Libuarte splitting buffer data

RE: Libuarte splitting buffer data

SheepWool — Mon, 13 May 2024 09:05:00 GMT

Thanks Jerome. Some more digging here RE: LIBUARTE RX Buffer Full event

also found the similar solution. Thank god for these forums!

RE: Libuarte splitting buffer data

jerome.sc — Mon, 13 May 2024 08:34:49 GMT

Yea, it was such a pain when I had to deal with it. My way of dealing with it was to check if the libuarte buffer was full using the sub_rx_count, if so, check if I received my full packet by looking the start and end header. If the libuarte buffer was not full (so the data isn't split), check if I've received a full packet.

I don't really, remember all the details, but maybe to code snippet below will help (edited to remove sensitive information).

if (p_libuarte->p_ctrl_blk->sub_rx_count == 0) { // LIBUARTE buffer is full
        // Start filling app buffer.
        memcpy(app_buffer, p_evt->data.rxtx.p_data, app_length);
        // Index to add more data to.
        app_buffer_idx = app_length;

        // Check if full packet
        if ( I received a full packet process it) {
            // Full packet so go to processing
            NRF_LOG_INFO("Full packet so head to processing");
            // Reset the last index.
            app_buffer_idx = 0;
        } else { 
            // Not a full packet so wait until a full packet.
            return;
        }
    } else { // Buffer not full but ready to process data
        // Copy data to the work buffer starting from last index.
        memcpy(app_buffer + app_buffer_idx, p_evt->data.rxtx.p_data, app_length);

        app_length += app_buffer_idx; // Add on the extra length of partially full buffer.

        NRF_LOG_INFO("Printing full buffer:");
        NRF_LOG_HEXDUMP_INFO(app_buffer, app_length);

        // Reset the last index.
        app_buffer_idx = 0;
    }

RE: Libuarte splitting buffer data

SheepWool — Mon, 13 May 2024 08:18:08 GMT

This is also causing problems for me as the uart messages are being split and extra code has to be written to join them together. This is a right pain in the ars# for us because we need to act on specific message headers which come in asynchonously. It would be way easier if a ring buffer was used by Libuarte and a event was not generated just because it is at the end of its buffer.

RE: Libuarte splitting buffer data

jerome.sc — Thu, 20 Jul 2023 08:22:08 GMT

It's causing problems as I expect a full packet at a time, which gets processed later. I've fixed the issue, by putting the data into a buffer.

RE: Libuarte splitting buffer data

Jared — Wed, 19 Jul 2023 13:18:14 GMT

Hi,

[quote user=""]Is there any way to either modify the libraries to either only use one buffer, reset the rx index (and any other variables) after every transmission, or to use implement a buffer of some kind to store both parts of the data? I[/quote]

I don't think this is possible without redesigning the the module considerably.

[quote user=""], it will get the first part of the data (store into a buffer), and then in the next event, the second part will come. However, even with this implementation, it's causing problems.[/quote]

How is this not working, is it due to the latency of waiting for the second buffer to be filled?

regards

Jared