issues using DMA with nrf9160

RE: issues using DMA with nrf9160

Håkon Alseth — Tue, 13 Aug 2019 11:52:11 GMT

Hi,

In order to enable DMA reception, with a given chunk size, you have to pass this to the uart_rx_enable function.

This means that all your data will be received in this chunk, as shown here:

https://github.com/zephyrproject-rtos/zephyr/blob/master/tests/drivers/uart/uart_async_api/src/test_uart_async.c#L56

What is the RXD DMA size you expect to receive?

How does your received data look compared to the sent data?

Kind regards,

Håkon

RE: issues using DMA with nrf9160

MosheSmartAmr — Tue, 13 Aug 2019 09:06:49 GMT

HI,

1. CTS/RTS is not used.

2. The buffers are statically allocated

3. I doubt that corrupt data is the case, we always memset all buffers to zero. also when not using DMA it works perfectly.

        memset(ubuf_image,0, sizeof(ubuf_image));
        uart_wifi = device_get_binding(DT_UART_1_NAME);
        if (!uart_wifi) {
                printk("error\r\n");
        }
        printk("ubuf_image=[0x%x]\n", ubuf_image);
#ifndef UART_DMA
        uart_irq_rx_enable(uart_wifi );
        printk("uart_irq_rx_enable() done\n");
        uart_irq_callback_set(uart_wifi , uart_cb);
#else
        uart_callback_set(uart_wifi, uart_callback_algo, uart_wifi);
#endif

Thanks!

RE: issues using DMA with nrf9160

Håkon Alseth — Mon, 12 Aug 2019 12:58:36 GMT

Hi,

Are you using CTS/RTS?

Are your buffers statically defined (ie: not malloc/calloc'ed)?

strlen() will parse output until it hits zero termination, could it be that the data has been corrupted, and zero chars is present in the buffer?

Could you show a code snippet on how you setup the UART?

Kind regards,

Håkon