/*
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;
}
/*
Interrupt service routine called when the RDYN line goes low. Runs the SPI transfer.
*/
static void m_aci_isr(void)
{
hal_aci_data_t data_to_send;
hal_aci_data_t received_data;
// see guide from http://redbearlab.com/blend-low-power-settings/
#if defined(__AVR_ATmega32U4__)
PRR0 = 0x00; // Power Reduction Register: open timer
PRR1 = 0x00;
#endif
// Receive from queue
if (!aci_queue_dequeue_from_isr(&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 (!aci_queue_is_full_from_isr(&aci_rx_q) && !aci_queue_is_empty_from_isr(&aci_tx_q))
{
m_aci_reqn_enable();
}
// Check if we received data
if (received_data.buffer[0] > 0)
{
if (!aci_queue_enqueue_from_isr(&aci_rx_q, &received_data))
{
/* Receive Buffer full.
Should never happen.
Spin in a while loop.
*/
while(1);
}
// Disable ready line interrupt until we have room to store incoming messages
if (aci_queue_is_full_from_isr(&aci_rx_q))
{
detachInterrupt(a_pins_local_ptr->interrupt_number);
}
}
return;
}
/*
Interrupt service routine called when the RDYN line goes low. Runs the SPI transfer.
*/
static void m_aci_isr(void)
{
hal_aci_data_t data_to_send;
hal_aci_data_t received_data;
// Receive from queue
if (!aci_queue_dequeue_from_isr(&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 (!aci_queue_is_full_from_isr(&aci_rx_q) && !aci_queue_is_empty_from_isr(&aci_tx_q))
{
m_aci_reqn_enable();
}
// Check if we received data
if (received_data.buffer[0] > 0)
{
if (!aci_queue_enqueue_from_isr(&aci_rx_q, &received_data))
{
/* Receive Buffer full.
Should never happen.
Spin in a while loop.
*/
while(1);
}
// Disable ready line interrupt until we have room to store incoming messages
if (aci_queue_is_full_from_isr(&aci_rx_q))
{
detachInterrupt(a_pins_local_ptr->interrupt_number);
}
}
return;
}