The Arduino libraries the board package's core provides: SPI, Wire (I2C) and EEPROM, ported to WCH's chips. More...

Modules
	SPI
	The Arduino SPI API: SPI master on SPI1, the CH32X035's one SPI.

	Wire (I2C)
	The Arduino Wire API: I2C master (and slave) on I2C1.

	EEPROM
	The Arduino EEPROM API over the option-byte area, for the CH32V003.

Detailed Description

The Arduino libraries the board package's core provides: SPI, Wire (I2C) and EEPROM, ported to WCH's chips.

These are the standard Arduino APIs, so sketches and libraries written for other boards work unchanged. On the CHGame board, note:

SPI1 belongs to the panel and the SD card. CHGfx drives it directly with DMA; use the SPI class only for your own devices, and only between gfx_wait() and the next flush. The SPI class resets SPI1 and sets its own clock and mode, so hand SPI1 back to CHGfx afterwards with gfx_setSpiDiv(gfx_spiDiv()).
Wire (I2C) is on the expansion header: SDA PC18, SCL PC19, with no pull-ups on the board.
Saving a game is done with the save:: functions of the CHGame library, which keep a record in flash with a CRC and survive re-uploads. EEPROM is the CH32V003's: on this chip its commit() writes nothing and returns false (rewriting the option bytes its way could leave the chip read-protected), and including it prints a compiler message.

Modules