Seco CCHPC-C78-C User Manual page 55

5
7 COM0_RTS#
8 COM1_RTS#
9 COM0_CTS#
10 COM1_CTS#
JP18 position COM #0 Working Mode
1-2 RS-422
2-3 RS-232
NO jumper RS-485
When RTS# signal is driven low, then the RS-485 port is in receiving mode, when RTS# signal is driven high then the RS-485 port is in transmitting mode.
The UART Port #1, however, is shared (at TTL level) with the BMC connector CN58 (see par. 3.3.19).
For this reason, a dedicated 3-way jumpers allow the redirection of the above mentioned UART port, according to the table below.
JP37 position UART port #1 connected to
1-2 COM #1 internal header CN26
2-3 BMC Connector CN58
CCHPC-C78-C
CCHPC-C78-C - Rev. First Edition: 1.0 - Last Edition: 1.0 - Author: S.O. - Reviewed by E.S. Copyright © 2023 SECO S.p.A.
GND
COM0_Tx+ COM0_Rx+/COM0_Tx+
COM1_Tx+ COM1_Rx+/COM1_Tx+
COM0_Rx-
COM1_Rx-
JP19 position
These two COM ports are made externally accessible through two
multistandard transceivers, which allow using them in RS-232, RS-
422 or RS-485 mode. Related outputs are available on an internal 9-pin standard
male pin header, p 2.54 mm, 5+4 pin, h= 6mm, type NELTRON p/n 2213S-
10G-E06 or equivalent.
Selection of working mode is made using jumpers JP18 and JP19,
which are standard pin headers, P2.54mm, 1x3 pin.
COM #1 Working Mode
1-2 RS-422
2-3 RS-232
NO jumper RS-485
Please be aware that for proper
RS-485 working, the RTS#
signals must be used as a
handshaking signal, i.e. it is used
to control the data flow direction.
55