Serial Interface Protocols - Printronix P6000L User's Reference Manual

Transmit Clock (TC) - An optional timing signal for transmitted data that may be provided by
a Data Set with synchronous interface.
Receive Clock (RC) - An optional timing signal for Received Data that may be provided by a
Data Set with synchronous interface.
External Clock (EC) - An asynchronous timing clock stream pulsed at 16 times the data bit
input rate from an external TTL source when external baud rate has been selected.
INPUT SIGNALS
SIGNAL
Received Data
Clear To Send
Data Set Ready
Carrier Detect
Transmit Clock
Receive Clock
External Clock

Serial Interface Protocols

The following serial interface protocol characters are available. The protocol is configuration
selectable from the control panel to meet host interface requirements.
XON/XOFF - The printer transmits an XON (11 Hex) character when entering the online
state or when the buffer is almost empty. The printer transmits an XOFF (13 Hex) character
when entering the offline state or when the buffer is almost full.
ETX/ACK - With ETX/ACK protocol selected, the printer interface operates in a block struc
tured mode. The host sends a block of data (commonly 128 characters) in response to an ACK
(06 Hex) character sent from the printer. The host marks the end of the block of data with an
ETX (03 Hex) character. When the printer recognizes the ETX character, the printer releases
the data block to be printed and checks the space available in the buffer. If space is available for
the next block of data, the printer sends ACK to the host. If space is not available, the printer
withholds ACK until sufficient space is available.
ACK/NAK - With ACK/NAK protocol selected, the printer responds as described for ETX/
ACK protocol except the printer monitors the received data for parity error. If a parity error is
7-6
Table 7-3. Serial Interface Pin Assignments
PIN
3
5
6 Reverse Channel Send
8 Data Terminal Ready
15
17
25
OUTPUT SIGNALS
SIGNAL PIN
Transmitted Data
Request To Send
Chassis Ground
Signal Ground 7
2
4
11,14
20
1
Interfaces