Over time two labels have been used to denote this multifunction Serial Port.
Workstations such as the WS 4 LX and KW270 include two ports labeled RS422-A and RS422-B. Later workstations including the WS 6, WS 5A, PCWS 2015, and Base Station include a single RS422 port labeled ‘IDN’.
The IDN (COM4) and RS422-A/RS422-B (COM4 and COM5) ports are functionally equivalent, and default to RS422 mode in order to drive MICROS IDN printers. The figure below shows the pin-out of the RS422 configuration. The POS application can convert this port to a simple two- wire RS232 interface for driving serial peripherals.
Port Configured for driving RS422 IDN Devices – IDN (+)
The figure below shows the pin configuration of this port when driving IDN devices.
Figure 33-1 IDN or RS422-A/B Connectors Configured for IDN Printing
Port Configured for RS232 Devices
The figure below shows the multifunction modular port(s) configured as a basic RS232 Interface.
Figure 33-2 IDN or RS422-A/B Connectors Configured for RS232
Parent topic: Connectors