Is it good to use one UART interface on MCU, RX_UART for receiving data from RS422 receiver and TX_UART for transmitting the same data to the RS232 and RS422 transmitter? I am trying to use UART as "signal splitter", because I want to use my rs422 input signal and forward it to rs232 and other rs422.

EDIT: I can not ask another question, and don't know how to edit others to be allowed to ask again, but I would like to know this:

Why JTAG connectors use 20, 14 or 10 pins (standard), when only 7 is required (minimum, TDI, TDO, TMS, TCK, NTRS, GND, VDD)?


closed as unclear what you're asking by Olin Lathrop, PeterJ, Daniel Grillo, nidhin, Scott Seidman Feb 14 '16 at 14:40

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    \$\begingroup\$ That seems a little unclear. Your finished system will have what inputs and outputs? \$\endgroup\$ – Jasen Feb 9 '16 at 11:02
  • \$\begingroup\$ It would have RS422/485 input (one receiver), and outputs RS422 and RS232 (one driver for each). \$\endgroup\$ – Haris778 Feb 9 '16 at 11:34
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    \$\begingroup\$ Why do you need a UART at all? Just connect the receiver directly to the two drivers. \$\endgroup\$ – Dave Tweed Feb 9 '16 at 12:34
  • \$\begingroup\$ I could do that, but I also need received data to process in MCU. Maybe I should connect both drivers and MCU to receiver. Thank you. \$\endgroup\$ – Haris778 Feb 9 '16 at 12:45
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    \$\begingroup\$ Right, that's what I would do. One RS422 differential receiver connected to RS422 transmitter, RS232 transmitter, and the Rx input pin on your MCU. \$\endgroup\$ – Alexxx Feb 9 '16 at 14:59

no problem connecting a output to several inputs is normal, the limit is the fan out If you use MAX488 as a repeater of RS422 (connect DO to DI), you can connect a MAX232 Tx Input to the TTL side of MAX488 (DO + DI).


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