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How to set IOMUX of iMX6 dual UART?

Question asked by Yoshi Tanamura on Mar 3, 2016
Latest reply on Mar 6, 2016 by Yoshi Tanamura

Hello dear, 

We have an urgent question about IOMUX. 
Is it possible to set IOMUX with using combination of DCE mode and DTE mode,
when we construct UART communication under condition of below?
If possible, could you tell us target register which should be set by software, and its sequence?

1.To use UART with connecting an external UART device
2.To use TX_DATA signal, RX_DATA signal, CTS_B signal, and RTS_Bsignal
3."hardflow control" is valid.
4.To use both TX_DATA signal and RX_DATA signal as DCE mode like attached figure.
5.To use both CTS_B signal and RTS_B signal as DTE mode like attached figure.

Current status
As condition #5, we'd like to only use cross-connection of CTS_B signal and RTS_B signal
into IOMUX.  
At first, we set UART1 as DCE mode on linux enviroment.
After that, we change IOMUXC_UART1_UART_RTS_B_SELECTION_INPUT register value from "01"
(DCE mode) to "00"(DTE mode).
But we can't transfer data to external device.   

We'd like to transfer data to external device with using cross-connection above.
Could you tell us any resolution of that?
This is very urgent for us, so please give us any advices or comments as soon as possible. 


Thanks a lot.


Yoshi Tanamura