Search found 17 matches
- Fri Sep 03, 2021 10:50 pm
- Forum: Hardware
- Topic: SDMMC reads fail in 4-bit (but not writes)
- Replies: 0
- Views: 2196
SDMMC reads fail in 4-bit (but not writes)
I've got a SparkFun ESP32 Thing (1st gen) on a breadboard wired up to a microSD card using 4-bit SDMMC. It's connected to channel 1: GPIOs 15, 14, 2, 4, 12, 13 connect to CMD, CLK, D0, D1, D2, D3 respectively (with external pull-ups.) I'm using a brand new Samsung 256GB card. It works fine as long a...
- Mon Aug 30, 2021 7:30 pm
- Forum: Hardware
- Topic: Conflict between GPIOs used by bootloader vs. SDMMC
- Replies: 2
- Views: 3014
Conflict between GPIOs used by bootloader vs. SDMMC
I've got a SparkFun ESP32 Thing (1st gen) on a breadboard wired up to a microSD card using 4-bit SDMMC. The wiring is as directed by comments in the IDF example: GPIOs 15, 14, 2, 4, 12, 13 connect to CMD, CLK, D0, D1, D2, D3 respectively. And I've added external 10K pullups to all but CLK, as per th...
- Thu Dec 17, 2020 1:56 am
- Forum: Documentation
- Topic: ESP32 instruction set or assembly (ASM) programming docs?
- Replies: 19
- Views: 63894
Re: ESP32 instruction set or assembly (ASM) programming docs?
in my experience not having publicly-available documents seem to mostly affect those hobbyists and very few professionals. There's a large middle ground between "professional" and "hobbyist", and a lot of important software is developed by people in that middle ground. An NDA requirement is a prett...
- Wed Sep 30, 2020 10:44 pm
- Forum: Documentation
- Topic: ESP32 instruction set or assembly (ASM) programming docs?
- Replies: 19
- Views: 63894
Re: ESP32 instruction set or assembly (ASM) programming docs?
You could write it in C, once it works save assembly code, edit, assmble it, make sure it still works I haven't looked — is there actually an assembler/disassembler in the toolchain? Of course, trying to learn a completely new instruction set by reading disassembly is not my idea of fun, or even my...
- Tue Sep 29, 2020 5:16 pm
- Forum: Documentation
- Topic: ESP32 instruction set or assembly (ASM) programming docs?
- Replies: 19
- Views: 63894
ESP32 instruction set or assembly (ASM) programming docs?
I'm looking for documentation of the ESP32 instruction set, for assembly language programming. I've found some old (2010) Xtensa ISA docs, but their designs are so configurable that it's not much use for a specific CPU. I've seen two threads from a few years ago asking about this, and replies from E...
- Fri Jul 06, 2018 11:05 pm
- Forum: General Discussion
- Topic: Any way to strip C/C++ locale stuff out of the binary?
- Replies: 5
- Views: 9442
Any way to strip C/C++ locale stuff out of the binary?
When I run "make size-files" (with CONFIG_OPTIMIZATION_LEVEL_RELEASE) I see that a lot of the top contributors to the binary size are related to C/C++ locale handling: Per-file contributions to ELF file: Object File DRAM .data & .bss IRAM Flash code & rodata Total ... locale-inst.o 0 144 0 25655 723...
- Tue Jul 03, 2018 11:31 pm
- Forum: General Discussion
- Topic: Caching issues with mmap'ed flash
- Replies: 6
- Views: 8790
- Fri Jun 29, 2018 9:14 pm
- Forum: General Discussion
- Topic: Can I view other tasks in gdb?
- Replies: 1
- Views: 4175
Re: Can I view other tasks in gdb?
Of course, right after asking I found a (partial) answer. I can configure the program to log a core-dump when it crashes, and then read that dump into gdb. Then I can use the `info thread` and `thread` commands to view and switch to different threads/tasks. It even shows what the parameters and loca...
- Fri Jun 29, 2018 8:43 pm
- Forum: General Discussion
- Topic: Can I view other tasks in gdb?
- Replies: 1
- Views: 4175
Can I view other tasks in gdb?
Debugging with the gdb stub is very useful. But I can only see the thread/task that crashed, not any others -- `info threads` only shows that thread. I'm trying to debug a problem where a thread is hung inside system code (`select`), and while I can easily make another task force an exception and dr...
- Thu Jun 28, 2018 10:36 pm
- Forum: General Discussion
- Topic: Caching issues with mmap'ed flash
- Replies: 6
- Views: 8790
Re: Caching issues with mmap'ed flash
Looking through the spi_flash sources I found calls to a Cache_Flush() function; this looked promising, so I added to my code just after calling esp_partition_write(). That appears to have fixed the problem.
Code: Select all
Cache_Flush(0); Cache_Flush(1);