Hi guys.
In my current project i am trying to communicate with RS232 and RS485. Both should be present but one should be active. I am using MAX3160E transceiver, which allows me to switch between RS232 and RS485. Aim is to connect them to DB9 and control the transceiver to switch. But pin layout of DB9 confuses me. It seems like there is no standard. I wonder if it was correct to connect pins like this:
Also I couldn't fully understand the hardware flow control in RS232. According to MAX3160E datasheet one of the RS232 channels can be used for RTS CTS function and I am considering to use them. But is it proper to connect them to pin1 and pin4 which are actually DCD and DTR pins of standard DB9 pin layout? What is the difference between RTS/CTS flow control and DTR/DSR/DCD on the hardware side?
Thanks in advance.
edit: This is another configuration I wonder if it is proper:
In my current project i am trying to communicate with RS232 and RS485. Both should be present but one should be active. I am using MAX3160E transceiver, which allows me to switch between RS232 and RS485. Aim is to connect them to DB9 and control the transceiver to switch. But pin layout of DB9 confuses me. It seems like there is no standard. I wonder if it was correct to connect pins like this:
RS232 | RS485 | |
1 | CTS | R- |
2 | Rx | R+ |
3 | Tx | T+ |
4 | RTS | T- |
5 | GND | GND |
6 | ||
7 | ||
8 | ||
9 |
Also I couldn't fully understand the hardware flow control in RS232. According to MAX3160E datasheet one of the RS232 channels can be used for RTS CTS function and I am considering to use them. But is it proper to connect them to pin1 and pin4 which are actually DCD and DTR pins of standard DB9 pin layout? What is the difference between RTS/CTS flow control and DTR/DSR/DCD on the hardware side?
Thanks in advance.
edit: This is another configuration I wonder if it is proper:
RS232 | RS485 | |
1 | DCD | NC |
2 | Rx | R+ |
3 | Tx | T+ |
4 | DTR | NC |
5 | GND | GND |
6 | DSR | NC |
7 | RTS | T- |
8 | CTS | R- |
9 | RI |
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