User`s manual

BD2-2860 User’s Manual
CITIZEN
20
7.2 Explanation of Input / Output signals
(1) RXD
Serial receiving data signal. On occurrence of framing error, overrun error, or parity error, the data is
printed as "?".
(2) DTR
When this signal is READY, write data or a command. When they are written in BUSY, overrun error is
occurred and data is ignored. Even during printing, data can be loaded in the input buffer. Further, BUSY
can take place on supply of power, during test printing, during on-line, or on resetting.
(3) TXD
When, while in data reception, the rest of input buffer on the printer side goes less than 256 bytes , DC3
(13H) data reception impossible signals are output, when the rest of input buffer goes more than 256 bytes,
DC1 (11H) data reception possible signals are output to the host.
When DTR/DSR control having been selected in status information transmission, it is first confirmed that
DSR is "space" and data is sent.
When DTR/DSR control has not been selected, DSR is ignored and data is transmitted.
(4) GND
Common GND on the circuit.