void i2c_transfer_asynch(i2c_t *obj, const void *tx, size_t tx_length,
void *rx, size_t rx_length, uint32_t address,
uint32_t stop, uint32_t handler,
uint32_t event, DMAUsage hint)
{
(void)hint;
twi_info_t *twi_info = TWI_INFO(obj);
if (twi_info->active) {
return;
}
twi_info->active = true;
twi_info->events = 0;
twi_info->handler = (void (*)(void))handler;
twi_info->evt_mask = event;
twi_info->tx_length = tx_length;
twi_info->tx = tx;
twi_info->rx_length = rx_length;
twi_info->rx = rx;
twi_info->stop = stop;
NRF_TWI_Type *twi = m_twi_instances[TWI_IDX(obj)];
nrf_twi_event_clear(twi, NRF_TWI_EVENT_TXDSENT);
nrf_twi_event_clear(twi, NRF_TWI_EVENT_RXDREADY);
nrf_twi_event_clear(twi, NRF_TWI_EVENT_STOPPED);
nrf_twi_event_clear(twi, NRF_TWI_EVENT_SUSPENDED);
nrf_twi_event_clear(twi, NRF_TWI_EVENT_ERROR);
(void)nrf_twi_errorsrc_get_and_clear(twi);
nrf_twi_address_set(twi, twi_address(address));
nrf_twi_task_trigger(twi, NRF_TWI_TASK_RESUME);
// TX only, or TX + RX (after a repeated start).
if (tx_length > 0) {
nrf_twi_task_trigger(twi, NRF_TWI_TASK_STARTTX);
nrf_twi_txd_set(twi, *(twi_info->tx));
++(twi_info->tx);
// RX only.
} else if (rx_length > 0) {
start_asynch_rx(twi_info, twi);
// Both 'tx_length' and 'rx_length' are 0 - this case may be used
// to test if the slave is presentand ready for transfer (by just
// sending the address and checking if it is acknowledged).
} else {
nrf_twi_task_trigger(twi, NRF_TWI_TASK_STARTTX);
if (stop) {
nrf_twi_task_trigger(twi, NRF_TWI_TASK_STOP);
} else {
nrf_twi_task_trigger(twi, NRF_TWI_TASK_SUSPEND);
nrf_twi_int_enable(twi, NRF_TWI_INT_SUSPENDED_MASK);
}
twi_info->events |= I2C_EVENT_TRANSFER_COMPLETE;
}
nrf_twi_int_enable(twi, NRF_TWI_INT_TXDSENT_MASK |
NRF_TWI_INT_RXDREADY_MASK |
NRF_TWI_INT_STOPPED_MASK |
NRF_TWI_INT_ERROR_MASK);
}
static void start_twi_write(NRF_TWI_Type *twi, int address)
{
nrf_twi_event_clear(twi, NRF_TWI_EVENT_STOPPED);
nrf_twi_event_clear(twi, NRF_TWI_EVENT_TXDSENT);
nrf_twi_event_clear(twi, NRF_TWI_EVENT_ERROR);
(void)nrf_twi_errorsrc_get_and_clear(twi);
nrf_twi_shorts_set(twi, 0);
nrf_twi_address_set(twi, twi_address(address));
nrf_twi_task_trigger(twi, NRF_TWI_TASK_RESUME);
nrf_twi_task_trigger(twi, NRF_TWI_TASK_STARTTX);
}
static void start_twi_read(NRF_TWI_Type *twi, int address)
{
nrf_twi_event_clear(twi, NRF_TWI_EVENT_STOPPED);
nrf_twi_event_clear(twi, NRF_TWI_EVENT_RXDREADY);
nrf_twi_event_clear(twi, NRF_TWI_EVENT_ERROR);
(void)nrf_twi_errorsrc_get_and_clear(twi);
nrf_twi_shorts_set(twi, NRF_TWI_SHORT_BB_SUSPEND_MASK);
nrf_twi_address_set(twi, twi_address(address));
nrf_twi_task_trigger(twi, NRF_TWI_TASK_RESUME);
nrf_twi_task_trigger(twi, NRF_TWI_TASK_STARTRX);
}
int i2c_write(i2c_t *obj, int address, const char *data, int length, int stop)
{
twi_info_t *twi_info = TWI_INFO(obj);
nrf_drv_twi_t const *twi = &m_twi_instances[TWI_IDX(obj)];
twi_info->transfer_finished = false;
ret_code_t ret_code = nrf_drv_twi_tx(twi, twi_address(address),
(uint8_t const *)data, length, (stop == 0));
if (ret_code != NRF_SUCCESS) {
return 0;
}
while (!twi_info->transfer_finished) {}
return nrf_drv_twi_data_count_get(twi);
}
void i2c_transfer_asynch(i2c_t *obj, const void *tx, size_t tx_length,
void *rx, size_t rx_length, uint32_t address,
uint32_t stop, uint32_t handler,
uint32_t event, DMAUsage hint)
{
(void)stop;
(void)hint;
if (i2c_active(obj)) {
return;
}
if ((tx_length == 0) && (rx_length == 0)) {
return;
}
twi_info_t *twi_info = TWI_INFO(obj);
twi_info->events = 0;
twi_info->handler = (void (*)(void))handler;
twi_info->event_mask = event;
uint8_t twi_addr = twi_address(address);
nrf_drv_twi_t const *twi = &m_twi_instances[TWI_IDX(obj)];
if ((tx_length > 0) && (rx_length == 0)) {
nrf_drv_twi_xfer_desc_t const xfer =
NRF_DRV_TWI_XFER_DESC_TX(twi_addr, (uint8_t *)tx, tx_length);
nrf_drv_twi_xfer(twi, &xfer,
stop ? 0 : NRF_DRV_TWI_FLAG_TX_NO_STOP);
}
else if ((tx_length == 0) && (rx_length > 0)) {
nrf_drv_twi_xfer_desc_t const xfer =
NRF_DRV_TWI_XFER_DESC_RX(twi_addr, rx, rx_length);
nrf_drv_twi_xfer(twi, &xfer, 0);
}
else if ((tx_length > 0) && (rx_length > 0)) {
nrf_drv_twi_xfer_desc_t const xfer =
NRF_DRV_TWI_XFER_DESC_TXRX(twi_addr,
(uint8_t *)tx, tx_length, rx, rx_length);
nrf_drv_twi_xfer(twi, &xfer, 0);
}
}
