I have a board that has a MAX232 and a MAX485. I want to switch between these peripherals' RX/TX signals which connected to Arduino. How would I achieve this? I am definetly not knowledgeable about this topic and need some help.
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\$\begingroup\$ Maybe using a multiplexer can help you please check here: forum.arduino.cc/t/multiplexing-serial-port-rx-tx/216905/5 \$\endgroup\$– anilbergDec 12, 2022 at 8:06
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\$\begingroup\$ @anilberg Yes, but I haven't a clue on how to use a multuplexer. \$\endgroup\$– Orlando Dlugoš ČehDec 12, 2022 at 8:36
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\$\begingroup\$ if you are only switching outputs, why bother? you could just drive both in parallel and leave both running. Unless you really do need to stop the output going to some destination under software control. \$\endgroup\$– danmcbDec 12, 2022 at 10:02
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\$\begingroup\$ electronics.stackexchange.com/help/someone-answers \$\endgroup\$– anilbergDec 27, 2022 at 8:35
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Okay for example you decided to use SN74CBT3257C bidirectional multiplexer. According to datasheet you can use 1B1 and 1B2 pins as input of MAX232_RX and MAX485_RX. When OE chip enable pin is low, you can select between MAX232_RX and MAX485_RX by changing logic level of S (when S = 1 then 1A = 1B2, otherwise 1A = 1B1).
With same way if you use 2B1 and 2B2 as an input of MAX232_TX and MAX485_TX.
