Jaycar MP3735 MPPT solar charge controller
The board ID reads:
The stickers read:
Searching for similar keeps bringing up the ProVista Maxi ISC 30. Same plastics but a different colour trim. There’s a model range but no mention of monitoring on any.
The CON2 header reads:
SDA SCL XRES G 5V
The CON1 header reads something like:
PCLK P??? GND 5V --
CON2 is probably I2C. There’s a periodic packet of data clocked at around 82 kHz.
Everything is 5 V which makes hooking it to my favourite 3.3 V STM32 tricky.