EasyDMA with UARTE and receiving variable sized messages

[corona]

Hi I'm porting an existing project from nrf51 to nrf52810 and trying to configure the UARTE EasyDMA to handle serial reception.

We have serial messages of variable length (between 2 and 18 bytes) being sent from a separate microcontroller to the nrf52, all with a null terminator on the end of each message.

Assuming I assign it a buffer large enough to receive the largest message possible, is there any way to trigger or detect an end of message from the null character received, or even from a timeout or something?

Is there any way to get an interrupt on each character received into the dma ram so I could check it for null and change the dma to point to a new buffer for the next message?

Thanks.

[MartinBL]

Hi,

Assuming I assign it a buffer large enough to receive the largest message possible, is there any way to trigger or detect an end of message from the null character received, or even from a timeout or something?

Unfortunately not.

 

Is there any way to get an interrupt on each character received into the dma ram so I could check it for null and change the dma to point to a new buffer for the next message?

As you can see in this documentation, you will get an RXDRDY event (that can trigger an interrupt) on every received byte. I suppose you can use this to check each received byte and change the pointer to the buffer accordingly, but then some of the point of EasyDMA is gone.