Aeroflex Circuit Technology

3

SCDCT2561 REV A 8/16/99 Plainview NY (516) 694-6700

Table 1A – Pin Function Table (78 Pin Plug-In)

Pin #

Symbol

I/O

Description

1

RT/BC

I

Mode Select input - logic "1" for RT mode, logic “0” for BC mode.

2

MT

I

Monitor mode enable. When unit is operating as a BC, a logic “0” will select

monitor mode.

3

STATEN

O

Output signal in RT mode that indicates status word is being transferred on the

internal bus.

4

TIMEOUT

O

Indicates No Response Timeout has occurred during BC and RTU (RT to RT

transfer).

5

HSFAIL

O

Output in RT mode indicating the DMA transfer did not occur in time to allow

proper operation on the 1553 bus.

6

DBACCEPT

I

Input signal used to set DBACCEPT bit in status register for response to a valid

mode command on the 1553 bus.

7

SSFLAG

I

Input which controls the SSFLAG bit in the status register.

8

SVCREQ

I

Input which controls the service request bit in the status word.

9

INCMD

O

Output signal indicating the RT is currently in a message transfer sequence.

10

SSER

I

Input which controls the subsystem error bit in the status register.

11

TESTOUT

-

Factory test point. Do not connect.

12

WC1

O

WC bit 1 - latched output of command word.

13

WC3

O

WC bit 3 - latched output of command word.

14

TXINH B

O

Transmitter inhibit output for channel B.

15

T/R

O

Output indicating T/R bit of current command word in RT mode.

16

CHA/CHB

O

Output indicating current selected channel (0 = Channel A).

17

CS

O

Chip Select output for subsystem memory control.

18

OE

O

Output Enable output for subsystem memory control.

19

BUSREQ

O

Output signal used to initiate transfer to/from subsystem.

20

+5V

I

+5 Volt DC input.

21

DB0(LSB)

I/O

Least significant bit - 16 bit parallel data bus.

22

DB2

I/O

Bit 2 of data bus.

23

DB4

I/O

Bit 4 of data bus.

24

DB6

I/O

Bit 6 of data bus.

25

DB8

I/O

Bit 8 of data bus.

26

DB10

I/O

Bit 10 of data bus.

27

DB12

I/O

Bit 12 of data bus.

28

DB14

I/O

Bit 14 of data bus.