I would like to ask, when a port is set to RX0, is it necessary to set the input and output direction of this port?

一沙一世

I would like to ask, when a port is set to RX0, is it necessary to set the input and output direction of this port? [Copy link]

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I would like to ask, when a port is set to RX0, is it necessary to set the input and output direction of this port? Do I need to set its pull-up and pull-down?

wangerxian

If you multiplex into the RX mode of the serial port, you don't need to set the pull-up and pull-down.

一沙一世

wangerxian posted on 2023-8-11 13:33 If you reuse the RX mode of the serial port, you don’t need to set the pull-up and pull-down.

Thank you very much. Do I need to set the input and output direction?

chunyang

No more setup required.

wangerxian

Yishayishi published on 2023-8-11 15:09 Thank you very much. Do I need to set the input and output direction?

No, you have set them to multiplexed pins.

led2015

When a port is set as RX0 (receiving port), its input and output directions need to be set according to the specific application scenario. If the port is only used to receive data, it can be set to the input direction and does not need to be set to the output direction. If the port needs to be used to send data in some cases, it needs to be set to the output direction in these cases.

秦天qintian0303

For RX0, you only need to set the pin to multiplexing function. However, different microcontrollers have different libraries, so pay attention to the selection.

voidp

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hjl2832

The multiplexing function is a pure hardware circuit, which automatically switches the relevant internal hardware switches to the corresponding circuits. This is clearly explained in the chip manual. It can also be seen from the configuration of ST's CUBEMAX software that after you set the multiplexing function, the initialization code generally does not care about the input or output mode, nor does it care about pull-up and pull-down. It just sets the multiplexing mode to map to the corresponding hardware function.

emma2015

The multiplexing function is a pure hardware circuit, which automatically switches the relevant internal hardware switches to the corresponding circuits.