The color TFT is what you're here for! This 0.96" diagonal display has surprisingly high resolution, 80x160 16-bit color pixels inside.
The display is in the middle of the Wing and uses 4 Wing pins and then 2 seesaw pins:
- SPI SCK - SPI data clock out from Feather to display
- SPI MOSI - SPI data transmit from Feather to display
- SPI CS - Chip Select pin, on the first digital pin to the left of SCL
- SPI DC - Data/Command select, on the second digital pin to the left of SCL
SCK and MOSI are fixed to the default SPI pins on each Feather. You can change the CS and DC pins if you'd like! On the bottom of the Wing there are solder jumpers, cut the default CS & DC and solder them to any two pins you like. We alternate so you have a few options.
The remaining two pins for controlling the TFT are handled by seesaw (our I2C converter chip):
- TFT Reset - we only need to toggle this pin once at the beginning of running a program, and it can happen slowly so we use seesaw to manage this pin
- TFT Backlight - not all Feathers have PWM and also most of the time you don't need to do a lot with the backlight so we connect it to a seesaw PWM pin so you can dim/brighten as you desire
In addition to a pretty display, now you have a little user interface you can build. You get 7 total buttons
- Button A
- Button B
- 5-way Navigation Joystick - Up/Down/Left/Right/Select
Since many GPIO would be needed for so many buttons we use seesaw on I2C to manage reading all the buttons.
seesaw is on I2C, it is a pre-programmed ATSAMD09 chip which will listen to commands over I2C and read buttons, dim the backlight and toggle the display reset line.
In addition, there is a reset button that will reset both Feather and Wing, and to power the wing we connect to the GND/3.3V power pins supplied by the Feather power supply.