/**
* @brief 1-wire read bit callback.
* @note Must be called from PWM's ISR.
*
* @param[in] pwmp pointer to the @p PWMDriver object
* @param[in] owp pointer to the @p onewireDriver object
*
* @notapi
*/
static void ow_read_bit_cb(PWMDriver *pwmp, onewireDriver *owp) {
if (true == owp->reg.final_timeslot) {
osalSysLockFromISR();
pwmDisableChannelI(pwmp, owp->config->sample_channel);
osalThreadResumeI(&owp->thread, MSG_OK);
osalSysUnlockFromISR();
return;
}
else {
*owp->buf |= ow_read_bit(owp) << owp->reg.bit;
owp->reg.bit++;
if (8 == owp->reg.bit) {
owp->reg.bit = 0;
owp->buf++;
owp->reg.bytes--;
if (0 == owp->reg.bytes) {
owp->reg.final_timeslot = true;
osalSysLockFromISR();
/* Only master channel must be stopped here.
Sample channel will be stopped in next ISR call.
It is still needed to generate final interrupt. */
pwmDisableChannelI(pwmp, owp->config->master_channel);
osalSysUnlockFromISR();
}
}
}
}
static void pwm3cb(PWMDriver *pwmp) {
chSysLockFromIsr();
if (pwm_cycles > 8) {
pwmDisableChannelI(pwmp, 2);
pwmDisableChannelI(pwmp, 3);
tmp1 = (&GPT_DRIVER)->tim->CNT;
}
chSysUnlockFromIsr();
}
/**
* @brief 1-wire reset pulse callback.
* @note Must be called from PWM's ISR.
*
* @param[in] pwmp pointer to the @p PWMDriver object
* @param[in] owp pointer to the @p onewireDriver object
*
* @notapi
*/
static void ow_reset_cb(PWMDriver *pwmp, onewireDriver *owp) {
owp->reg.slave_present = (PAL_LOW == ow_read_bit(owp));
osalSysLockFromISR();
pwmDisableChannelI(pwmp, owp->config->sample_channel);
osalThreadResumeI(&owp->thread, MSG_OK);
osalSysUnlockFromISR();
}
/**
* @brief Disables a PWM channel and its notification.
* @pre The PWM unit must have been activated using @p pwmStart().
* @post The channel is disabled and its output line returned to the
* idle state.
* @note Depending on the hardware implementation this function has
* effect starting on the next cycle (recommended implementation)
* or immediately (fallback implementation).
*
* @param[in] pwmp pointer to a @p PWMDriver object
* @param[in] channel PWM channel identifier (0...channels-1)
*
* @api
*/
void pwmDisableChannel(PWMDriver *pwmp, pwmchannel_t channel) {
osalDbgCheck((pwmp != NULL) && (channel < pwmp->channels));
osalSysLock();
osalDbgAssert(pwmp->state == PWM_READY, "not ready");
pwmDisableChannelI(pwmp, channel);
osalSysUnlock();
}
/*
* PWM callbacks.
*/
static void pwm1cb(PWMDriver *pwmp) {
(void)pwmp;
chSysLockFromIsr();
pwm_cycles++;
if (pwm_cycles > 160) {
pwmDisableChannelI(pwmp, 0);
pwm_cycles = 0;
extChannelEnableI(&EXT_DRIVER, ECHO);
tmp2 = (&GPT_DRIVER)->tim->CNT;
}
chSysUnlockFromIsr();
}
/**
* @brief 1-wire bit transmission callback.
* @note Must be called from PWM's ISR.
*
* @param[in] pwmp pointer to the @p PWMDriver object
* @param[in] owp pointer to the @p onewireDriver object
*
* @notapi
*/
static void ow_write_bit_cb(PWMDriver *pwmp, onewireDriver *owp) {
if (8 == owp->reg.bit) {
owp->buf++;
owp->reg.bit = 0;
owp->reg.bytes--;
if (0 == owp->reg.bytes) {
osalSysLockFromISR();
pwmDisableChannelI(pwmp, owp->config->master_channel);
osalSysUnlockFromISR();
/* used to prevent premature timer stop from userspace */
owp->reg.final_timeslot = true;
return;
}
}
/* wait until timer generate last pulse */
if (true == owp->reg.final_timeslot) {
#if ONEWIRE_USE_STRONG_PULLUP
if (owp->reg.need_pullup) {
owp->reg.state = ONEWIRE_PULL_UP;
owp->config->pullup_assert();
owp->reg.need_pullup = false;
}
#endif
osalSysLockFromISR();
osalThreadResumeI(&owp->thread, MSG_OK);
osalSysUnlockFromISR();
return;
}
ow_write_bit_I(owp, (*owp->buf >> owp->reg.bit) & 1);
owp->reg.bit++;
}
/**
* @brief 1-wire search ROM callback.
* @note Must be called from PWM's ISR.
*
* @param[in] pwmp pointer to the @p PWMDriver object
* @param[in] owp pointer to the @p onewireDriver object
*
* @notapi
*/
static void ow_search_rom_cb(PWMDriver *pwmp, onewireDriver *owp) {
onewire_search_rom_t *sr = &owp->search_rom;
if (0 == sr->reg.bit_step) { /* read direct bit */
sr->reg.bit_buf |= ow_read_bit(owp);
sr->reg.bit_step++;
}
else if (1 == sr->reg.bit_step) { /* read complement bit */
sr->reg.bit_buf |= ow_read_bit(owp) << 1;
sr->reg.bit_step++;
switch(sr->reg.bit_buf){
case 0b11:
/* no one device on bus or any other fail happened */
sr->reg.result = ONEWIRE_SEARCH_ROM_ERROR;
goto THE_END;
break;
case 0b01:
/* all slaves have 1 in this position */
store_bit(sr, 1);
ow_write_bit_I(owp, 1);
break;
case 0b10:
/* all slaves have 0 in this position */
store_bit(sr, 0);
ow_write_bit_I(owp, 0);
break;
case 0b00:
/* collision */
sr->reg.single_device = false;
ow_write_bit_I(owp, collision_handler(sr));
break;
}
}
else { /* start next step */
#if !ONEWIRE_SYNTH_SEARCH_TEST
ow_write_bit_I(owp, 1);
#endif
sr->reg.bit_step = 0;
sr->reg.bit_buf = 0;
}
/* one ROM successfully discovered */
if (64 == sr->reg.rombit) {
sr->reg.devices_found++;
sr->reg.search_iter = ONEWIRE_SEARCH_ROM_NEXT;
if (true == sr->reg.single_device)
sr->reg.result = ONEWIRE_SEARCH_ROM_LAST;
goto THE_END;
}
return; /* next search bit iteration */
THE_END:
#if ONEWIRE_SYNTH_SEARCH_TEST
(void)pwmp;
return;
#else
osalSysLockFromISR();
pwmDisableChannelI(pwmp, owp->config->master_channel);
pwmDisableChannelI(pwmp, owp->config->sample_channel);
osalThreadResumeI(&(owp)->thread, MSG_OK);
osalSysUnlockFromISR();
#endif
}