Problem sending 6 bytes to multiple services using sd_ble_gatts_hvx

[Renix]

I would like to confirm my understanding of Problem sending 6 bytes to multiple services using sd_ble_gatts_hvx

I use nrf52832 sdk13.0.0

BLE SPI is master. I dropped the SCK to 1 Mhz I send x18 bytes of data to slave, just to generate the SPI clock.

I receive all x18 bytes on MISO. I can view it with analyzer. I also see the correct data in m_rx_buf, in IAR watch window.

I have x3 BLE services. I update characteristic with this

our_termperature_characteristic_update(&m_our_service, &testchar[0]);

sr2_termperature_characteristic_update(&m_sr2_service, &testchar[6]);

sr3_termperature_characteristic_update(&m_sr3_service, &testchar[12]);

So the plan is to update service 1 with data[0] to [5] Service 2 with data[6] to [11], and service 3 with data[12] to [17]

I made all the changes in xxx_service.c

// OUR_JOB: Step 2.H, Set characteristic length in number of bytes

attr_char_value.max_len     = 6;
attr_char_value.init_len    = 6;
uint8_t value[6]            = {0x16, 0x15, 0x14, 0x13, 0x12, 0x11};

I changed characteristic to int8_t

// ALREADY_DONE_FOR_YOU: Function to be called when updating characteristic value

void our_termperature_characteristic_update(ble_os_t *p_our_service, int8_t *temperature_value)

If I pass the pointer to the first 6x bytes of the 18-byte array, all is fine. Charateristics of ALL three services are updated correctly.

our_termperature_characteristic_update(&m_our_service, &testchar[0]);

When I try to update a service with next six bytes, ALL three services fail.

So services update with &testchar[0]); but fail with &testchar[6]);

our_termperature_characteristic_update(&m_our_service, &testchar[6]);

So

// ALREADY_DONE_FOR_YOU: Function to be called when updating characteristic value

void our_termperature_characteristic_update(ble_os_t *p_our_service, int8_t *temperature_value)
{
    // OUR_JOB: Step 3.E, Update characteristic value
    if (p_our_service->conn_handle != BLE_CONN_HANDLE_INVALID)
    {
        uint16_t               len = 6;

Perhaps I do not understand the sending mechanism correctly, but at least the first 6-bytes of the array are sent correctly, without fail.

Passing the pointer to the next six bytes is where all fails.

Any help appreciated

[Renix]

Petter,

I believe I found the issue.

I was calling the characteristic updates from inside the 1sec timer routine.

So I think the SPI is free running, (in the main while loop) so it updates all the time.

During the time the 1sec timer interrupts, the SPI may have updated. So I moved the characteristic update calls to right after the nrf_drv_spi_transfer

FIXED!! A hack a day keeps the doctor away.

Regards

[Renix]

Petter,

I think the while (!spi_xfer_done) { __WFE(); } is causing problems. I removed the __WFE(); inside of the timer update, but still no go.

The only way I could get SPI to function correctly, was to leave it in the main loop, and place an if() around it, so set a flag inside the timer event, so the main() loop will the do the SPI transfer.

It works, so all I can say is unless the SPI was stopped, the asynchronous SPI reads with the Timer 1sec interrupt, does not work.

Thanks.