/*
* \brief Starts ED Scan
*
* This function starts an ED Scan for the scan duration specified by the
* MAC layer.
*
* \param scan_duration Specifies the ED scan duration in symbols
*
* \return MAC_SUCCESS - ED scan duration timer started successfully
* TAL_BUSY - TAL is busy servicing the previous request from MAC
* TAL_TRX_ASLEEP - Transceiver is currently sleeping
* FAILURE otherwise
*/
retval_t tal_ed_start(uint8_t scan_duration)
{
/*
* Check if the TAL is in idle state. Only in idle state it can
* accept and ED request from the MAC.
*/
if (TAL_IDLE != tal_state)
{
if (tal_trx_status == TRX_SLEEP)
{
return TAL_TRX_ASLEEP;
}
else
{
Assert("TAL is TAL_BUSY" == 0);
return TAL_BUSY;
}
}
/*
* Disable the transceiver interrupts to prevent frame reception
* while performing ED scan.
*/
pal_trx_irq_dis(); /* Disable transceiver main interrupt. */
set_trx_state(CMD_FORCE_PLL_ON);
pal_trx_reg_read(RG_IRQ_STATUS); /* Clear existing interrupts */
pal_trx_bit_write(SR_RX_PDT_DIS, RX_DISABLE);
pal_trx_irq_init((FUNC_PTR)trx_ed_irq_handler_cb);
pal_trx_bit_write(SR_IRQ_MASK, TRX_IRQ_CCA_ED_READY); /* enable interrupt */
pal_trx_irq_en(); /* Enable main transceiver interrupt. */
/* Make sure that receiver is switched on. */
if (set_trx_state(CMD_RX_ON) != RX_ON)
{
/* Restore previous configuration */
pal_trx_bit_write(SR_RX_PDT_DIS, RX_ENABLE);
pal_trx_irq_init((FUNC_PTR)trx_irq_handler_cb);
pal_trx_reg_write(RG_IRQ_MASK, TRX_IRQ_DEFAULT); /* enable TRX_END interrupt */
pal_trx_irq_en(); /* Enable main transceiver interrupt. */
return FAILURE;
}
// write dummy value to start measurement
pal_trx_reg_write(RG_PHY_ED_LEVEL, 0xFF);
/* Perform ED in TAL_ED_RUNNING state. */
tal_state = TAL_ED_RUNNING;
max_ed_level = 0; // reset max value
sampler_counter = CALCULATE_SYMBOL_TIME_SCAN_DURATION(scan_duration) / ED_SAMPLE_DURATION_SYM;
return MAC_SUCCESS;
}
/*
* \brief Scan done
*
* This function updates the max_ed_level and invokes the callback function
* tal_ed_end_cb().
*
* \param parameter unused callback parameter
*/
void ed_scan_done(void)
{
pal_trx_bit_write(SR_RX_PDT_DIS, RX_ENABLE);
pal_trx_irq_init((FUNC_PTR)trx_irq_handler_cb);
pal_trx_reg_write(RG_IRQ_MASK, TRX_IRQ_DEFAULT); /* enable TRX_END interrupt */
pal_trx_irq_en(); /* Enable transceiver main interrupt. */
tal_state = TAL_IDLE; // ed scan is done
set_trx_state(CMD_RX_AACK_ON);
#ifndef TRX_REG_RAW_VALUE
/*
* Scale ED result.
* Clip values to 0xFF if > -35dBm
*/
if (max_ed_level > CLIP_VALUE_REG)
{
max_ed_level = 0xFF;
}
else
{
max_ed_level = (uint8_t)(((uint16_t)max_ed_level * 0xFF) / CLIP_VALUE_REG);
}
#endif
tal_ed_end_cb(max_ed_level);
}
/**
* \brief Sends the frame at the next backoff boundary
*/
static void send_frame_at_next_backoff_boundary(void)
{
uint8_t ack_is_requested;
uint32_t now_time_us;
/*
* Locate the next backoff boundary for the frame transmissiom;
* this backoff boundary is the starttime for the frame fransmission.
* Use a blocking approach, since next backoff boundary should be close.
*/
do {
pal_get_current_time(&now_time_us);
} while (pal_add_time_us(now_time_us, PRE_TX_DURATION_US) <
cca_starttime_us);
/* re-programm the interrupt handler */
pal_trx_irq_init((FUNC_PTR)ack_reception_handler_cb);
pal_trx_irq_en();
/* debug pin to switch on: define ENABLE_DEBUG_PINS, pal_config.h */
PIN_TX_START();
/* Check if an acknowledgement is requested for this frame. */
ack_is_requested = *(tal_frame_to_tx + 1) & FCF_ACK_REQUEST;
if (ack_is_requested > 0) {
tal_csma_state = FRAME_SENDING_WITH_ACK;
} else {
tal_csma_state = FRAME_SENDING_NO_ACK;
}
/* download and send frame, no CSMA and no frame_retry */
send_frame(NO_CSMA_NO_IFS, false);
}
/**
* \brief Start CCA.
*
* \param parameter Unused callback parameter
*/
static void cca_start(void *parameter)
{
tal_state = TAL_CCA;
if (set_trx_state(CMD_PLL_ON) == PLL_ON) {
tal_trx_status_t trx_state;
/* No interest in receiving frames while doing CCA */
pal_trx_bit_write(SR_RX_PDT_DIS, RX_DISABLE); /* disable frame
* reception
* indication */
do {
trx_state = set_trx_state(CMD_RX_ON);
} while (trx_state != RX_ON);
/* Setup interrupt handling for CCA IRQ */
pal_trx_irq_init((FUNC_PTR)cca_done_irq_handler);
pal_trx_reg_write(RG_IRQ_MASK, TRX_IRQ_CCA_ED_READY); /* enable
*CCA
*interrupt
**/
/* Start CCA */
pal_trx_bit_write(SR_CCA_REQUEST, CCA_START);
} else {
/* Channel is busy, i.e. device is receiving */
tal_state = TAL_CSMA_CONTINUE;
}
/* Keep compiler happy. */
parameter = parameter;
}
/**
* \brief Finalizes the CSMA procedure
*
* \param status Result of the slotted transmission
*/
static void tx_done(retval_t status)
{
#if (_DEBUG_ > 0)
switch (tal_state) {
case TAL_SLOTTED_CSMA:
case TAL_TX_BASIC:
break;
#if ((MAC_START_REQUEST_CONFIRM == 1) && (defined BEACON_SUPPORT))
case TAL_TX_BEACON:
Assert("unexpected tal_state TAL_TX_BEACON" == 0);
return;
/* break; */
#endif /* ((MAC_START_REQUEST_CONFIRM == 1) && (defined BEACON_SUPPORT)) */
default:
Assert("unexpected tal_state" == 0);
break;
}
#endif
#if (_DEBUG_ > 0)
if (pal_is_timer_running(TAL_CSMA_BEACON_LOSS_TIMER)) {
Assert("beacon lost timer is still running" == 0);
}
#endif
tal_state = TAL_IDLE;
tal_csma_state = CSMA_IDLE;
/*
* Restore the interrupt handler.
* Install a handler for the transceiver interrupt.
*/
pal_trx_irq_init((FUNC_PTR)trx_irq_handler_cb);
pal_trx_reg_read(RG_IRQ_STATUS);
/* Check if a receive buffer is available. */
if (NULL != tal_rx_buffer) {
pal_trx_reg_write(RG_TRX_STATE, CMD_RX_AACK_ON);
} else {
tal_rx_on_required = true;
}
pal_trx_irq_en();
/* debug pin to switch on: define ENABLE_DEBUG_PINS, pal_config.h */
PIN_CSMA_END();
tal_tx_frame_done_cb(status, mac_frame_ptr);
}
/*
* \brief handling of CCA result.
*/
void cca_done_handling(void)
{
set_trx_state(CMD_PLL_ON); /* leave RX_ON */
/* Restore IRQ handling */
pal_trx_irq_init((FUNC_PTR)trx_irq_handler_cb);
pal_trx_reg_write(RG_IRQ_MASK, TRX_IRQ_DEFAULT);
pal_trx_bit_write(SR_RX_PDT_DIS, RX_ENABLE); /* Enable frame reception.
**/
/* Check if channel was idle or busy */
if (pal_trx_bit_read(SR_CCA_STATUS) == CCA_STATUS_CHANNEL_IS_IDLE) {
tx_frame();
} else {
tal_state = TAL_CSMA_CONTINUE;
}
}
/**
* @brief Sets transceiver state
*
* @param trx_cmd needs to be one of the trx commands
*
* @return current trx state
*/
tal_trx_status_t set_trx_state(trx_cmd_t trx_cmd)
{
if (tal_trx_status == TRX_SLEEP)
{
/*
* Since the wake-up procedure relies on the Awake IRQ and
* the global interrupts may be disabled at this point of time,
* we need to make sure that the global interrupts are enabled
* during wake-up procedure.
* Once the TRX is awake, the original state of the global interrupts
* will be restored.
*/
/* Reset wake-up interrupt flag. */
tal_awake_end_flag = false;
/* Set callback function for the awake interrupt. */
pal_trx_irq_init(trx_irq_awake_handler_cb);
/* The pending transceiver interrupts on the microcontroller are cleared. */
pal_trx_irq_flag_clr();
pal_trx_irq_en(); /* Enable transceiver main interrupt. */
/* Save current state of global interrupts. */
ENTER_CRITICAL_REGION();
/* Force enabling of global interrupts. */
ENABLE_GLOBAL_IRQ();
/* Leave trx sleep mode. */
PAL_SLP_TR_LOW();
/* Poll wake-up interrupt flag until set within ISR. */
while (!tal_awake_end_flag);
/* Restore original state of global interrupts. */
LEAVE_CRITICAL_REGION();
/* Clear existing interrupts */
pal_trx_reg_read(RG_IRQ_STATUS);
/* Re-install default IRQ handler for main interrupt. */
pal_trx_irq_init(trx_irq_handler_cb);
/* Re-enable TRX_END interrupt */
pal_trx_reg_write(RG_IRQ_MASK, TRX_IRQ_DEFAULT);
#if (ANTENNA_DIVERSITY == 1)
/* Enable antenna diversity. */
pal_trx_bit_write(SR_ANT_EXT_SW_EN, ANT_EXT_SW_ENABLE);
#endif
#ifdef EXT_RF_FRONT_END_CTRL
/* Enable RF front end control */
pal_trx_bit_write(SR_PA_EXT_EN, 1);
#endif
tal_trx_status = TRX_OFF;
if ((trx_cmd == CMD_TRX_OFF) || (trx_cmd == CMD_FORCE_TRX_OFF))
{
return TRX_OFF;
}
}
#ifdef ENABLE_DEEP_SLEEP
else if (tal_trx_status == TRX_DEEP_SLEEP)
{
/* Leave trx sleep mode. */
PAL_SLP_TR_LOW();
/* Check if trx has left deep sleep. */
tal_trx_status_t trx_state;
do
{
trx_state = (tal_trx_status_t)pal_trx_reg_read(RG_TRX_STATUS);
}
while (trx_state != TRX_OFF);
tal_trx_status = TRX_OFF;
/* Using deep sleep, the transceiver's registers need to be restored. */
trx_config();
/*
* Write all PIB values to the transceiver
* that are needed by the transceiver itself.
*/
write_all_tal_pib_to_trx(); /* implementation can be found in 'tal_pib.c' */
if ((trx_cmd == CMD_TRX_OFF) || (trx_cmd == CMD_FORCE_TRX_OFF))
{
return TRX_OFF;
}
}
#endif
switch (trx_cmd) /* requested state */
{
case CMD_SLEEP:
#ifdef ENABLE_DEEP_SLEEP
/* Fall through. */
case CMD_DEEP_SLEEP:
#endif
pal_trx_reg_write(RG_TRX_STATE, CMD_FORCE_TRX_OFF);
#if (ANTENNA_DIVERSITY == 1)
/*
* Disable antenna diversity: to reduce the power consumption or
* avoid leakage current of an external RF switch during SLEEP.
*/
pal_trx_bit_write(SR_ANT_EXT_SW_EN, ANT_EXT_SW_DISABLE);
#endif
#ifdef EXT_RF_FRONT_END_CTRL
/* Disable RF front end control */
pal_trx_bit_write(SR_PA_EXT_EN, 0);
#endif
/* Clear existing interrupts */
pal_trx_reg_read(RG_IRQ_STATUS);
/*
* Enable Awake_end interrupt.
* This is used for save wake-up from sleep later.
*/
pal_trx_bit_write(SR_IRQ_MASK, TRX_IRQ_4_CCA_ED_DONE);
#ifdef ENABLE_DEEP_SLEEP
if (trx_cmd == CMD_DEEP_SLEEP)
{
pal_trx_reg_write(RG_TRX_STATE, CMD_PREP_DEEP_SLEEP);
tal_trx_status = TRX_DEEP_SLEEP;
}
else
{
/*
* Enable Awake_end interrupt.
* This is used for save wake-up from sleep later.
*/
pal_trx_bit_write(SR_IRQ_MASK, TRX_IRQ_4_CCA_ED_DONE);
tal_trx_status = TRX_SLEEP;
}
#else
/*
* Enable Awake_end interrupt.
* This is used for save wake-up from sleep later.
*/
pal_trx_bit_write(SR_IRQ_MASK, TRX_IRQ_4_CCA_ED_DONE);
tal_trx_status = TRX_SLEEP;
#endif
PAL_WAIT_1_US();
PAL_SLP_TR_HIGH();
pal_timer_delay(TRX_OFF_TO_SLEEP_TIME_CLKM_CYCLES);
/* Transceiver register cannot be read during TRX_SLEEP or DEEP_SLEEP. */
return tal_trx_status;
case CMD_TRX_OFF:
switch (tal_trx_status)
{
case TRX_OFF:
break;
default:
pal_trx_reg_write(RG_TRX_STATE, CMD_TRX_OFF);
PAL_WAIT_1_US();
break;
}
break;
case CMD_FORCE_TRX_OFF:
switch (tal_trx_status)
{
case TRX_OFF:
break;
default:
pal_trx_reg_write(RG_TRX_STATE, CMD_FORCE_TRX_OFF);
PAL_WAIT_1_US();
break;
}
break;
case CMD_PLL_ON:
switch (tal_trx_status)
{
case PLL_ON:
break;
case TRX_OFF:
switch_pll_on();
break;
case RX_ON:
case RX_AACK_ON:
case TX_ARET_ON:
pal_trx_reg_write(RG_TRX_STATE, CMD_PLL_ON);
PAL_WAIT_1_US();
break;
case BUSY_RX:
case BUSY_TX:
case BUSY_RX_AACK:
case BUSY_TX_ARET:
/* do nothing if trx is busy */
break;
default:
ASSERT("state transition not handled" == 0);
break;
}
break;
case CMD_FORCE_PLL_ON:
switch (tal_trx_status)
{
case TRX_OFF:
switch_pll_on();
break;
case PLL_ON:
break;
default:
pal_trx_reg_write(RG_TRX_STATE, CMD_FORCE_PLL_ON);
break;
}
break;
case CMD_RX_ON:
switch (tal_trx_status)
{
case RX_ON:
break;
case PLL_ON:
case RX_AACK_ON:
case TX_ARET_ON:
pal_trx_reg_write(RG_TRX_STATE, CMD_RX_ON);
PAL_WAIT_1_US();
break;
case TRX_OFF:
switch_pll_on();
pal_trx_reg_write(RG_TRX_STATE, CMD_RX_ON);
PAL_WAIT_1_US();
break;
case BUSY_RX:
case BUSY_TX:
case BUSY_RX_AACK:
case BUSY_TX_ARET:
/* do nothing if trx is busy */
break;
default:
ASSERT("state transition not handled" == 0);
break;
}
break;
case CMD_RX_AACK_ON:
switch (tal_trx_status)
{
case RX_AACK_ON:
break;
case TX_ARET_ON:
case PLL_ON:
case RX_ON:
pal_trx_reg_write(RG_TRX_STATE, CMD_RX_AACK_ON);
PAL_WAIT_1_US();
break;
case TRX_OFF:
switch_pll_on(); // state change from TRX_OFF to RX_AACK_ON can be done directly, too
pal_trx_reg_write(RG_TRX_STATE, CMD_RX_AACK_ON);
PAL_WAIT_1_US();
break;
case BUSY_RX:
case BUSY_TX:
case BUSY_RX_AACK:
case BUSY_TX_ARET:
/* do nothing if trx is busy */
break;
default:
ASSERT("state transition not handled" == 0);
break;
}
break;
case CMD_TX_ARET_ON:
switch (tal_trx_status)
{
case TX_ARET_ON:
break;
case PLL_ON:
case RX_ON:
case RX_AACK_ON:
pal_trx_reg_write(RG_TRX_STATE, CMD_TX_ARET_ON);
PAL_WAIT_1_US();
break;
case TRX_OFF:
switch_pll_on(); // state change from TRX_OFF to TX_ARET_ON can be done directly, too
pal_trx_reg_write(RG_TRX_STATE, CMD_TX_ARET_ON);
PAL_WAIT_1_US();
break;
case BUSY_RX:
case BUSY_TX:
case BUSY_RX_AACK:
case BUSY_TX_ARET:
/* do nothing if trx is busy */
break;
default:
ASSERT("state transition not handled" == 0);
break;
}
break;
default:
/* CMD_NOP, CMD_TX_START */
ASSERT("trx command not handled" == 0);
break;
}
do
{
tal_trx_status = (tal_trx_status_t)pal_trx_bit_read(SR_TRX_STATUS);
}
while (tal_trx_status == STATE_TRANSITION_IN_PROGRESS);
return tal_trx_status;
} /* set_trx_state() */
/**
* @brief Initializes the TAL
*
* This function is called to initialize the TAL. The transceiver is
* initialized, the TAL PIBs are set to their default values, and the TAL state
* machine is set to TAL_IDLE state.
*
* @return MAC_SUCCESS if the transceiver state is changed to TRX_OFF and the
* current device part number and version number are correct;
* FAILURE otherwise
*/
retval_t tal_init(void)
{
/* Init the PAL and by this means also the transceiver interface */
#ifdef ENABLE_RP
/*
* The ranging processor (RP) only performs a minimalistic
* initialization here.
*/
pal_basic_init();
#else /* !ENABLE_RP */
if (pal_init() != MAC_SUCCESS)
{
return FAILURE;
}
if (trx_init() != MAC_SUCCESS)
{
return FAILURE;
}
#if (EXTERN_EEPROM_AVAILABLE == 1)
pal_ps_get(EXTERN_EEPROM, EE_IEEE_ADDR, 8, &tal_pib.IeeeAddress);
#else
#if (USER_SIGN_AVAILABLE == 1)
pal_ps_get(USER_SIGNATURE, USER_SIGNATURES_START + 2, 8, &tal_pib.IeeeAddress);
//http://www.atmel.com/Images/Atmel-42172-Wireless-ZigBit-ATZB-X0-256-3-0-C_Datasheet.pdf
#else
pal_ps_get(INTERN_EEPROM, EE_IEEE_ADDR, 8, &tal_pib.IeeeAddress);
#endif
#endif
/*
* Do the reset stuff.
* Set the default PIBs.
* Generate random seed.
*/
if (internal_tal_reset(true) != MAC_SUCCESS)
{
return FAILURE;
}
#ifndef DISABLE_IEEE_ADDR_CHECK
/* Check if a valid IEEE address is available. */
/*
* This while loop is on purpose, since just in the
* rare case that such an address is randomly
* generated again, we must repeat this.
*/
while ((tal_pib.IeeeAddress == 0x0000000000000000) ||
(tal_pib.IeeeAddress == 0xFFFFFFFFFFFFFFFF))
{
/*
* In case no valid IEEE address is available, a random
* IEEE address will be generated to be able to run the
* applications for demonstration purposes.
* In production code this can be omitted.
*/
/*
* The proper seed for function rand() has already been generated
* in function tal_generate_rand_seed().
*/
uint8_t *ptr_pib = (uint8_t *)&tal_pib.IeeeAddress;
for (uint8_t i = 0; i < 8; i++)
{
*ptr_pib++ = (uint8_t)rand();
/*
* Note:
* Even if casting the 16 bit rand value back to 8 bit,
* and running the loop 8 timers (instead of only 4 times)
* may look cumbersome, it turns out that the code gets
* smaller using 8-bit here.
* And timing is not an issue at this place...
*/
}
}
#endif /* #ifndef DISABLE_IEEE_ADDR_CHECK */
#endif /* ENABLE_RP */
/*
* Configure interrupt handling.
* Install a handler for the transceiver interrupt.
*/
pal_trx_irq_init(trx_irq_handler_cb);
#ifndef ENABLE_RP
pal_trx_irq_en(); /* Enable transceiver main interrupt. */
#endif
#if ((defined BEACON_SUPPORT) || (defined ENABLE_TSTAMP)) && (DISABLE_TSTAMP_IRQ == 0)
/* Configure time stamp interrupt. */
pal_trx_irq_init_tstamp(trx_irq_timestamp_handler_cb);
#ifndef ENABLE_RP
pal_trx_irq_en_tstamp(); /* Enable timestamp interrupt. */
#endif
#endif
/* Initialize the buffer management module and get a buffer to store received frames. */
bmm_buffer_init();
tal_rx_buffer = bmm_buffer_alloc(LARGE_BUFFER_SIZE);
#if DEBUG > 0
if (tal_rx_buffer == NULL)
{
return FAILURE;
}
#endif
/* Init incoming frame queue */
#ifdef ENABLE_QUEUE_CAPACITY
qmm_queue_init(&tal_incoming_frame_queue, TAL_INCOMING_FRAME_QUEUE_CAPACITY);
#else
qmm_queue_init(&tal_incoming_frame_queue);
#endif /* ENABLE_QUEUE_CAPACITY */
#ifdef ENABLE_TFA
tfa_init();
#endif
return MAC_SUCCESS;
} /* tal_init() */
/**
* @brief Resets TAL state machine and sets the default PIB values if requested
*
* @param set_default_pib Defines whether PIB values need to be set
* to its default values
*
* @return MAC_SUCCESS if the transceiver state is changed to TRX_OFF
* FAILURE otherwise
*/
retval_t tal_reset(bool set_default_pib)
{
/*
* Do the reset stuff.
* Set the default PIBs depending on the given parameter set_default_pib.
* Do NOT generate random seed again.
*/
if (internal_tal_reset(set_default_pib) != MAC_SUCCESS)
{
return FAILURE;
}
#if (NUMBER_OF_TAL_TIMERS > 0)
/* Clear all running TAL timers. */
{
uint8_t timer_id;
ENTER_CRITICAL_REGION();
for (timer_id = TAL_FIRST_TIMER_ID; timer_id <= TAL_LAST_TIMER_ID;
timer_id++)
{
pal_timer_stop(timer_id);
}
LEAVE_CRITICAL_REGION();
}
#endif
/* Clear TAL Incoming Frame queue and free used buffers. */
while (tal_incoming_frame_queue.size > 0)
{
buffer_t *frame = qmm_queue_remove(&tal_incoming_frame_queue, NULL);
if (NULL != frame)
{
bmm_buffer_free(frame);
}
}
#ifdef ENABLE_TFA
tfa_reset(set_default_pib);
#endif
/*
* Configure interrupt handling.
* Install a handler for the transceiver interrupt.
*/
pal_trx_irq_init(trx_irq_handler_cb);
/* The pending transceiver interrupts on the microcontroller are cleared. */
pal_trx_irq_flag_clr();
pal_trx_irq_en(); /* Enable transceiver main interrupt. */
#ifdef ENABLE_FTN_PLL_CALIBRATION
{
/* Handle PLL calibration and filter tuning. */
retval_t timer_status;
/* Calibration timer has already been stopped within this function. */
/* Start periodic calibration timer. */
timer_status = pal_timer_start(TAL_CALIBRATION,
TAL_CALIBRATION_TIMEOUT_US,
TIMEOUT_RELATIVE,
(FUNC_PTR())calibration_timer_handler_cb,
NULL);
if (timer_status != MAC_SUCCESS)
{
ASSERT("PLL calibration timer start problem" == 0);
}
}
#endif /* ENABLE_FTN_PLL_CALIBRATION */
return MAC_SUCCESS;
}
/*
* \brief Sets transceiver state
*
* \param trx_cmd needs to be one of the trx commands
*
* \return current trx state
*/
tal_trx_status_t set_trx_state(trx_cmd_t trx_cmd)
{
if (tal_trx_status == TRX_SLEEP) {
/*
* Since the wake-up procedure relies on the Awake IRQ and
* the global interrupts may be disabled at this point of time,
* we need to make sure that the global interrupts are enabled
* during wake-up procedure.
* Once the TRX is awake, the original state of the global
*interrupts
* will be restored.
*/
/* Reset wake-up interrupt flag. */
if(CMD_SLEEP == trx_cmd)
{
return TRX_SLEEP;
}
tal_awake_end_flag = false;
/* Set callback function for the awake interrupt. */
pal_trx_irq_init((FUNC_PTR)trx_irq_awake_handler_cb);
/* The pending transceiver interrupts on the microcontroller are
*cleared. */
pal_trx_irq_flag_clr();
pal_trx_irq_en(); /* Enable transceiver main interrupt. */
/* Save current state of global interrupts. */
ENTER_CRITICAL_REGION();
/* Force enabling of global interrupts. */
ENABLE_GLOBAL_IRQ();
/* Leave trx sleep mode. */
PAL_SLP_TR_LOW();
/* Poll wake-up interrupt flag until set within ISR. */
while (!tal_awake_end_flag) {
}
/* Restore original state of global interrupts. */
LEAVE_CRITICAL_REGION();
/* Clear existing interrupts */
pal_trx_reg_read(RG_IRQ_STATUS);
/* Re-install default IRQ handler for main interrupt. */
pal_trx_irq_init((FUNC_PTR)trx_irq_handler_cb);
/* Re-enable regular interrupts except Awake-IRQ */
pal_trx_reg_write(RG_IRQ_MASK, TRX_IRQ_DEFAULT);
#if (ANTENNA_DIVERSITY == 1)
/* Enable antenna diversity. */
pal_trx_bit_write(SR_ANT_EXT_SW_EN, ANT_EXT_SW_ENABLE);
#endif
#ifdef EXT_RF_FRONT_END_CTRL
/* Enable RF front end control */
pal_trx_bit_write(SR_PA_EXT_EN, PA_EXT_ENABLE);
#endif
if ((trx_cmd == CMD_TRX_OFF) ||
(trx_cmd == CMD_FORCE_TRX_OFF)) {
tal_trx_status = TRX_OFF;
return TRX_OFF;
}
}
switch (trx_cmd) { /* requested state */
case CMD_SLEEP:
pal_trx_reg_write(RG_TRX_STATE, CMD_FORCE_TRX_OFF);
#if (ANTENNA_DIVERSITY == 1)
/* Disable antenna diversity: sets pulls */
pal_trx_bit_write(SR_ANT_EXT_SW_EN, ANT_EXT_SW_DISABLE);
#endif
#ifdef EXT_RF_FRONT_END_CTRL
/* Disable RF front end control */
pal_trx_bit_write(SR_PA_EXT_EN, PA_EXT_DISABLE);
#endif
#ifndef SW_CONTROLLED_CSMA
{
uint16_t rand_value;
/*
* Init the SEED value of the CSMA backoff algorithm.
*/
rand_value = (uint16_t)rand();
pal_trx_reg_write(RG_CSMA_SEED_0, (uint8_t)rand_value);
pal_trx_bit_write(SR_CSMA_SEED_1,
(uint8_t)(rand_value >> 8));
}
#endif
/* Clear existing interrupts */
pal_trx_reg_read(RG_IRQ_STATUS);
/*
* Enable Awake_end interrupt.
* This is used for save wake-up from sleep later.
*/
pal_trx_bit_write(SR_IRQ_MASK, TRX_IRQ_CCA_ED_READY);
PAL_WAIT_1_US();
PAL_SLP_TR_HIGH();
pal_timer_delay(TRX_OFF_TO_SLEEP_TIME_CLKM_CYCLES);
tal_trx_status = TRX_SLEEP;
return TRX_SLEEP; /* transceiver register cannot be read during
*TRX_SLEEP */
case CMD_TRX_OFF:
switch (tal_trx_status) {
case TRX_OFF:
break;
default:
pal_trx_reg_write(RG_TRX_STATE, CMD_TRX_OFF);
PAL_WAIT_1_US();
break;
}
break;
case CMD_FORCE_TRX_OFF:
switch (tal_trx_status) {
case TRX_OFF:
break;
default:
pal_trx_reg_write(RG_TRX_STATE, CMD_FORCE_TRX_OFF);
PAL_WAIT_1_US();
break;
}
break;
case CMD_PLL_ON:
switch (tal_trx_status) {
case PLL_ON:
break;
case TRX_OFF:
switch_pll_on();
break;
case RX_ON:
case RX_AACK_ON:
case TX_ARET_ON:
pal_trx_reg_write(RG_TRX_STATE, CMD_PLL_ON);
PAL_WAIT_1_US();
break;
case BUSY_RX:
case BUSY_TX:
case BUSY_RX_AACK:
case BUSY_TX_ARET:
/* do nothing if trx is busy */
break;
default:
Assert("state transition not handled" == 0);
break;
}
break;
case CMD_FORCE_PLL_ON:
switch (tal_trx_status) {
case TRX_OFF:
switch_pll_on();
break;
case PLL_ON:
break;
default:
pal_trx_reg_write(RG_TRX_STATE, CMD_FORCE_PLL_ON);
break;
}
break;
case CMD_RX_ON:
switch (tal_trx_status) {
case RX_ON:
break;
case PLL_ON:
case RX_AACK_ON:
case TX_ARET_ON:
pal_trx_reg_write(RG_TRX_STATE, CMD_RX_ON);
PAL_WAIT_1_US();
break;
case TRX_OFF:
switch_pll_on();
pal_trx_reg_write(RG_TRX_STATE, CMD_RX_ON);
PAL_WAIT_1_US();
break;
case BUSY_RX:
case BUSY_TX:
case BUSY_RX_AACK:
case BUSY_TX_ARET:
/* do nothing if trx is busy */
break;
default:
Assert("state transition not handled" == 0);
break;
}
break;
case CMD_RX_AACK_ON:
switch (tal_trx_status) {
case RX_AACK_ON:
break;
case TX_ARET_ON:
case PLL_ON:
pal_trx_reg_write(RG_TRX_STATE, CMD_RX_AACK_ON);
PAL_WAIT_1_US();
break;
case TRX_OFF:
switch_pll_on(); /* state change from TRX_OFF to
* RX_AACK_ON can be done directly, too */
pal_trx_reg_write(RG_TRX_STATE, CMD_RX_AACK_ON);
PAL_WAIT_1_US();
break;
case RX_ON:
pal_trx_reg_write(RG_TRX_STATE, CMD_PLL_ON);
PAL_WAIT_1_US();
/* check if state change could be applied */
tal_trx_status = (tal_trx_status_t)pal_trx_bit_read(
SR_TRX_STATUS);
if (tal_trx_status != PLL_ON) {
return tal_trx_status;
}
pal_trx_reg_write(RG_TRX_STATE, CMD_RX_AACK_ON);
PAL_WAIT_1_US();
break;
case BUSY_RX:
case BUSY_TX:
case BUSY_RX_AACK:
case BUSY_TX_ARET:
/* do nothing if trx is busy */
break;
default:
Assert("state transition not handled" == 0);
break;
}
break;
case CMD_TX_ARET_ON:
switch (tal_trx_status) {
case TX_ARET_ON:
break;
case PLL_ON:
pal_trx_reg_write(RG_TRX_STATE, CMD_TX_ARET_ON);
PAL_WAIT_1_US();
break;
case RX_ON:
case RX_AACK_ON:
pal_trx_reg_write(RG_TRX_STATE, CMD_PLL_ON);
PAL_WAIT_1_US();
/* check if state change could be applied */
tal_trx_status = (tal_trx_status_t)pal_trx_bit_read(
SR_TRX_STATUS);
if (tal_trx_status != PLL_ON) {
return tal_trx_status;
}
pal_trx_reg_write(RG_TRX_STATE, CMD_TX_ARET_ON);
PAL_WAIT_1_US();
break;
case TRX_OFF:
switch_pll_on(); /* state change from TRX_OFF to
* TX_ARET_ON can be done directly, too */
pal_trx_reg_write(RG_TRX_STATE, CMD_TX_ARET_ON);
PAL_WAIT_1_US();
break;
case BUSY_RX:
case BUSY_TX:
case BUSY_RX_AACK:
case BUSY_TX_ARET:
/* do nothing if trx is busy */
break;
default:
Assert("state transition not handled" == 0);
break;
}
break;
default:
/* CMD_NOP, CMD_TX_START */
Assert("trx command not handled" == 0);
break;
}
do {
tal_trx_status = (tal_trx_status_t)pal_trx_bit_read(
SR_TRX_STATUS);
} while (tal_trx_status == STATE_TRANSITION_IN_PROGRESS);
return tal_trx_status;
} /* set_trx_state() */
/*
* \brief Resets TAL state machine and sets the default PIB values if requested
*
* \param set_default_pib Defines whether PIB values need to be set
* to its default values
*/
retval_t tal_reset(bool set_default_pib)
{
/*
* Do the reset stuff.
* Set the default PIBs depending on the given parameter
*set_default_pib.
*/
if (internal_tal_reset(set_default_pib) != MAC_SUCCESS) {
return FAILURE;
}
#if (MAC_SCAN_ED_REQUEST_CONFIRM == 1)
/* Stop the ED sample timer. */
#ifdef ENABLE_HIGH_PRIO_TMR
pal_stop_high_priority_timer(TAL_ED_SAMPLE_TIMER);
#endif /* ENABLE_HIGH_PRIO_TMR */
#endif /* (MAC_SCAN_ED_REQUEST_CONFIRM == 1) */
ENTER_CRITICAL_REGION();
tal_timers_stop();
LEAVE_CRITICAL_REGION();
/* Clear TAL Incoming Frame queue and free used buffers. */
while (tal_incoming_frame_queue.size > 0) {
buffer_t *frame = qmm_queue_remove(&tal_incoming_frame_queue,
NULL);
if (NULL != frame) {
bmm_buffer_free(frame);
}
}
/*
* Configure interrupt handling.
* Install a handler for the transceiver interrupt.
*/
pal_trx_irq_init((FUNC_PTR)trx_irq_handler_cb);
/* The pending transceiver interrupts on the microcontroller are
*cleared. */
pal_trx_irq_flag_clr();
pal_trx_irq_en(); /* Enable transceiver main interrupt. */
#ifdef ENABLE_FTN_PLL_CALIBRATION
{
/* Handle PLL calibration and filter tuning. */
retval_t timer_status;
/* Calibration timer has already been stopped within this
*function. */
/* Start periodic calibration timer.*/
timer_status = pal_timer_start(TAL_CALIBRATION,
TAL_CALIBRATION_TIMEOUT_US,
TIMEOUT_RELATIVE,
(FUNC_PTR)calibration_timer_handler_cb,
NULL);
if (timer_status != MAC_SUCCESS) {
Assert("PLL calibration timer start problem" == 0);
}
}
#endif /* ENABLE_FTN_PLL_CALIBRATION */
return MAC_SUCCESS;
}
/*
* \brief Initializes the TAL
*
* This function is called to initialize the TAL. The transceiver is
* initialized, the TAL PIBs are set to their default values, and the TAL state
* machine is set to TAL_IDLE state.
*
* \return MAC_SUCCESS if the transceiver state is changed to TRX_OFF and the
* current device part number and version number are correct;
* FAILURE otherwise
*/
retval_t tal_init(void)
{
/* Init the PAL and by this means also the transceiver interface */
if (pal_init() != MAC_SUCCESS) {
return FAILURE;
}
if (trx_init() != MAC_SUCCESS) {
return FAILURE;
}
if (tal_timer_init() != MAC_SUCCESS) {
return FAILURE;
}
#ifdef ENABLE_STACK_NVM
pal_ps_get(INTERN_EEPROM, EE_IEEE_ADDR, 8, &tal_pib.IeeeAddress);
#endif
/*
* For systems including the AT86RF230B the random seed generation
* cannot be done using a dedicated hardware feature.
* Therefore all random seed generation needs to be done by special
* means (e.g. utilization of ADC) that generate a random value only
* within a certain range.
*
* In case the node already has a valid IEEE address (i.e. an IEEE
* address which is different from 0x0000000000000000 or
* 0xFFFFFFFFFFFFFFFF), this IEEE address (the lower 16 bit)
* shall be used as seed for srand(), since each node should have a
*unique
* IEEE address.
* In this case srand() is called directly and function
*tal_generate_rand_seed()
* is not called.
*
* Note: This behaviour is different in all other TALs, since in these
* cases the seed for srand() is always generated based on transceiver
* hardware support.
*/
#ifndef DISABLE_IEEE_ADDR_CHECK
if ((tal_pib.IeeeAddress == 0x0000000000000000) ||
(tal_pib.IeeeAddress == 0xFFFFFFFFFFFFFFFF)
) {
/*
* Generate a seed for the random number generator in function
*rand().
* This is required (for example) as seed for the CSMA-CA
*algorithm.
*/
tal_generate_rand_seed();
/*
* Now that we have generated a random seed, we can generate a
*random
* IEEE address for this node.
*/
do {
/*
* In case no valid IEEE address is available, a random
* IEEE address will be generated to be able to run the
* applications for demonstration purposes.
* In production code this can be omitted.
*/
/*
* The proper seed for function rand() has already been
*generated
* in function tal_generate_rand_seed().
*/
uint8_t *ptr_pib = (uint8_t *)&tal_pib.IeeeAddress;
for (uint8_t i = 0; i < 8; i++) {
*ptr_pib++ = (uint8_t)rand();
/*
* Note:
* Even if casting the 16 bit rand value back to
*8 bit,
* and running the loop 8 timers (instead of
*only 4 times)
* may look cumbersome, it turns out that the
*code gets
* smaller using 8-bit here.
* And timing is not an issue at this place...
*/
}
}
/* Check if a valid IEEE address is available. */
while ((tal_pib.IeeeAddress == 0x0000000000000000) ||
(tal_pib.IeeeAddress == 0xFFFFFFFFFFFFFFFF)
);
} else {
/* Valid IEEE address, so no need to generate a new random seed.
**/
uint16_t cur_rand_seed = (uint16_t)tal_pib.IeeeAddress;
srand(cur_rand_seed);
}
#else
/*
* No check for a valid IEEE address done, so directly create a seed
* for srand().
*/
tal_generate_rand_seed();
#endif
/*
* Do the reset stuff.
* Set the default PIBs.
*/
if (internal_tal_reset(true) != MAC_SUCCESS) {
return FAILURE;
}
pal_trx_reg_read(RG_IRQ_STATUS); /* clear pending irqs, dummy read */
/*
* Configure interrupt handling.
* Install a handler for the transceiver interrupt.
*/
pal_trx_irq_init((FUNC_PTR)trx_irq_handler_cb);
pal_trx_irq_en(); /* Enable transceiver main interrupt. */
/* Initialize the buffer management module and get a buffer to store
*reveived frames. */
bmm_buffer_init();
tal_rx_buffer = bmm_buffer_alloc(LARGE_BUFFER_SIZE);
/* Init incoming frame queue */
#ifdef ENABLE_QUEUE_CAPACITY
qmm_queue_init(&tal_incoming_frame_queue,
TAL_INCOMING_FRAME_QUEUE_CAPACITY);
#else
qmm_queue_init(&tal_incoming_frame_queue);
#endif /* ENABLE_QUEUE_CAPACITY */
return MAC_SUCCESS;
} /* tal_init() */
/*
* \brief Initializes the TAL
*
* This function is called to initialize the TAL. The transceiver is
* initialized, the TAL PIBs are set to their default values, and the TAL state
* machine is set to TAL_IDLE state.
*
* \return MAC_SUCCESS if the transceiver state is changed to TRX_OFF and the
* current device part number and version number are correct;
* FAILURE otherwise
*/
retval_t tal_init(void)
{
/* Init the PAL and by this means also the transceiver interface */
if (pal_init() != MAC_SUCCESS) {
return FAILURE;
}
if (trx_init() != MAC_SUCCESS) {
return FAILURE;
}
if (tal_timer_init() != MAC_SUCCESS) {
return FAILURE;
}
#ifdef ENABLE_STACK_NVM
pal_ps_get(INTERN_EEPROM, EE_IEEE_ADDR, 8, &tal_pib.IeeeAddress);
#endif
/*
* Do the reset stuff.
* Set the default PIBs.
* Generate random seed.
*/
if (internal_tal_reset(true) != MAC_SUCCESS) {
return FAILURE;
}
#ifndef DISABLE_IEEE_ADDR_CHECK
/* Check if a valid IEEE address is available. */
/*
* This while loop is on purpose, since just in the
* rare case that such an address is randomly
* generated again, we must repeat this.
*/
uint64_t invalid_ieee_address;
memset((uint8_t *)&invalid_ieee_address, 0xFF, sizeof(invalid_ieee_address));
while ((tal_pib.IeeeAddress == 0x0000000000000000) ||
(tal_pib.IeeeAddress == invalid_ieee_address)){
/*
* In case no valid IEEE address is available, a random
* IEEE address will be generated to be able to run the
* applications for demonstration purposes.
* In production code this can be omitted.
*/
/*
* The proper seed for function rand() has already been
*generated
* in function tal_generate_rand_seed().
*/
uint8_t *ptr_pib = (uint8_t *)&tal_pib.IeeeAddress;
for (uint8_t i = 0; i < 8; i++) {
*ptr_pib++ = (uint8_t)rand();
/*
* Note:
* Even if casting the 16 bit rand value back to 8 bit,
* and running the loop 8 timers (instead of only 4
*times)
* may look cumbersome, it turns out that the code gets
* smaller using 8-bit here.
* And timing is not an issue at this place...
*/
}
}
#endif /* #ifndef DISABLE_IEEE_ADDR_CHECK */
#ifdef ENABLE_STACK_NVM
pal_ps_set(EE_IEEE_ADDR, 8, &tal_pib.IeeeAddress);
#endif
/*
* Configure interrupt handling.
* Install a handler for the main transceiver interrupt.
*/
pal_trx_irq_init((FUNC_PTR)trx_irq_handler_cb);
pal_trx_irq_en(); /* Enable main transceiver interrupt. */
#if ((defined BEACON_SUPPORT) || (defined ENABLE_TSTAMP)) && \
(DISABLE_TSTAMP_IRQ == 0)
/* Configure time stamp interrupt.
* The timestamping is only required for
* - beaconing networks or if timestamping is explicitly enabled,
* - and if the time stamp interrupt is not explicitly disabled.
*/
pal_trx_irq_init_tstamp((FUNC_PTR)trx_irq_timestamp_handler_cb);
pal_trx_irq_en_tstamp(); /* Enable timestamp interrupt. */
#endif
/* Initialize the buffer management module and get a buffer to store
*reveived frames. */
bmm_buffer_init();
tal_rx_buffer = bmm_buffer_alloc(LARGE_BUFFER_SIZE);
/* Init incoming frame queue */
#ifdef ENABLE_QUEUE_CAPACITY
qmm_queue_init(&tal_incoming_frame_queue,
TAL_INCOMING_FRAME_QUEUE_CAPACITY);
#else
qmm_queue_init(&tal_incoming_frame_queue);
#endif /* ENABLE_QUEUE_CAPACITY */
#ifdef ENABLE_TFA
tfa_init();
#endif
return MAC_SUCCESS;
} /* tal_init() */
/**
* \brief Interrupt handler for ACK reception
*
* \param parameter Unused callback parameter
*/
static void ack_reception_handler_cb(void *parameter)
{
trx_irq_reason_t trx_irq_cause;
if (tal_csma_state == TX_DONE_NO_ACK) {
return; /* ack expiration timer has already been fired */
}
trx_irq_cause = (trx_irq_reason_t)pal_trx_reg_read(RG_IRQ_STATUS);
if (trx_irq_cause & TRX_IRQ_TRX_END) {
retval_t timer_status;
switch (tal_csma_state) {
case FRAME_SENDING_WITH_ACK:
set_trx_state(CMD_RX_ON);
timer_status
= pal_timer_start(TAL_ACK_WAIT_TIMER,
TAL_CONVERT_SYMBOLS_TO_US(
TAL_ACK_WAIT_DURATION_DEFAULT),
TIMEOUT_RELATIVE,
(FUNC_PTR)ack_timer_expiry_handler_cb,
NULL);
if (timer_status == MAC_SUCCESS) {
tal_csma_state = WAITING_FOR_ACK;
} else if (timer_status == PAL_TMR_ALREADY_RUNNING) {
tal_csma_state = WAITING_FOR_ACK;
} else {
tal_csma_state = TX_DONE_NO_ACK;
Assert("timer start failed" == 0);
}
/* debug pin to switch on: define ENABLE_DEBUG_PINS,
*pal_config.h */
PIN_TX_END();
PIN_ACK_WAITING_START();
break;
case WAITING_FOR_ACK:
{
uint8_t ack_frame[ACK_FRAME_LEN + LENGTH_FIELD_LEN];
/*
* Read the frame buffer, identify if this is an ACK
*frame,
* and get the sequence number.
* Üpload the frame from the transceiver.
*/
pal_trx_frame_read(ack_frame,
(ACK_FRAME_LEN +
LENGTH_FIELD_LEN));
/* Check if the uploaded frame is an ACK frame */
if ((ack_frame[1] & ACK_FRAME) != ACK_FRAME) {
/* The received frame is not an ACK frame */
return;
}
/* check CRC */
if (pal_trx_bit_read(SR_RX_CRC_VALID) != CRC16_VALID) {
return;
}
/* check the sequence number */
if (ack_frame[3] == tal_frame_to_tx[SEQ_NUMBER_POS]) {
/*
* If we are here, the ACK is valid and matches
* the transmitted sequence number.
*/
pal_timer_stop(TAL_ACK_WAIT_TIMER);
#if (_DEBUG_ > 0)
if (pal_is_timer_running(TAL_ACK_WAIT_TIMER)) {
Assert("Ack timer running" == 0);
}
#endif
/* restore the interrupt handler */
pal_trx_irq_init((FUNC_PTR)trx_irq_handler_cb);
pal_trx_irq_en();
if (NULL != tal_rx_buffer) {
pal_trx_reg_write(RG_TRX_STATE,
CMD_RX_AACK_ON);
} else {
tal_rx_on_required = true;
}
/* debug pin to switch on: define
*ENABLE_DEBUG_PINS, pal_config.h */
PIN_ACK_OK_START();
if (ack_frame[1] & FCF_FRAME_PENDING) {
tal_csma_state = TX_DONE_FRAME_PENDING;
} else {
tal_csma_state = TX_DONE_SUCCESS;
}
/* debug pin to switch on: define
*ENABLE_DEBUG_PINS, pal_config.h */
PIN_ACK_OK_END();
PIN_ACK_WAITING_END();
}
}
break;
case FRAME_SENDING_NO_ACK:
/* Tx is done */
/* debug pin to switch on: define ENABLE_DEBUG_PINS,
*pal_config.h */
PIN_TX_END();
tal_csma_state = TX_DONE_SUCCESS;
break;
default:
Assert("unknown tal_csma_state" == 0);
break;
}
} else { /* other interrupt than TRX_END */
/* no interest in any other interrupt */
return;
}
parameter = parameter; /* Keep compiler happy. */
}
/**
* \brief State machine handling slotted CSMA
*/
void slotted_csma_state_handling(void)
{
switch (tal_csma_state) {
case BACKOFF_WAITING_FOR_CCA_TIMER:
break;
case BACKOFF_WAITING_FOR_BEACON:
/*
* Do not perform any operation and wait until the next beacon
* reception. If several beacons are not received, the beacon
*loss
* timer expires and stops the entire transaction.
*/
break;
case CSMA_HANDLE_BEACON:
/* debug pin to switch on: define ENABLE_DEBUG_PINS,
*pal_config.h */
PIN_WAITING_FOR_BEACON_END();
PIN_BEACON_LOSS_TIMER_END();
pal_timer_stop(TAL_CSMA_BEACON_LOSS_TIMER);
csma_backoff_calculation();
break;
case CSMA_ACCESS_FAILURE:
NB++;
BE++;
/* ensure that BE is no more than macMaxBE */
if (BE > tal_pib.MaxBE) { /* macMaxBE */
BE = tal_pib.MaxBE; /* macMaxBE */
}
if (NB > macMaxCSMABackoffs) {
/* terminate with channel access failure */
tx_done(MAC_CHANNEL_ACCESS_FAILURE);
} else {
/* restart backoff */
csma_backoff_calculation();
}
break;
case NO_BEACON_TRACKING:
/* terminate with channel access failure */
tx_done(MAC_CHANNEL_ACCESS_FAILURE);
break;
case FRAME_SENDING_WITH_ACK:
case FRAME_SENDING_NO_ACK:
/* waiting for end of frame transmission */
break;
case WAITING_FOR_ACK:
/* waiting for ACK reception */
break;
case TX_DONE_SUCCESS:
tx_done(MAC_SUCCESS);
break;
case TX_DONE_FRAME_PENDING:
tx_done(TAL_FRAME_PENDING);
break;
case TX_DONE_NO_ACK:
if (number_of_tx_retries < tal_pib.MaxFrameRetries) {
number_of_tx_retries++;
set_trx_state(CMD_RX_AACK_ON);
/*
* While continuing with CSMA, handle trx irq with
*regular isr.
* Install a handler for the transceiver interrupt.
*/
pal_trx_irq_init((FUNC_PTR)trx_irq_handler_cb);
pal_trx_reg_read(RG_TRX_STATUS);
pal_trx_irq_en();
/*
* Start the entire CSMA procedure again,
* but do not reset the number of transmission attempts.
*/
BE++;
/* ensure that BE is no more than macMaxBE */
if (BE > tal_pib.MaxBE) { /* macMaxBE */
BE = tal_pib.MaxBE; /* macMaxBE */
}
NB = 0;
remaining_backoff_periods
= (uint8_t)(rand() & ((1 << BE) - 1));
csma_backoff_calculation();
} else {
tx_done(MAC_NO_ACK);
}
PIN_NO_ACK_END();
break;
default:
Assert("INVALID CSMA status" == 0);
break;
}
} /* csma_ca_state_handling() */