Make esp32 c3 devkits work...

[fumanchi]

I had an ESP32-C3 Super Mini development board lying around and wanted it to be the new brain of my IKEA panel.

Partitions

When i compiled the code after setting up the board to "esp32-c3-devkitm-1" (in a separate environment in my platformio.ini), I got the following error:

Building in release mode
Retrieving maximum program size .pio/build/esp32-c3/firmware.elf
Checking size .pio/build/esp32-c3/firmware.elf
Error: The program size (1310810 bytes) is greater than maximum allowed (1310720 bytes)
Advanced Memory Usage is available via "PlatformIO Home > Project Inspect"
*** [checkprogsize] Explicit exit, status 1
RAM: [= ] 14.0% (used 45788 bytes from 327680 bytes)
Flash: [==========] 100.0% (used 1310810 bytes from 1310720 bytes)

The C3 firmware resulted in a binary that no longer fit into the default partitions. To make it fit while still supporting OTA updates, I ended up with the following "platformio.ini":

nvs,      data, nvs,           ,  0x4000,
otadata,  data, ota,           ,  0x2000,
phy_init, data, phy,           ,  0x1000,
ota_0,    app,  ota_0,         ,  1200K,
ota_1,    app,  ota_1,         ,  1200K

Hint: I am not completely sure if this partition structure effects any other features, yet.

Another inconvenient Point is

PIN selection via constant.h

Since the C3 Super Mini has a limited number of pins, it would be great to select them in the platformio.ini environment (here: [env:esp32-c3]) by setting some build flags.

build_flags =
	-DPIN_ENABLE=3
	-DPIN_DATA=2
	-DPIN_CLOCK=1
	-DPIN_LATCH=0
	-DPIN_BUTTON=10

To avoid any impact from the current environments, I suggest the following changes to "constants.h":

#ifdef ESP32
#ifndef PIN_ENABLE
#define PIN_ENABLE 26
#endif
#ifndef PIN_DATA
#define PIN_DATA 27
#endif
#ifndef PIN_CLOCK
#define PIN_CLOCK 14
#endif
#ifndef PIN_LATCH
#define PIN_LATCH 12
#endif
#ifndef PIN_BUTTON
#define PIN_BUTTON 16
#endif
#endif

I would appreciate it if you could take these changes into account.

Best regards