/*
Checks the RDYN line and runs the SPI transfer if required.
*/
static void m_aci_event_check(void)
{
hal_aci_data_t data_to_send;
hal_aci_data_t received_data;
// No room to store incoming messages
if (aci_queue_is_full(&aci_rx_q))
{
return;
}
// If the ready line is disabled and we have pending messages outgoing we enable the request line
if (HIGH == mraa_gpio_read (a_pins_local_ptr->m_rdy_ctx))
// if (HIGH == digitalRead(a_pins_local_ptr->rdyn_pin))
{
if (!aci_queue_is_empty(&aci_tx_q))
{
m_aci_reqn_enable();
}
return;
}
// Receive from queue
if (!aci_queue_dequeue(&aci_tx_q, &data_to_send))
{
/* queue was empty, nothing to send */
data_to_send.status_byte = 0;
data_to_send.buffer[0] = 0;
}
// Receive and/or transmit data
m_aci_spi_transfer(&data_to_send, &received_data);
/* If there are messages to transmit, and we can store the reply, we request a new transfer */
if (!aci_queue_is_full(&aci_rx_q) && !aci_queue_is_empty(&aci_tx_q))
{
m_aci_reqn_enable();
}
// Check if we received data
if (received_data.buffer[0] > 0)
{
if (!aci_queue_enqueue(&aci_rx_q, &received_data))
{
/* Receive Buffer full.
Should never happen.
Spin in a while loop.
*/
while(1);
}
}
return;
}
bool hal_aci_tl_event_get(hal_aci_data_t *p_aci_data)
{
bool was_full;
#ifdef HAL_ACI_TL_INTERRUPT
if (!a_pins_local_ptr->interface_is_interrupt && !aci_queue_is_full(&aci_rx_q))
#else
if (!aci_queue_is_full(&aci_rx_q))
#endif
{
m_aci_event_check();
}
was_full = aci_queue_is_full(&aci_rx_q);
if (aci_queue_dequeue(&aci_rx_q, p_aci_data))
{
#ifdef HAL_ACI_TL_DEBUG
if (aci_debug_print)
{
Serial.print(" E");
m_aci_data_print(p_aci_data);
}
#endif
#ifdef HAL_ACI_TL_INTERRUPT
if (was_full && a_pins_local_ptr->interface_is_interrupt)
{
/* Enable RDY line interrupt again */
attachInterrupt(a_pins_local_ptr->interrupt_number, m_aci_isr, LOW);
#if defined(SPI_HAS_TRANSACTION) && defined(__SAMD21G18A__)
SPI.usingInterrupt(a_pins->interrupt_number);
#endif
}
#endif
/* Attempt to pull REQN LOW since we've made room for new messages */
if (!aci_queue_is_full(&aci_rx_q) && !aci_queue_is_empty(&aci_tx_q))
{
m_aci_reqn_enable();
}
return true;
}
return false;
}
bool hal_aci_tl_event_get(hal_aci_data_t *p_aci_data)
{
bool was_full;
if (!a_pins_local_ptr->interface_is_interrupt && !aci_queue_is_full(&aci_rx_q))
{
m_aci_event_check();
}
was_full = aci_queue_is_full(&aci_rx_q);
if (aci_queue_dequeue(&aci_rx_q, p_aci_data))
{
if (aci_debug_print)
{
Serial.print(" E");
m_aci_data_print(p_aci_data);
}
if (was_full && a_pins_local_ptr->interface_is_interrupt)
{
/* Enable RDY line interrupt again */
attachInterrupt(a_pins_local_ptr->interrupt_number, m_aci_isr, LOW);
}
/* Attempt to pull REQN LOW since we've made room for new messages */
if (!aci_queue_is_full(&aci_rx_q) && !aci_queue_is_empty(&aci_tx_q))
{
m_aci_reqn_enable();
}
return true;
}
return false;
}
