2.8" 18-bit color TFT LCD with touchscreen

29 Mar 2012

I just bought a 2.8" 18-bit color TFT LCD with touchscreen from adafruit https://www.adafruit.com/products/335

Is there anything out there to get me started on controlling this with an mbed. There's a bunch of arduino literature out there but I haven't seen anything for mbed yet.

Thanks.

29 Mar 2012

The LCD use the ILI9325 controler. You have to use 8 bit parallel data + control.

You can look on my SPI TFT lib - http://mbed.org/users/dreschpe/libraries/SPI_TFT/m369bx to have a start point.

You have to change the low level code to suppot the ILI9325.

The LCD TFT lib - http://mbed.org/users/Suky/programs/LCDTFT_Library/llv383 also use a parallel display, but also a different controler.

30 Mar 2012

Thanks. Could you possibly go into more detail on what I would have to change in the low level code to support the ILI9325 controller?

30 Mar 2012

You have to change the code in SPI_TFT which access to the LCD controller. First you need a new wr_reg and rd_reg. You have to use 8 bit data + the control lines to read and write to the ILI9325 registers. The next step is to rewrite the tft_reset(). The power and display control rgister has to setup in the right order. You have to look into the arduino code to get the values. After setup you will see colored pixel. Most controllers don't erase the memory on power up. The next step is the window function. This function define a area between x1/y1 and x2/y2 were the pixel data is written. After that you have to change the pixel and the cls function. You can use the pixel function to do the rest, but most of my functions are more or less speed optimzed and use direct register access instadt of calling the pixel function.

Most register have to set only at reset. After that you allways define a area with the window function and put pixel into. A lot of register are similar but with different address. R22 start writing to the display ram in both controllers. The window register are R50-R53 in place of R2-R5. If you compare the datasheet of the HX8347 and the ILI9325 you will see the differences. The function is similar.

Peter

17 Jun 2012

Christian Valenti wrote:

I just bought a 2.8" 18-bit color TFT LCD with touchscreen from adafruit https://www.adafruit.com/products/335

Is there anything out there to get me started on controlling this with an mbed. There's a bunch of arduino literature out there but I haven't seen anything for mbed yet.

Thanks.

I bought the same display. I'm in over my head. Not sure where to start. I have looked at the code and have gone back and forth trying to figure out what to do. Pretty complicated for a noob. Did you ever get it working?