Codec Services

HID Codec "cdc:HID"

Command Header	Description
0x00010000	GetData
0x00020000	Initialize
0x00030000	Finalize

Touchscreen

The touchscreen is the SPI device number 3, so it uses the 0x10142XXX SPI registers. It is initialized by issuing the following SPI commands:

spi_select_reg(3, 0x67);
spi_offset_mask(3, 0x26, 0x80, 0x80);
spi_select_reg(3, 0x67);
spi_offset_mask(3, 0x24, 0, 0x80);
spi_select_reg(3, 0x67);
spi_offset_mask(3, 0x25, 0x10, 0x3C);

Once the touchscreen is initialized, you can start polling touch data:

u8 raw_touchdata[0x40];
spi_select_reg(3, 0x67);
spi_read_offset(3, 0x26); //The return value of this is checked against "& 2"
spi_select_reg(3, 0xFB);
spi_read_offset_array(3, 1, raw_touchdata, 0x34);

This is the format of the touchdata report:

Offset	Width	Description
0x00	2*5	Five Touchscreen X Coordinates (big-endian MSB,LSB each. 12 bits number)
0x0A	2*5	Five Touchscreen Y Coordinates (big-endian MSB,LSB each. 12 bits number)
0x20	??	??

When the touchscreen is not touched, all the coordinates report 0xFFFF, and since touch coordinates have only 12 bits, you can check if the touchscreen is pressed by checking the 4th bit of the MSB. For example: pendown = !(raw_touchdata[0] & BIT(4))

MIC Codec "cdc:MIC"

Command Header	Description

CSN Codec "cdc:CSN"

Command Header	Description

DSP Codec "cdc:DSP"

Command Header	Description

Legacy Codec "cdc:LGY"

Command Header	Description

CHK Codec "cdc:CHK"

Command Header	Description