SPRT SP-POS88VBT, User Manual, Page: 10 / 20

2 TXD Output Printer Printer transmits control
code X-ON/X-OFF and data
to host
3 RXD Input Host Printer receives data from
host
4 RTS Output Printer The same with 20pins DTR
signal
6 DSR Input Host Signal “MARK” means the
host is busy and can not
receive data. Signal
“SPACE” means the host is
ready to receive data.
7 GND —— —— Signal Ground
20 DTR Output Printer Signal “MARK” means the
host is busy and can not
receive data. Signal
“SPACE” means the host is
ready to receive data.
Fig. 2-3 The pin assignment of serial interface
Note: (1)“Source” denotes the source that signal come from;