write
Second LS7267
Base Address +5
Channel 3 Flag / Command
Read/Write
Base Address +6
Channel 4 Data
Read/Write
Base Address +7
Channel 4 Flag / Command
Read/Write
Base Address +8
Channel 5 Data
Read/Write
Third LS7267
Base Address +9
Channel 5 Flag / Command
Read/Write
Base Address +A
Channel 6 Data
Read/Write
Base Address +B
Channel 6 Flag / Command
Read/Write
Base Address +C
Channel 7 Data
Read/Write
Fourth LS7267
Base Address +D
Channel 7 Flag / Command
Read/Write
Base Address +E
Channel 8 Data
Read/Write
Base Address +F
Channel 8 Flag / Command
Read/Write
Base Address +10
Interrupt Status Register
Read Only
CPLD
Base Address +11
Channel Operation Register
Read/Write
Base Address +12
Index/Interrupt Register
Read/Write
Base Address +13
Reserved for Factory Use
N/A
Base Address +14
Reserved for Factory Use
N/A
Base Address +15
Reserved for Factory Use
N/A
Base Address +16
Index Input Levels
Read Only
Base Address +17
Differential Encoder Cable Status
Read/Write
Base Address +18
CPLD Revision
Read Only
Base Address +19 through +1F
Reserved for Factory Use
N/A
Table 5-1: Base Address Map

Manual 104-QUAD-8
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Data Registers (0, 2, 4, 8, A, C, E)h:
These registers are read to retrieve the current count from the channel, and written to set the Preset
Register and the Filter Clock Prescalers.
To get the count from Channel 1 (Data register 0) you would first write 11h to the control register at
address 1. Three reads are then required to get the current count from data register 0. The first read
returns the Least Significant Byte and the last read returns the Most Significant Byte.
In order to write to the Preset Register first write 11h to the control register. Then perform three writes to
the data register. The first write is the Least Significant Byte, and the last write is the Most Significant
Byte.
In order to write to the Filter Clock Prescaler first write 11h to the control register. Then write one byte
to the data register with the desired PSC value. Then write 19h to the control register.
Control Registers (1, 3, 5, 7, 9, B, D, F)h:
The control registers all correspond to the data register that is one address below it.
The control register is used for the following operations:
Reading the Flag Register;
Resetting the BP (three byte data pointer) and flags;
Setting the PSC (filter clock factor n) and PR (preset count);
Initial setup of the Counter Mode Register, Input/Output Control Register and Index Control
Register.
Reading the FLAG Register:
Bit 0 BT: Borrow Toggle flip-flop. Toggles every time the counter underflows.
Bit 1 CT: Carry Toggle flip-flop. Toggles every time the counter overflows.
Bit 2 CPT : Compare Toggle flip-flop. Toggles every time the counter is equal to the Preset
Register.
Bit 3 S: Sign flag. Set to 1 when counter underflows and reset to 0 when it overflows.
Bit 4 E: Error flag. Set to 1 when excessive noise is present at the count inputs in
quadrature mode. Ignore in other modes.
Bit 5 U/D: Up/Down flag. Set to 1 when counting up and reset to 0 when counting down.
Bit 6 IDX: Index. Set to 1 when selected index input is at active level.
Bit 7: Not used is always 0.

Manual 104-QUAD-8
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Writing to the RLD (Reset and Load Signal Decoders):
Bit 0: 1 to reset BP.
Bits 1 & 2: Set bit 1 high to reset CNTR, set bit 2 high to reset BT, CT, CPT, S flags.
Set both bits high to reset E flag.
Bits 3 & 4: Set bit 3 high to transfer Preset Register to Counter.
Set bit 4 high to transfer CNTR to Output Latch.
Set both high to transfer Preset Register LSB to the PSC (FCK Prescaler).
Bits 5 & 6: Set both bits to 0.
Bit 7: Set high to program both counters simultaneously.
Writing to the CMR (Counter Mode Register):
Bit 0: Set low to use Binary count, and set high to use BCD count.
Bits 1 & 2: Set both low to use Normal count.
Set bit 1 high to use Range Limit.
Set bit 2 high to use Non-Recycle count.
Set both bits high to use Modulo-N count.
Bits 3 & 4: Set both bits low to use non-quadrature mode.
Set bit 3 high to use Quadrature times 1.
Set bit 4 high to use Quadrature times 2.
Set both bits high to use Quadrature times 4.
Bits 5 & 6: Set bit 5 high and bit 6 low.
Bit 7: Set high to program both counters simultaneously.
Writing to the IOR (Input / Output Control Register):
Bit 0: Set high to enable A and B inputs.
Bit 1: Set low to preset count when Index occurs.
Set high to continuously count.
Bit 2: Set low.
Bits 3 & 4: Set both bits low to use FLG1 as /Carry (active low).
Set bit 3 high to use FLG1 as /Compare (active low).
Set bit 4 high to use FLG1 as /Carry/Borrow (active low).
Set both bits high to use FLG1 as Index (active high).
Bits 5 & 6: Set bit 5 low and bit 6 high.
Bit 7: Set high to program both counters simultaneously.
Note that when Interrupts are enabled on the card they occur whenever FLG1 is active.

Manual 104-QUAD-8
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Writing to the IDR (Index Control Register):
Bit 0: Set high to enable index.
Bit 1: Set high for a positive index polarity.
Set low for a negative index polarity.
Bit 2: Set low.
Bits 3 & 4: Not used.
Bits 5 & 6: Set high.
Bit 7: Set high to program both counters simultaneously.
Working with Interrupts:
Reading the Interrupt Status Register (10h)
When an interrupt occurs read from address 10h to determine which channel was the source.
Bit 0-7: The Least Significant Bit will correspond to the first channel.
High = true
Writing to the Channel Operation Register (11h)
Any write to this address will clear any pending interrupts.
A read from this address will return it’s contents.
Bit 0: Set high to reset all Counters.
Set low to enable all Counters.
Bit 1: Reserved.
Bit 2: Set low to disable the interrupt function.
Set high to enable the interrupt function.
Bits 3-7: Reserved.

Manual 104-QUAD-8
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Writing to the Index / Interrupt Register (12h)
This register is used to Preset Counter via the LCNTR input pin when a channel index
occurs as described in Writing to the IOR and Writing to the IDR.
Additionally it is used to generate interrupts whenever FLG1 on a channel is active as
described in Writing to the IOR and Writing to the Channel Operation Register.
Each bit of this register enables / disables a corresponding channel.
A read from this address will return it’s contents.
Bit 0: Set high to enable Channel 1
Bit 1: Set high to enable Channel 2
Bit 2: Set high to enable Channel 3
Bit 3: Set high to enable Channel 4
Bit 4: Set high to enable Channel 5
Bit 5: Set high to enable Channel 6
Bit 6: Set high to enable Channel 7
Bit 7: Set high to enable Channel 8
Reading Index Input Levels (16h)
Bit 0 through 7 correspond to channels 1 through 8.
Logic 0 = Index Input low (false).
Logic 1 = Index Input high (true).
*If your encoder does not have an Index signal, the Index Positive Input pin needs to be
grounded or the corresponding channel bit will return a logic 1 level.
Reading Differential Encoder Cable Status (17h)
Bit 0 through 7 correspond to channels 1 through 8.
To enable any channel write a 0 to the corresponding bit.
When enabled, Logic 0 = cable fault (not connected or loose wires).
Logic 1 = cable connection good or cable fault disabled (default).
Bits 0 through 7 will always read a high when disabled.
Reading the CPLD Revision Register (18h)
To determine the CPLD Revision read from address 18h
Old card revisions B10 and earlier will read FF
Revision C1 cards will read 00
Revision C2 cards will read 01

Manual 104-QUAD-8
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Sample Code (C:DOS / debug.exe)
Channel 1 setup
o 301 15
o 300 00
o 300 00
o 300 00
o 301 28
o 301 59
o 301 63
o 311 05
o 311 04
o 312 01
Channel 1 data (24-bit) and flags (8-bit), card interrupt status (8-bit)
o 301 11
i 300
i 300
i 300
i 301
i 310
o 311 04
repeat above 7 commands while turning encoder

Manual 104-QUAD-8
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Chapter 6: Connector Pin Assignments
Function
CH#
Pin
Pin
CH#
Function
Ground
1
1
2
1
Fused +5V
Index Negative Input
1
3
4
1
Index Positive Input
Quadrature A Negative Input
1
5
6
1
Quadrature A Positive Input
Quadrature B Negative Input
1
7
8
1
Quadrature B Positive Input
Ground
2
9
10
2
Fused +5V
Index Negative Input
2
11
12
2
Index Positive Input
Quadrature A Negative Input
2
13
14
2
Quadrature A Positive Input
Quadrature B Negative Input
2
15
16
2
Quadrature B Positive Input
Ground
3
17
18
3
Fused +5V
Index Negative Input
3
19
20
3
Index Positive Input
Quadrature A Negative Input
3
21
22
3
Quadrature A Positive Input
Quadrature B Negative Input
3
23
24
3
Quadrature B Positive Input
Ground
4
25
26
4
Fused +5V
Index Negative Input
4
27
28
4
Index Positive Input
Quadrature A Negative Input
4
29
30
4
Quadrature A Positive Input
Quadrature B Negative Input
4
31
32
4
Quadrature B Positive Input
No connection
33
34
No connection
Table 6-1: Connector Pin Assignments - P2
Notes:
1. When using single-ended Encoders leave the Negative Input open (internal 1.4V threshold
level) and connect the Encoder (A, B, Index) output lead to the corresponding Positive Input pin.
2. Both single-ended and differential Encoders require a ground connection between the Encoder
and the PC/104 board to eliminate the adverse effects of exceeding the common mode range
when an external power supply is used.
3. When the Fused +5V source is used to power your encoders, (i.e. on pins 2, 10, 18, & 26)
Ground (i.e. on pins 1, 9, 17, & 25) is a required return path.

Manual 104-QUAD-8
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Function
CH#
Pin
Pin
CH#
Function
Ground
5
1
2
5
Fused +5V
Index Negative Input
5
3
4
5
Index Positive Input
Quadrature A Negative Input
5
5
6
5
Quadrature A Positive Input
Quadrature B Negative Input
5
7
8
5
Quadrature B Positive Input
Ground
6
9
10
6
Fused +5V
Index Negative Input
6
11
12
6
Index Positive Input
Quadrature A Negative Input
6
13
14
6
Quadrature A Positive Input
Quadrature B Negative Input
6
15
16
6
Quadrature B Positive Input
Ground
7
17
18
7
Fused +5V
Index Negative Input
7
19
20
7
Index Positive Input
Quadrature A Negative Input
7
21
22
7
Quadrature A Positive Input
Quadrature B Negative Input
7
23
24
7
Quadrature B Positive Input
Ground
8
25
26
8
Fused +5V
Index Negative Input
8
27
28
8
Index Positive Input
Quadrature A Negative Input
8
29
30
8
Quadrature A Positive Input
Quadrature B Negative Input
8
31
32
8
Quadrature B Positive Input
No connection
33
34
No connection
Table 6-2: Connector Pin Assignments - P3
Notes:
1. When using single-ended Encoders leave the Negative Input open (internal 1.4V threshold
level) and connect the Encoder (A, B, Index) output lead to the corresponding Positive Input pin.
2. Both single-ended and differential Encoders require a ground connection between the Encoder
and the PC/104 board to eliminate the adverse effects of exceeding the common mode range
when an external power supply is used.
3. When the Fused +5V source is used to power your encoders, (i.e. on pins 2, 10, 18, & 26)
Ground (i.e. on pins 1, 9, 17, & 25) is a required return path.