Turning Ideas Into Reality

ABCircuits www.abcircuits.com POB 123 New Hill NC 27562 (919) 290-7104

Part Number SIO8

Copyright © 2014 ABCircuits. Revised September 2014 Page 4 of 8

Pin Description

Pin #

Description

Pin #

Description

1

NC

28

VDD

2

NC

27

TXE

3

SPD

26

RXP

4

SOUT-

25

MODE

5

OA7

24

SIN-

6

OA5

23

OA6

7

OA3

22

OA4

8

OA1

21

OA2

9

NC

20

OA0

10

IA7

19

NC

11

IA5

18

IA6

12

IA3

17

IA4

13

IA1

16

IA2

14

VSS

15

IA0

OA0-7

These output bits are set when a byte is received on the SIN- pin. Output drivers may be

required for high power loads. The RXP pin generates a positive pulse after these bits are set.

SIN-

This is the serial input pin. It may be tied directly to the UART transmitter output of your UART or

microprocessor; to a RS -232 receiver such as the MAX232; an Ethernet interface such as the

Lantronix Xport; or a USB IC such as the FT232. This pin is high in the idle state, the input

format is 8 bits, 1 stop, no parity at 9600 BPS. Other formats and baud rates are available,

please contact the factory for information. The byte received on this pin will be transferred to the

OA0-7 pins, then a positive pulse is generated on the RXP output. This pin does not have an

internal pull up resistor. It is recommended your software periodically send the byte that is

transferred to the OA0-7 pins even if they have not changed to recover from communications

errors or power failures.

You can drive this input with any hexadecimal terminal program like REALTERM for testing and

development.

SOUT-

This is the serial output pin. It may be tied directly to the UART receiver input of your UART or

microprocessor; to a RS -232 driver such as the MAX232; an Ethernet interface such as the

Lantronix Xport, or a USB IC such as the FT232. This pin sends the data on the IA0-7 pins,

adding start and stop bits. See the description of the MODE pin to determine when this data will

be sent. This pin is high in the idle state, the output format is 8 bits, 1 stop, no parity at 9600

BPS. Other output formats and baud rates are available, please contact the factory for

information.

You can monitor this output with any hexadecimal terminal program like REALTERM. Hyperterm

does not display in hexadecimal.

IA0-7

These are the input bits that will be transmitted on the SOUT- pin. These inputs have internal pull

up resistors.