I´m running on NRF52840 with SDK version 15.2.0 and trying to use atfifo, and I have observed a bug when writing to the atfifo buffer twice and then reading from the atfifo buffer.
The phenomenon:
1. I´m writing 4 bytes to atfifo but first 3 bytes contains 0.
2. I´m writing many other bytes to atfifo.
3. I´m reading 4 bytes from atfifo but it contains data from both previous writes. The atfifo buffer seems to have been truncated.
I´m running following experimental code deriving from blinky example project on PCA10056:
#define DATA_BUFFER_SIZE 16384
NRF_ATFIFO_DEF(m_data_atfifo, uint8_t, DATA_BUFFER_SIZE);
/**
* @brief Function for application main entry.
*/
int main(void)
{
/* Configure board. */
bsp_board_init(BSP_INIT_LEDS);
NRF_ATFIFO_INIT(m_data_atfifo);
uint32_t data_size = 169;
uint8_t data[169];
data[0] = 0x01;
data[1] = 0x02;
data[2] = 0x03;
nrf_atfifo_alloc_put(m_data_atfifo, &data_size, sizeof(data_size), NULL);
nrf_atfifo_alloc_put(m_data_atfifo, data, data_size, NULL);
uint32_t get_size = 0;
nrf_atfifo_get_free(m_data_atfifo, &get_size, sizeof(get_size), NULL);
NRF_LOG_INFO("1. get_size: %x", get_size);
nrf_atfifo_clear(m_data_atfifo);
nrf_atfifo_alloc_put(m_data_atfifo, &data_size, sizeof(data_size), NULL);
nrf_atfifo_get_free(m_data_atfifo, &get_size, sizeof(get_size), NULL);
nrf_atfifo_alloc_put(m_data_atfifo, data, data_size, NULL);
NRF_LOG_INFO("2. get_size: %x", get_size);
/* Toggle LEDs. */
while (true)
{
for (int i = 0; i < LEDS_NUMBER; i++)
{
bsp_board_led_invert(i);
nrf_delay_ms(500);
}
}
}
My opinion is that get_size should contain same data 0x000000A9 in both printouts, but it´s not. In the first printout get_size contains 0x30201A9, while in second printout it contains 0x000000A9.
