diff --git a/tasmota/core_esp8266_waveform.h b/tasmota/core_esp8266_waveform.h new file mode 100644 index 000000000..61cb99966 --- /dev/null +++ b/tasmota/core_esp8266_waveform.h @@ -0,0 +1,89 @@ +/* + esp8266_waveform - General purpose waveform generation and control, + supporting outputs on all pins in parallel. + + Copyright (c) 2018 Earle F. Philhower, III. All rights reserved. + Copyright (c) 2020 Dirk O. Kaar. + + The core idea is to have a programmable waveform generator with a unique + high and low period (defined in microseconds or CPU clock cycles). TIMER1 is + set to 1-shot mode and is always loaded with the time until the next edge + of any live waveforms. + + Up to one waveform generator per pin supported. + + Each waveform generator is synchronized to the ESP clock cycle counter, not the + timer. This allows for removing interrupt jitter and delay as the counter + always increments once per 80MHz clock. Changes to a waveform are + contiguous and only take effect on the next waveform transition, + allowing for smooth transitions. + + This replaces older tone(), analogWrite(), and the Servo classes. + + Everywhere in the code where "ccy" or "ccys" is used, it means ESP.getCycleCount() + clock cycle count, or an interval measured in CPU clock cycles, but not TIMER1 + cycles (which may be 2 CPU clock cycles @ 160MHz). + + This library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + This library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with this library; if not, write to the Free Software + Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA +*/ + +#include + +#ifndef __ESP8266_WAVEFORM_H +#define __ESP8266_WAVEFORM_H + +#ifdef __cplusplus +extern "C" { +#endif + +// Start or change a waveform of the specified high and low times on specific pin. +// If runtimeUS > 0 then automatically stop it after that many usecs, relative to the next +// full period. +// If waveform is not yet started on pin, and on pin == alignPhase a waveform is running, +// the new waveform is started at phaseOffsetUS phase offset, in microseconds, to that. +// Setting autoPwm to true allows the wave generator to maintain PWM duty to idle cycle ratio +// under load, for applications where frequency or duty cycle must not change, leave false. +// Returns true or false on success or failure. +int startWaveform(uint8_t pin, uint32_t timeHighUS, uint32_t timeLowUS, + uint32_t runTimeUS = 0, int8_t alignPhase = -1, uint32_t phaseOffsetUS = 0, bool autoPwm = false); +// Start or change a waveform of the specified high and low CPU clock cycles on specific pin. +// If runtimeCycles > 0 then automatically stop it after that many CPU clock cycles, relative to the next +// full period. +// If waveform is not yet started on pin, and on pin == alignPhase a waveform is running, +// the new waveform is started at phaseOffsetCcys phase offset, in CPU clock cycles, to that. +// Setting autoPwm to true allows the wave generator to maintain PWM duty to idle cycle ratio +// under load, for applications where frequency or duty cycle must not change, leave false. +// Returns true or false on success or failure. +int startWaveformClockCycles(uint8_t pin, uint32_t timeHighCcys, uint32_t timeLowCcys, + uint32_t runTimeCcys = 0, int8_t alignPhase = -1, uint32_t phaseOffsetCcys = 0, bool autoPwm = false); +// Stop a waveform, if any, on the specified pin. +// Returns true or false on success or failure. +int stopWaveform(uint8_t pin); + +// Add a callback function to be called on *EVERY* timer1 trigger. The +// callback returns the number of microseconds until the next desired call. +// However, since it is called every timer1 interrupt, it may be called +// again before this period. It should therefore use the ESP Cycle Counter +// to determine whether or not to perform an operation. +// Pass in NULL to disable the callback and, if no other waveforms being +// generated, stop the timer as well. +// Make sure the CB function has the ICACHE_RAM_ATTR decorator. +void setTimer1Callback(uint32_t (*fn)()); + +#ifdef __cplusplus +} +#endif + +#endif