Esempio n. 1
0
File: tal_ed.c Progetto: bswe/6.1
/*
 * \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;
}
Esempio n. 2
0
/**
 * @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;
        }
    }

    set_trx_state(CMD_FORCE_PLL_ON);
    pal_trx_bit_write(SR_RX_PDT_DIS, RX_DISABLE);
    pal_trx_irq_flag_clr_cca_ed();
    pal_trx_irq_init_cca_ed((FUNC_PTR)trx_ed_irq_handler_cb);
    pal_trx_reg_write(RG_IRQ_MASK, TRX_IRQ_CCA_ED_READY);

    /* 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_reg_write(RG_IRQ_MASK, TRX_IRQ_DEFAULT);

        return FAILURE;
    }

    /* 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;

    // write dummy value to start measurement
    pal_trx_reg_write(RG_PHY_ED_LEVEL, 0xFF);

    return MAC_SUCCESS;
}