Technical data
Panel PC 2100 user's manual V1.17
203
2.3.5.8.3.2 COMD serial interface - Pinout
Serial interface COMD is referred to as IFx on the system unit.
Serial interface COMD - IFx
1)2)3)
RS422/RS485
Type
RS422/RS485, electrically isolated
UART
16550-compatible, 16-byte FIFO
Transfer rate
Max. 115 kbit/s
Bus length
Max. 1200 m
Pin
Assignment
1
RXD
2
RXD\
3
TXD
4
TXD\
5
COM GND
6
-
7
-
8
-
9
-
10
-
10-pin, male
1 3 5 7
2 4 6 8 10
9
Table 205: 5ACCIF01.FSS0-000 - Interface COMD
1)
The interfaces, etc. available on the device or module have been numbered as such for the purpose of clear differentiation. This numbering may deviate
from the numbering used by the respective operating system, however.
2)
This interface (if available) is enabled automatically in BIOS as COMD with default I/O address 2F8h and IRQ 10.
3)
This interface is referred to as IF8 in Automation Studio / Automation Runtime.
Operating COMD as an RS485 interface
The pins of the RS422 default interface (1, 2, 3 and 4) must be used for operation. Pins must be connected as
shown.
DATA
DATA
TXD
RXD
TXD
RXD
1
3
2
4
Figure 111: RS232/422/485 interface - COMD operation in RS485 mode
The RTS line must be switched by the driver for each transmission or reception; there is no automatic switch-
back mechanism.
The voltage drop resulting from long cable lengths can result in greater potential differences between the bus
stations, which can hinder communication. This can be improved by running the ground wire with the others.
