Operator`s manual
4.0 Host Interface Specifications
4.1 Hardware Interface
The Unit base configuration uses an RS-232 Asynchronous Serial Communications port to interface to the Host system.
The physical connection is provided using a single DB-25 female pin connector. A simple null-modem cable connection
quickly interfaces the Unit to a standard connection on a typical PC-based host system. The pinout below provides the
basic cabling requirements to connect the Unit to a PC-type host system.
Pin number Function Source
1 Earth Ground (shield) n/a
2 Transmit Data (TxD) Printer
3 Receive Data (RxD) Host
4 Request To Send (RTS) Printer
5 Clear To Send (CTS) Host
6 Data Set Ready (DSR) Host
7 Signal Ground n/a
11 Jumper to RTS Printer
20 Data Terminal Ready (DTR) Printer
8, 9, 10, 12, 13, 14, 15, 16, 17, 18, 19,
21, 22, 23, 24, 25
No connect n/a
The connection from pin 11 to RTS enables the Unit to function with existing customer cabling. This connection can be
removed if necessary.
The Unit may also have optional hardware interfaces including parallel, dual serial, and Ethernet. Custom firmware
interfaces will be written for these and the existing serial interface.
4.2 Data Structure
The serial communications port uses an asynchronous serial data transmission method. Data is transmitted and received
based on a combination of the following possible communication parameters:
Bau
d
Data Len
g
th Parit
y
Sto
p
Bit
1200 - 115,200 7, 8 None, Even, Odd, Mark, Space 1, 2
5.0 ASCII Control Character List (some characters available with certain firmware versions only)
ACK
- Acknowledge character (06
HEX
).
CR
- Carriage Return character (0D
HEX
).
DC1
- XON character (11
HEX
). Used to indicate that the host serial port is ready.
DC3
- XOFF character (13
HEX
). Used to indicate that the host serial port is NOT ready.
ETX
- End Of Text sequence. Used to suffix data and commands being sent to and received from the Unit.
LF
- Line Feed character (0A
HEX
).
NAK
- Negative Acknowledge character (15
HEX
).
SOH
- Start Of Header character (01
HEX
). Sometimes used to prefix special commands or messages.
STX
- Start Of Text sequence. Used to prefix data and commands being sent to and received from the Unit.
ET6000 Operator’s Manual 71U-1415-100K; REV E Page 6 of 38