Save your .hex files on SDcard, select one in menu with the buttons Up and Down, then press Ok to program the controller.
Supported controllers for program: Atmega 328p
For reboot programmer send reboot from controller.
For load another file send load:filename.hex
Programmer <-> Controller
D3 --------- SCK
D5 --------- Reset
D6 --------- MISO
D7 --------- MOSI
Programmer <-> SD
D4 ------- CS
D11 ------- MOSI
D12 ------- MISO
D13 ------- SCK
Programmer <- Buttons
A0 -------- Up
A1 -------- Down
A2 -------- Ok
D8 -------- Cancel
Projects: Simple OLED game console: https://easyeda.com/Forem/multi