• We recently switched our forum platform. If you experience any issues please email support@crystalfontz.com

Best LC/R for CFAG320240 to reduce flicker

makku

New member
Hi, I'm fine tuning the display and I still get a tiny bit of flicker when it's updating pixels on the LCD. My processor sends out instructions at 4us intervals so it's not the write speed (I think). I'm thinking it's the LC/R setting. In the docs for the SED1335, there's an equation to calculate the correct LC/R based on crystal frequencies but I can't find any mention of what you guys use for this board. What is the best LC/R to use? I've seen two different numbers in sample code you've sent me and neither seems to be flicker free... any ideas?
Looking for additional LCD resources? Check out our LCD blog for the latest developments in LCD technology.
 
The best solution is to spend a few bytes of code to check the status flag, to synchronize your updates, then the LCD frequency is irrelevant.
 

makku

New member
hmm... i've thought about doing that but I don't know if I'll have spare i/o pins on my processor. I'm pretty sure that the time between my enable pulses and data pin updates are long enough that I wouldn't need to check the status flag. Am I thinking of the wrong thing though?

This processor isn't a PC... it's like a basic stamp or pic. Pretty slow... it takes around 2-4 us for each instruction and I think that's well within the timing needed to have the LCD controller update the screen. In any case, I've tried adding deliberate pauses and it doesn't help.

The data sheet for the SED1335 mentions the LC/R setting as a possible cause for flicker so I wanted to get that right first.
 
Top