Tally Dascom 2810, Руководство пользователя

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User Guide Options and accessories
Protocols
Memory mode XON/XOFF
The received characters are stored in a FIFO buffer (first in/first out). The
characters are processed in this buffer.
The buffer capacity can be adjusted from 0 to 128 Kb.
If the buffer is full, the interface signals NOT READY (signal acknowledgement:
Level 1, -12 V) and XOFF (hex. 13, dec. 19). This results in stopping the data
transmission. When the FIFO buffer is empty again, the interface signals READY
(level 0, +12 V) and XON (hex. 11, dec. 17). Data transmission can be continued.
In addition, the READY signal is influenced by the status of the printer (On/Off
Line). If the printer assumes an undefined state, the interface also signals NOT
READY and XOFF.
Memory mode Robust XON/XOFF
Robust XON/XOFF is similar to XON/XOFF. However, the state of the printer
(XON or XOFF) is also periodically transmitted via the TxD line in the case of
Robust XON/XOFF.
Extended menu functions with the ENQ/STX and ETX/ACK protocols selected
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