Ways to link a bi-directional GPIO with a direction (TX_EN) pin

[dav1]

Hi,

Assume you have a dma-controlled serial peripheral or fast gpio that requires an external buffer (for level shifting). Are there any ways in 'hardware' to get a "tandem pin" that controls the DIR pin of a buffer. 

mcu: LPC55S69JEV98

ps. I don't want to roll this in code, it has to be autonomous. 

[dav1]

hi alice,

can you please show with an example.

let's say one for I2C, one for SDIO, where both has an external buffer needing direction-control
i.e. how do we config the serial peripheral + DMA of the LPC to achieve a 2-way autonomous operation

thanks

[Alice_Yang]

Hello Dav,

Could you please descript your requirement more detail? thanks.

BR

Alice

[Alice_Yang]

Hello dav1,

No. 

If you don't want to use software , can try to use DMA to control the GPIO DIR.