Demystifying LCD Pinouts

Recently I bought a couple of LCDs from China. The LCDs were listed as 1.8" SPI TFT LCD and the specified resolution was 128x160.

Once receiving LCDs I realized that the pinout printed on silkscreen had:

  • SCK
  • SDA
  • A0

This got me confused because A0 and SDA are I2C standard terms but SCK is SPI term?

Engineering (Reverse):

Here is my attempt to reverse engineer the two LCDs:

After some some reverse engineering on two different types of modules and going through the LCD datasheet I realized that the connections map as below:

LCD   -   Bus / Meaning
Vcc   -   Vcc
Gnd   -   Gnd
CS    -   CS (Chip Select)
Reset -   Reset (Module Reset)
A0    -   D/C (Data / Command)
SDA   -   MOSI (Master Out Slave In) SPI
SCK   -   SCK  (Serial Clock) SPI
LED   -   LED Backlight +V (~3v - use a current limit resistor)

I tested one of the LCD using an Arduino compatible system and it worked fine. The other one still needs to be tested. I may have destroyed my modules during RE so take care when you go on a similar quest.

Bottom line:

Do not hesitate to buy cheaper modules from China based manufacturers. All you need to do is some research and development. Please share your findings.