635 text to screen problems


New member
Hi there...

I sometimes make multiple calls in a row to the lcd in order to print things to the screen. Occassionaly lines of text are missing. I've tried to remedy this situation by creating a semaphor around send_packet and adding a delay of 50 ms in there also before unlocking.

I know that it is recommended to wait for the packet to be acknowledged before sending the next one but is there anyway to avoid this or is there a guaranteed time delay to make it work 100% of the time?

The current semaphor/50ms set-up I have only created one missing line of text after observing 2 to 3 hours of text swapping on the LCD, but since this will be sold to a consumer, it should be a requirement for this to work.

So should i wait for the ack or is there still a quick method around this using delays?

Thanks for the help!
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CF Tech

Officially you should wait for the ACK.

I would think that 50mS would be plenty of time for the the line to be displayed, but I have never timed the code.