Atop Technology MB5416A2 User manual - Manual (Page 59)

Atop Modbus Gateway
MB54XX-X Series
User’s Manual V 1.1
56
DB9 to RS-232/RS-485/RS-422 connectors (MB5404D-X)
Table 5. 3
Pin#
RS-232
Full Duplex
RS-422/4-Wire RS-485
Full Duplex
2-Wire RS-485
Half Duplex
1 DCD N/A N/A
2 RXD TXD+ N/A (reserved)
3 TXD RXD+ DATA+
4 DTR N/A N/A
5 SG (Signal Ground) SG (Signal Ground) SG (Signal Ground)
6 DSR N/A N/A
7 RTS RXD- DATA-
8 CTS TXD- N/A (reserved)
9 RI N/A N/A