Search found 19 matches

by szguyer
Tue May 11, 2021 1:24 pm
Forum: ESP-IDF
Topic: Calling HAL functions directly?
Replies: 2
Views: 2670

Re: Calling HAL functions directly?

Ok, thanks. Do you have any other advice about how to handle this situation? Specifically, when you want to call an ESP-IDF function from an interrupt handler, and you want all the code to be in IRAM, but the function doesn't have that attribute.
by szguyer
Mon May 10, 2021 6:17 pm
Forum: ESP-IDF
Topic: Calling HAL functions directly?
Replies: 2
Views: 2670

Calling HAL functions directly?

I am working on the ESP32 support in FastLED, and I'm trying to figure out how to make sure that our interrupt handler code is all in IRAM. We are using the RMT peripheral to generate the signal for clockless LED chips, and the problem is that we call RMT functions in ESP-IDF that are not marked wit...
by szguyer
Mon Dec 07, 2020 3:40 am
Forum: ESP-IDF
Topic: ESP32 / RMT loosing ticks /
Replies: 4
Views: 6810

Re: ESP32 / RMT loosing ticks /

We've used this technique successfully in the ESP32 support for the FastLED library. BUT I've never set it up where rmt_set_tx_thr_intr_en is being given a value that isn't a multiple of 32 or 64. We don't use sentinels at all.(Or rather, we only use the special 0-value sentinel that indicates we ar...
by szguyer
Fri Dec 04, 2020 12:58 am
Forum: ESP-IDF
Topic: RMT functions not in IRAM
Replies: 0
Views: 1938

RMT functions not in IRAM

Hello, I have been working on improvements to the FastLED driver for ESP32 based on the RMT device, and I've run into a problem when our code is run in conjunction with flash-based file systems. Users are reporting that their programs occasionally trigger a cache access failure when attempting to wr...
by szguyer
Fri Jan 17, 2020 3:29 pm
Forum: ESP-IDF
Topic: Impact of concurrency constraints in SPI Flash interface
Replies: 5
Views: 7101

Re: Impact of concurrency constraints in SPI Flash interface

Most of our users are developing code in the Arduino IDE. And their level of programming expertise varies widely (many are beginners), so I would be reluctant to tell them to make changes to their dev environment. Really, the right answer is to figure out how to get around the GCC compiler bug, so t...
by szguyer
Thu Jan 16, 2020 6:48 pm
Forum: ESP-IDF
Topic: Impact of concurrency constraints in SPI Flash interface
Replies: 5
Views: 7101

Re: Impact of concurrency constraints in SPI Flash interface

Would it be reasonable to call spi_flash_op_lock() explicitly before I start a time-sensitive operation (and then spi_flash_op_unlock() at the end)? I just need some way to avoid flash operations shutting off the caches in the middle of the process of sending bits to the LED strips, since the timing...
by szguyer
Tue Jan 14, 2020 4:09 am
Forum: ESP-IDF
Topic: Impact of concurrency constraints in SPI Flash interface
Replies: 5
Views: 7101

Re: Impact of concurrency constraints in SPI Flash interface

Thanks Ivan! On the first point, how can I check to see if some other code is disabling the caches? What API is used to disable/enable them? Yes, you're right about the compiler issue -- it is not Xtensa specific. I'm not the one who discovered the problem, so I didn't investigate it in detail. We f...
by szguyer
Tue Jan 14, 2020 2:14 am
Forum: ESP-IDF
Topic: fast isr_handler during flash write or erase gives "Cache disabled but cached memory region accessed"
Replies: 5
Views: 6020

Re: fast isr_handler during flash write or erase gives "Cache disabled but cached memory region accessed"

This problem seems very similar to the one I have been encountering (see post https://www.esp32.com/viewtopic.php?f=13&t=13855 from yesterday). I think the relevant documentation is here: https://github.com/espressif/esp-idf/tree/master/components/spi_flash#concurrency-constraints-for-flash-on-spi1 ...
by szguyer
Mon Jan 13, 2020 8:44 pm
Forum: ESP-IDF
Topic: Impact of concurrency constraints in SPI Flash interface
Replies: 5
Views: 7101

Impact of concurrency constraints in SPI Flash interface

Hello all, I am trying to track down some issues in the FastLED support for ESP32, particularly when combined with SPIFFS (for loading web interface stuff and storing animation patterns). We have had a number of reports that our driver (which uses the RMT peripheral to push bits out to the LED strip...
by szguyer
Wed Dec 25, 2019 4:04 am
Forum: ESP-IDF
Topic: questions about mutex and critical sections
Replies: 4
Views: 7071

Re: questions about mutex and critical sections

If it was declared static it would work (although that is not the case in the example).