RS-232C Protocol
B-7
SG - Signal Ground - (Pin 7)
All signals can transmit between the printer and the host computer to send
each signal with a signal ground.
DTR - Data Terminal Ready - (Pin 20)
This output is used as a buffer nearly-full handshake line. It is held high
(above 3 volts) when the buffer can accept more data.
RS-232C Interface Voltage Levels
The voltage levels of the interface signals conform to EIA RS-232C
specifications. SPACE is from 3 volts to 15 volts. MARK is from -3 volts to
-15 volts. Voltages between -3 volts and 3 volts are undefined.
RS-232C Protocol
A protocol is a set of rules the computer follows in sending data to the
printer. The RS-232C parameters are stored in battery backed-up memory.
They are indicated on the status printout. They can be changed by the
FRPO (firmware reprogram) command described in the Programming
Manual provided on the CD-ROM supplied with the printer. The
parameters and their identification codes are given below.
H1: Baud rate
The factory setting is 9600 baud.
H2: Data bits
7 or 8, factory-set to 8.
H3: Stop bits
1 or 2, factory-set to 1.
Parameter value Baud rate
12 1200
24 2400
48 4800
96 9600
19 19200
38 38400
57 57600
11 115200
Table B-5