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FUJITSU DL3750+/3850+ User Manual

Page 207

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D-5

User's Manual

INTERFACE INFORMATION

Interface

Pin

Return

Signal

Direc-

Description

No. Pin No.

name

tion

14

Host Busy

Input

Reverse data transfer phase:

This signal is set low when the

host can receive data, and goes

high when the host has received

data. Following a reverse data

transfer, the interface enters the

reverse idle phase when the Host

Busy signal goes low and the

printer has no data.

Reverse idle phase:

This signal goes high when the

Printer Clock signal goes low so

that the interface re-enters the

reverse data transfer phase. If it

goes high with the 1284 Active

signal low, the 1284 idle phase is

aborted and the interface returns

to the compatibility mode.

32

Data Available

Output

Reverse data transfer phase:

This signal is set low when the

printer is ready to send data to

the host. During the data

transfer, it is used as data bit 0

(LSB), then data bit 4.

Reverse idle phase:

This signal is used to indicate

that data is available.

36

1284 Active

Input

This signal goes high to cause the

printer to enter the reverse data

transfer phase (nibble mode).