part of [Linas]’ submission to last year’s Cypress Smarter Life challenge involved using the HTC desire display and its touch screen. This particular phone includes a full-color active-matrix OLED (AMOLED) display that has a 3.7″ diagonal and a 480×800 resolution, resulting in a 252ppi pixel density. using a MSO2024B oscilloscope, [Linas] originally started his adventure with the touchscreen by sniffing the I2C signals. As some math was needed to extract the data, he later found the HTC desire source code and included it on his STM32F429 (so much for reverse engineering!).
After spending lots of hours searching for the AMOLED display and controller datasheets, [Linas] resorted to pay a company to get the resources he needed. He produced a tailor-made PCB to supply the display with the needed voltages, as well as offering a 0.1″ connector to interface with it. A RGB565 interface is used to communicate with the screen so only 65k out of the 16 million colors are used. You may download all the program data and datasheets in [Linas] write-up.