Data received by Async UART on Teensy4 is looping and arriving repeatedly

[serhii-muchychka]

I'm trying to receive data via UART (without transmission yet). To do this, I made a double buffer like in the example

I turn on UART once at startup:

uart_rx_enable(m_serial, m_rxBuffers[0], sizeof(m_rxBuffers[0]), SYS_FOREVER_US);

The buffer request handler looks like this:

case UART_RX_BUF_REQUEST: {
    const auto newBufferIndex = self->m_rxBuffersIndex ^ std::uint8_t{ 1 };
    LOG_INF("RX buffer index: %d!", self->m_rxBuffersIndex);
    if (const auto error = uart_rx_buf_rsp(dev, self->m_rxBuffers[newBufferIndex],
                                           sizeof(m_rxBuffers[0]))) {
        LOG_ERR("Failed to replace buffer! index=%d, channel=%d: %s!", newBufferIndex,
                self->m_channelNo, strerror(-error));
    } else {
        self->m_rxBuffersIndex = newBufferIndex;
    }
    break;
 }

main function:

int main(void)
{
    const auto controller = std::make_unique<Controller>();

    while (1) {
        k_sleep(K_SECONDS(1));
    }
}

prj.conf

CONFIG_CPP=y
CONFIG_REQUIRES_FULL_LIBCPP=y
CONFIG_STD_CPP20=y

CONFIG_SERIAL=y
CONFIG_UART_ASYNC_API=y
CONFIG_LOG=y

After filling buffers of length 512, data is repeated, although UART_RX_RDY notifications come regularly. Zephyr 4.1.

Please tell me how to fix this 🙏