ILI9488 MISO Fault Question


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stanleyella

Guru

Joined: 25/06/2022
Location: United Kingdom
Posts: 2158
Posted: 07:39pm 02 Dec 2022      

  phil99 said  "It seems this display is annoying compared to ili9341 from all the ways to get it working so not just me"

I think you have got the wrong idea. That there are so many ways to overcome the issue shows that it is easy to fix.

Everyone finds that just adding one 680R resistor fixes touch and for most it also fixes SD access.

Get touch working first with the 680R and then test SD. If SD won't go or is unreliable try any of the other fixes. I have tested them all and they all work on my ILI9488.

Repeating what Peter just wrote, The ONLY thing connected to SDO (in your photo its SDO(MISO)) is the 680R. T_DO and SD_DO go directly to the Pico MISO pin GP16.



This is a simple way to eliminate the possibility of connection problems.


Ta again phil99.
I rewired as before ie 680R from lcd miso to touch t_do and sd_do and it is the same in that it appears to work fine. Touch calibrates and works fine, it reads a sd card and the graphics seem fine.
But then as before I found blit does not work. A test program that moved 16 sprites now moves 16 white squares until the screen is full.
I tried the diode resistor circuit with same results.
Just the p200 transistor circuit to try but I have none so I'll check if I got an equivalent.

If it was not for blit failing I would have thought the 680R in lcd miso a simple solution
and who uses blit on lcd anyway?