SDK • Is there a way to know if the TX FIFO is empty before doing pull?

Hello,

For a connection to a specific device, I would like to connect the PICO to a synchronous HDLC serial link on Manchester encoding with bit stuffing and with inter-frame padding (flag repetition).

I can send the frame in Manchester with bit stuffing (thanks to the pico examples), but I don't see how to do the inter-frame padding.

Bit stuffing is done in the PIO because it is too difficult to implement it in C (byte boundary problem).

For the padding, I'm stuck because either the pull is blocking, so no padding is sent, or it is not blocking and the content of x is retrieved. But it is not possible to distinguish whether it is a flag (in which case the bit stuffing should not be done) or data to be transmitted (on which the bit stuffing should be done).

I was thinking about a possibility to know if the TX FIFO is empty before doing the pull?

Any idea?

Thanks!

Statistics: Posted by VincentAlex — Fri Nov 15, 2024 8:39 am

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