TallyGenicom 2440, Руководство пользователя

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Interfaces Parallel interface
B-5
Data Transmission Timing
In unidirectional mode (conventional Centronics interface), this printer guarantees the re-
ceived data when the Data and Data Strobe signals from the computer have the following
timing with respect to the Busy and Acknowledge signals from the printer.
Notes:
1) All timing are in microseconds.
2) The minimum value for T1 (printer initializing time) is TBD millisecond.
3) The minimum value for T2 (printer processing time) is TBD microsecond.
4) Printer initialization occurs at the falling edge of nINIT.
In bidirectional mode (nibblemode), this printer can send data to the computer. Data is
sent in units of four bits (nibble) using four output signal lines as data paths. The follow-
ing outlines one byte of data sent during reverse data transfer phase in nibble mode.
DATA
nSTB
nACK
BUSY
nINIT
0.5 max.
T2
0 min.
approx. 5
0 min. 0.5 min.
0.5 min. 0.5 min.
1 max.
50 min.
T1