UART in half_duplex in K20(Single-wire Mode)

[reshmakalavoorc]

Hello,

I am trying to work with the UART in MK20DN512VLK10 processor in half duplex mode in RS485 type physical interface . 

When I try to work in Single-Wire UART mode (LOOPS =1 and RSRC =1), I am not able to receive the data even if the transmit direction is kept as Input (TXDIR  = Input).

Transmit works fine when the transmit direction is changed to Output(TXDIR  = Output).

Please let me know whether there is any other setting that needs to be done to receive the data.

[reshmakalavoorc]

Hi,

So if I am not wrong, both the data transmission and reception will happen through the TXD pin? 

Thanks

[fangli]

Hi,

For the single-wire UART mode, below steps should be done:

 Setting C1[LOOPS] =1 to disables the path from the unsynchronized receiver input signal to the receiver.

Setting C1[RSRC] =1 to enable the connection between receiver input to the output of the TXD pin.

Both the transmitter and receiver must be enabled (C2[TE] = 1 and C2[RE] = 1).