Reverse channel

Transmission mode:

IEEE-1284 Nibble mode

Adaptable connector:

57-30360 (Amphenol) or equivalent

Synchronization:

Refer to the IEEE-1284 specification

Handshaking:

Refer to the IEEE-1284 specification

Signal level:

IEEE-1284 level 1 device

Data transmission

 

 

 

 

timing:

 

Refer to the IEEE-1284 specification

Extensibility request:

The printer responds to the extensibility

 

 

request in the affirmative when the

 

 

request is 00H or 04H, which means:

 

 

00H:

Request nibble mode of reverse channel

 

 

 

transfer

 

 

 

 

04H:

Request device ID in nibble mode of

 

 

 

reverse channel transfer

The following table lists the parallel connector pin assignments and

describes their respective interface signals.

 

 

 

 

 

 

 

 

Pin no.

Signal name

GND

In/Out

Description

 

 

 

 

 

 

 

1

HostClk

19

In

Strobe pulse. Input data

 

 

 

 

 

is latched at falling

 

 

 

 

 

edge of the signal.

 

 

 

 

 

 

 

2

DATA1

20

In

Bit 0: LSB Parallel input

 

 

 

 

 

data to the printer.

 

 

 

 

 

 

 

3

DATA2

21

In

These signals represent

 

 

 

 

 

information in bits 0 to 7

 

4

DATA3

22

In

of parallel data

 

 

 

 

 

 

 

 

 

 

5

DATA4

23

In

respectively. Each signal

 

 

 

 

 

is at HIGH level when

 

6

DATA5

24

In

data is logical 1 and

 

 

 

 

 

 

7

DATA6

25

In

LOW when it is logical 0.

 

 

 

 

 

These signals are used

 

8

DATA7

26

In

to transfer the 1284

 

 

 

 

 

 

9

DATA8

27

In

extensibility request

 

 

 

 

 

values to the printer.

 

 

 

 

 

 

 

A-12Technical Specifications