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FUJITSU DL3800 User Manual

Page 217

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Interface

D-5

User's Manual

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).

INTERFACE INFORMATION

#D Appendix D

2000.09.20, 2:47 PM

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