Search found 157 matches

by eriksl
Mon Sep 12, 2016 9:58 pm
Forum: General Q&A
Topic: PWM, Sigma_Delta reference clocks
Replies: 2
Views: 2662

Re: PWM, Sigma_Delta reference clocks

The frequency of PWM is directly and linearly related to the period of the PWM. The ESP8266 runs at 80 MHz normally, it can run on 160 MHz if you want to. The timer clock always runs at 80 MHz though and the practical lowest divisor is 16, which makes a raw rate of 5 MHz or a period of 200 nanosecon...
by eriksl
Mon Sep 12, 2016 9:45 pm
Forum: ESP8266 SDK
Topic: espmissingincludes.h How long this will continue?!!
Replies: 4
Views: 3785

Re: espmissingincludes.h How long this will continue?!!

+1!

Problem is not only the "warnings", in some cases the compiler will generate the wrong code, if the arguments are not simple pointers, int's or doubles -> crash.
by eriksl
Mon Sep 12, 2016 9:40 pm
Forum: ESP8266 SDK
Topic: os_bzero() detecting correct length issue
Replies: 4
Views: 3766

Re: os_bzero() detecting correct length issue

I am curious as of why the TS thinks bzero (or os_bzero) can be called with only one argument? See man bzero, it needs both the pointer and the length. It could very well be that bzero calls memset or the other way around, there is no real difference in semantics. The REAL issue here is, like often,...
by eriksl
Mon Sep 12, 2016 9:24 pm
Forum: ESP8266 SDK
Topic: NON-OS 1.5.4 (16_05_20) PWM bug
Replies: 13
Views: 13638

Re: NON-OS 1.5.4 (16_05_20) PWM bug

I switched to my own implementation now (for various reasons), so the problem is not relevant anymore.
by eriksl
Sat Aug 27, 2016 1:08 am
Forum: ESP8266 SDK
Topic: Strange behaviour FRC1 timer / interrupt handler
Replies: 3
Views: 2836

Re: Strange behaviour FRC1 timer / interrupt handler

When I "or" 0x01 into the value that is written into FRC1_CTRL_ADDRESS (+ PERIPHS_TIMER_BASEADDR of course), it works. According to the "documentation" (ehhhrmm, just examples found here and there), LEVEL_INT would be 0x1 and EDGE_INT would be 0x0. It seems it's the other way aro...
by eriksl
Fri Aug 26, 2016 11:26 pm
Forum: ESP8266 SDK
Topic: Strange behaviour FRC1 timer / interrupt handler
Replies: 3
Views: 2836

Re: Strange behaviour FRC1 timer / interrupt handler

Using this function I found: static inline uint32_t ETS_INTR_ENABLED(void) // FIXME { uint32_t enabled; __asm__ __volatile__("esync; rsr %0,intenable":"=a" (enabled)); return enabled; } I can see that the FRC1 interrupts are enabled. Without enabling FRC1 interrupts, it reads 521...
by eriksl
Tue Aug 23, 2016 6:42 pm
Forum: ESP8266 SDK
Topic: Strange behaviour FRC1 timer / interrupt handler
Replies: 3
Views: 2836

Re: Strange behaviour FRC1 timer / interrupt handler

Nobody at Espressif got a clue? I copied this code in various variants from examples (because of documentation lacking...), and apparently it does work for those people... I deactivated all code that does something with interrupts, i.e. the UART handler and the code that is run by os_timer_arm etc. ...
by eriksl
Fri Aug 19, 2016 6:10 pm
Forum: ESP8266 SDK
Topic: Strange behaviour FRC1 timer / interrupt handler
Replies: 3
Views: 2836

Strange behaviour FRC1 timer / interrupt handler

When I make a handler function for the FRC1 timer interrupt, it acts strangely, I can't explain. Please help. The only thing the handler does (for the moment) is count how many times it has been called (counter++). It does not clear an interrupt mask and also it does not reload the timer, so it migh...
by eriksl
Sun Aug 14, 2016 3:57 pm
Forum: Documentation Request
Topic: TIMERS
Replies: 6
Views: 11774

Re: TIMERS

Pratik, if you could shed any light on the most low-level operation of timers, it would be VERY VERY much appreciated! I understand your concerns, you should know in my case I am using the "bare metal" as much as possible, so there is no RTOS, and no AT code. Also I am moving away from the...
by eriksl
Wed Aug 10, 2016 8:11 pm
Forum: Documentation Request
Topic: TIMERS
Replies: 6
Views: 11774

TIMERS

Hello All, I am missing some detailed information about the hardware (!) timers. Sometimes the software timers or the sdk interface are just not enough. Coming from ATMega devices, where the timers are very thorougly documented and easy to use. This is the information that I gathered, please correct...

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