Power Pins

• V+ / Vin - This is the power pin. To power the board, give it the same power as the logic level of your microcontroller - e.g. for a 3V microcontroller like a Feather M4, use 3V, or for a 5V microcontroller like Arduino, use 5V.
• 3V / 3Vo - This is the output from the onboard 3.3V regulator. If you have a need for a clean 3.3V output, you can use this! It can provide at least 100mA output.
• G / Gnd - This is common ground for power and logic.

SPI Pins

• SCK - this is the SPI Clock pin. Use 3-5V logic level.
• MOSI - this is the Serial Data In / Microcontroller Out Sensor In pin. It is used to send data from the microcontroller to the SD card and/or TFT. Use either a 3.3 or 5V logic level
• MISO - this is the Serial Data Out / Microcontroller In Sensor Out pin. It is used for the SD card. It isn't used for the TFT display which is write-only. It is 3.3V logic out (but can be read by 5V logic)
• TFTCS - this is the TFT Chip Select pin. Use either a 3.3 or 5V logic level

Other Pins

• RST - This is the TFT reset pin. Connect to ground to reset the TFT! It's best to have this pin controlled by the library so the display is reset cleanly, but you can also connect it to the microcontroller Reset pin, which works for most cases. There is an automatic-reset chip connected so it will reset on power-up. Use either a 3.3 or 5V logic level
• DC - This is the TFT SPI data or command selector pin. Use either a 3.3 or 5V logic level
• CC / SDCS - This is the SD card chip select pin, used if you want to read from the SD card. Use either a 3.3 or 5V logic level
• BL / Lite - This is the PWM input for the backlight control. It is by default pulled high (backlight on) you can PWM at any frequency or pull down to turn the backlight off. Use either a 3.3V or 5V logic level

micro SD Card Slot

• On the back of the board, towards the middle, is the micro SD card slot. You can use any micro SD card that supports SPI mode with one CS pin.

EYESPI Connector

At the top edge of the back of the display is the EYESPI connector. This 18-pin FPC connector allows you to connect EYESPI-compatible displays using an EYESPI cable, with no soldering or jumper wires needed. All of the pins broken out at the bottom of the display board are available through the EYESPI connector:

1. VIN (3 to 5V DC power)
2. Backlight (Use either a 3.3 or 5V logic level, PWM optional input)
3. Ground
4. SPI Clock (Use either a 3.3 or 5V logic level in)
5. SPI MOSI (Use either a 3.3 or 5V logic level Microcontroller Out, Screen/SD In)
6. SPI MISO (Use either a 3.3 or 5V logic level Microcontroller In, Screen/SD Out)
7. TFT Data/Command (Use either a 3.3 or 5V logic level in)
8. TFT Reset (optional either a 3.3 or 5V logic level in)
9. TFT SPI Chip Select (Use either a 3.3 or 5V logic level in)
10. SD Card SPI Chip Select (Use either a 3.3 or 5V logic level in)
11. Unused
12. Unused
13. Unused
14. Unused
15. Unused
16. Unused
17. Unused
18. Unused