Filter
Top Products
GENERAL DESCRIPTION
Rev. B
1-
2
3
1.3.5 Interface Selection
The printer has three interfaces; the parallel interface, serial interface, and optional Type-B interface.
These interfaces are selected manually by DIP SW or selected automatically.
Manual selection:
One of three interfaces can be selected by DIP SW setting.
Automatic selection:
The automatic interface selection is enabled by DIP SW setting. In this automatic interface
selection mode, the printer is initialized to the idle state scanning which interface receives data
when it is powered on. Then the interface that receives data first is selected. When the host stops
data transfer and the printer is in stand-by state for the seconds specified by DIP SW setting, the
printer is returned to the idle state. As long as the host sends data or the printer interface is busy
state, the selected interface is let as it is.
Interface state and interface selection:
When the parallel interface is not selected, the interface got into a busy state. When the serial
interface is not selected, the interface sends X-OFF and sets the DTR signal MARK. When the
optional interface is not selected, the printer sends disable commands to the optional interface.
When the printer is initialized or returned to the idle state, the parallel interface got into a ready
state, the serial interface sends X-ON and sets the DTR SPACE and the printer sends enable
commands to the optional interface.
Caution that the interrupt signal such as a /INIT signal on the parallel interface is not effective
while that interface is not selected.
1.3.6 Prevention Hosts from Data Transfer Time-out
Generally, hosts abandons data transfer to peripherals when a peripheral is in busy state for dozens of
seconds continuously. To prevent hosts from this kind of time-out, the printer receives data very slowly,
several bytes per minute, even if the printer is in busy state. This slowdown is started when the rest of the
input buffer becomes several hundreds of bytes. At last, when the input buffer is full, the printer is in busy
state continuously.