Appendix B: Pinout Specifications

Serial Models

DB25 Female

Pin

Signal Name

Acronym

I/O

Description

2

Transmit data

TXD

Output

Serial data from port

3

Receive data

RXD

Input

Serial data to port

4

Request to send

RTS

Output

Always high

6

Data set ready

DSR

Input

Low inhibits transmit data

7

Signal ground

GND

Common

 

20

Terminal ready

DTR

output

 

Pin 20 is the hardware flow control output. Pin 6 is the hardware flow control input. Pin 6 has an internal pull-up to set it high when no signal is connected.

Parallel Models

Centronics 36 Female

DB25 Female

C36F

DB25

 

 

 

 

Pin

Pin

Signal Name

Port 0

Port 1-8

Description

1

1

STROBE

output

input

Data transfer when pulsed low

2

2

DATA 0

output

input

Data LSB

3

3

DATA 1

output

input

 

4

4

DATA 2

output

input

 

5

5

DATA 3

output

input

 

6

6

DATA 4

output

input

 

7

7

DATA 5

output

input

 

8

8

DATA 6

output

input

 

9

9

DATA 7

output

input

Data MSB

10

10

ACK

input

output

Pulsed low for next transfer

11

11

BUSY

input

output

If high inhibits data flow

12

12

PAPER END

input

output

Input unused, low when output

13

13

SELECT OUT

input

output

Input unused, high when output

14

14

AUTOFEED

output

input

Input unused, output high

16

 

GROUND

--------

--------

Wired common all ports

19-30

18-25

GROUND

--------

--------

Wired common all ports

31

16

INITIAL

output

Input

Must be high to receive data

32

15

ERROR

Input

output

Input unused, high when output

33

-

GROUND

--------

--------

Wired common all ports

36

17

SELECT IN

output

input

Must be low to receive data

CARETAKER PLUS INSTALLATION AND OPERATIONS MANUAL

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Image 35
Rose electronic Automatic Switch manual Appendix B Pinout Specifications