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Fix for pulse width bug when changing from high to low frequencies if there was an overrun

This commit is contained in:
ZodiusInfuser 2022-03-10 05:55:56 +00:00
parent d96db62353
commit 65268098c6
1 changed files with 10 additions and 2 deletions
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12
drivers/pwm/pwm_cluster.cpp
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@ -387,7 +387,7 @@ void PWMCluster::load_pwm() {
// Invert this channel's initial state if it's polarity invert is set
if(state.polarity) {
pin_states |= (1u << channel); // Set the pin
pin_states |= (1u << channel_to_pin_map[channel]); // Set the pin
}
uint channel_start = state.offset;
@ -404,19 +404,21 @@ void PWMCluster::load_pwm() {
// Did the previous sequence overrun the wrap level?
if(state.overrun > 0) {
// Flip the initial state so the pin starts "high" (or "low" if polarity inverted)
pin_states ^= (1u << channel);
pin_states ^= (1u << channel_to_pin_map[channel]);
// Check for a few edge cases when pulses change length across the wrap level
// Not entirely sure I understand which statements does what, but they seem to work
if((channel_end >= channel_start) || (state.overrun > channel_end)) {
// Add a transition to "low" (or "high" if polarity inverted) at the overrun level of the previous sequence
PWMCluster::sorted_insert(transitions, data_size, TransitionData(channel, state.overrun, state.polarity));
//printf("C = %d, Added Low at %d\n", channel, state.overrun);
}
}
if(state.level > 0 && channel_start < wrap_level) {
// Add a transition to "high" (or "low" if polarity inverted) at the start level
PWMCluster::sorted_insert(transitions, data_size, TransitionData(channel, channel_start, !state.polarity));
//printf("C = %d, Added High at %d\n", channel, channel_start);
// If the channel has overrun the wrap level, record by how much
if(channel_end < channel_start) {
@ -427,7 +429,10 @@ void PWMCluster::load_pwm() {
if(state.level < wrap_level) {
// Add a transition to "low" (or "high" if polarity inverted) at the end level
PWMCluster::sorted_insert(transitions, data_size, TransitionData(channel, channel_end, state.polarity));
//printf("C = %d, Added Low at %d\n", channel, channel_end);
}
//printf("C = %d, Start = %d, End = %d, Overrun = %d\n", channel, channel_start, channel_end, state.overrun);
}
// Introduce "Loading Zone" transitions to the end of the sequence to
@ -518,6 +523,9 @@ void PWMCluster::load_pwm() {
// Record the looping pin states
looping_mask[write_index] = pin_states;
//BUG It's not just the first one that needs overriding! D'oh!
// It could be a whole load of pulses that need updating to account for when multiple pulses pass the looping line
// May be best to have an intermediary sequence?
}
else {
// There were no transitions (either because there was a zero wrap, or no channels because there was a zero wrap?),