TransAct Ithaca 8000, Programmer'S Manual

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Communications Ithaca
®
8000 Programmer’s Guide
Page 288 Rev D 100-06908
Miscellaneous Communication Features
Power-cycle Recovery
Sometimes the host needs to know if the printer was power cycled. An example would
be after the receipt tape was changed. It is not necessary to turn off the printer to
change the receipt. However, if the operator does, any information sent to the printer
before the power cycle will be lost.
The Ithaca
®
8000 Printer has a flag that is set after a reset. The flag stays set until the
host requests a reset. The [ENQ] <11> command reads the flag. If the command
returns power-cycled status, the power has been reset or power cycled since the last
request. All unprinted information has been lost.
If the print operation is critical, it is a good idea to check the power-cycle flag before and
after all transactions. An alternate approach is to check the flag after every off-line to
on-line transition.
Note: If the printer mode was changed by the [ESC] y <2> or <3> command, a power-
cycle reset will return to the initial configuration.
Data Pass-through
The Ithaca
®
8000 Printer supports data pass-through (sometimes referred to as display
pass-through). Data pass-through is activated by the print-suppress command with the
pass-through bit set. In pass-through mode, the printer can be requested to transmit any
data that it receives. When this is the case, the printer‘s inquire commands are active
but of little use. Typically, the printer‘s transmit data is connected to the next device in
line. Inquire commands have no data path back to the host. If pass-through is to be
used, it is a good idea to deactivate the inquire commands. (Use [ESC] y <6>).
Before pass-through data can be used, it must be activated in the configuration menu,
which is the third selection in the print-suppress/pass option.
All data after, but not including, the print-suppress command is pass through. When
deactivated, the print-suppress command is again not pass through. During pass
through the multi-drop commands are active (if configured).
The printer will act upon a multi-drop control command found in the pass-through data.
If the printer is deselected during pass-through, it stops passing on the data. When the
printer is re-addressed, data pass-through is active.
Multi-drop Configuration
The Ithaca
®
8000 Printer supports a multi-drop configuration where up to three printers
can be connected in parallel. Each printer has a different address A, B, or C. The
printer does not accept any print information unless it is addressed. Multi-drop
configuration is only available in serial mode, as parallel printers cannot be connected
together.