LPC MicrocontrollersのトピックLCD flickering on LPC1788

LCD flickering on LPC1788

lpcware — Wed, 15 Jun 2016 18:02:49 GMT

Content originally posted in LPCWare by reza_elc87 on Sun Jan 17 06:00:51 MST 2016
Dear all,

I am fairly new to the LCD controller of LPC1788.
I have a 7" (800*480) TFT LCD and I wan to drive it using the LPC1788 MCU. I am using the SWIM graphics library developed by NXP to build a user interface which includes buttons, Text boxes, labels, etc. The problem I am having is that when you click a button or do things of that kind and the LCD want to upload a new frame, it flickers. I have tried to use double buffering but it did not work out (maybe I am using it wrong).

If you have any experiences in this field (preventing flickering) or any code sample I would really appreciate if you helped me.

Re: LCD flickering on LPC1788

lpcware — Wed, 15 Jun 2016 18:02:50 GMT

Content originally posted in LPCWare by padmaja on Tue Jan 19 01:22:35 MST 2016
hi,
we are also using 7"(800x480)tft with LPC1788 but i can't access some pixels.If i tried to write those pixels data was written to SDRAM but that not effects on LCD. I don't know why it is like that. do you have any idea about this type of problems?

In each line, from 0 to 108 pixels it was responding ok after 108 to 300 pixels not responding (always it shows some vertical lines) that corresponding data. after 300 to 800 pixels then again ok

thanks & regards,
padmaja.

Re: LCD flickering on LPC1788

lpcware — Wed, 15 Jun 2016 18:02:58 GMT

Content originally posted in LPCWare by padmaja on Tue Jan 19 01:51:06 MST 2016
hi,

i found some settings in one post (https://www.lpcware.com/content/forum/emwin-mirrored-lcd-problem) i saw LCD settings of HSW,HFP,HBP,VSW,VFP,VBP. i just changed these settings with values contained in above link. My dislpay was working clean no vertical lines :) feeling happy. But May i know how to calculate these (HSW,HFP,HBP,VSW,VFP,VBP). Is these setttings mentioned in LCD datasheet? i didn't find anywhere. But display was working with above mentioned link contained settings. Anyways very usefull information this forum contains.
thanks to Nxp. thank u all

regards,
padmaja.

Re: LCD flickering on LPC1788

lpcware — Wed, 15 Jun 2016 18:02:58 GMT

Content originally posted in LPCWare by mc on Tue Jan 19 10:55:00 MST 2016
Hi Padmaja,
All these values are coming form LCD datasheet. You need to set various registers in LCD controller according to LCD specification.

@reza,
Your double buffering may not be set correctly. Also, check the SDRAM speed in your project.

Re: LCD flickering on LPC1788

lpcware — Wed, 15 Jun 2016 18:03:04 GMT

Content originally posted in LPCWare by padmaja on Wed Jan 20 07:24:29 MST 2016
Hi mc,
I am using umsh-8596md-20t 7" lcd display in this they mentioned so.e timing parameters. But, i am unable to understand how eill get hsw,vse,etc from these values.
Is there any way to get these things?

Thanks & regards,
Padmaja.