Enhance: Support ESP8266
mikaelpatel opened this issue · comments
This could be done by using the continuation stack support (cont.h https://github.com/esp8266/Arduino/blob/master/cores/esp8266/cont.h).
By adding some missing defines in scheduler.h, I can use the lib on my ESP-12:
#elif defined(ARDUINO_ARCH_ESP8266)
/** Default stack size and stack max. */
static const size_t DEFAULT_STACK_SIZE = 512;
// https://github.com/esp8266/esp8266-wiki/wiki/Memory-Map
#define RAMSTART (0x3FFE8000)
#define RAMSIZE (0x14000)
#define RAMEND (RAMSTART + RAMSIZE - 1)
@soubok Thanks for the update. That was a neat solution. Have you run any of the examples or benchmarks? Cheers!
@mikaelpatel, at the moment I just tried to run 2 concurrent tasks with some serial output, nothing more.
@soubok Have you been able to run any of the examples and/or got your test with 2 concurrent tasks working? I am consider updating the library with the above definition but do not have any hardware to test this on.
@mikaelpatel I will test it on my esp8266 project with several continuations. Arduino for esp8266 does not manage continuations using a so elegant way.
@mikaelpatel Integration with continuation was not done. The proposal of the member @soubok is incomplete and values are wrong. However, setjmp and longjmp works well. Stack need to be increased since context-switching consume more memory. Continuation on esp8266 Arduino shall be removed.
@anmaped Thanks for your effort testing this library for the ESP. I have done an update but not come around to pushing it mainly due to lack of testing. If I understand you correctly the suggested update (together with update of the ifdef in the source code) works. What default stack size would you suggest? 1K?
@mikaelpatel I will do a pull request with my changes. What examples do you want to test first ?
@anmaped Would appreciate if you could run and verify all the example sketches before the pull request. I do not have any ESP boards at this time.
@mikaelpatel Okay. I will do that. Before I need to ask Arduino esp8266 to weak four functions, esp_schedule, esp_yield, optimistic_yield, and finally loop_task.
Some preliminary results.
2. Yield main task: 1.04 us
3. Start a task: 1 us
4. Yield between two tasks: 1.66 us
5. Delay 10 ms and check increments: 0:0, nan us
6. Start 1 tasks: 6:1, 6.00 us
7. Yield and check increments: 3:2, 1.50 us
8. Delay 10 ms and check increments: 0:0, nan us
Delay is not yet implemented. There is room for one tasks only with standard Arduino esp8266 settings. The initiate scheduler cannot be called since is already initialized.