Re: Undeclared identifiers in tdisp_lld.c
Posted: Mon May 20, 2013 9:19 pm
Hi Joel,
I did that - took the STM32f4 demo - no changes just amended the makefile for GFX, however I didn't get a sensible lcd output. It was a combination of garbled output and no response to the home or clear commands.
I changed the main.c around a bit to set up a pattern I could recognize and tried to watch the output. I am fortunate enough to have a pc based oscilloscope one of these http://www.bitscope.com/product/BS325/ which has a logic analyser function. I can see a fluctuating 'E' enable line (correct) but also the RS line has the same pattern with a variable delay (incorrect).
The RS line should only change when the output changes from command to data and back again.
This led me to wonder if part of the 'standard' demo was also outputing to the same GPIO port - hence my desire to trim out the bits of the demo I didn't need.
I have tried 3 different LCD's with the same result, what I really really need is something simple that works and from which I can build - if anyone has a working LCD demo I would be most grateful.
I do appreciate all help.
Chris
I did that - took the STM32f4 demo - no changes just amended the makefile for GFX, however I didn't get a sensible lcd output. It was a combination of garbled output and no response to the home or clear commands.
I changed the main.c around a bit to set up a pattern I could recognize and tried to watch the output. I am fortunate enough to have a pc based oscilloscope one of these http://www.bitscope.com/product/BS325/ which has a logic analyser function. I can see a fluctuating 'E' enable line (correct) but also the RS line has the same pattern with a variable delay (incorrect).
The RS line should only change when the output changes from command to data and back again.
This led me to wonder if part of the 'standard' demo was also outputing to the same GPIO port - hence my desire to trim out the bits of the demo I didn't need.
I have tried 3 different LCD's with the same result, what I really really need is something simple that works and from which I can build - if anyone has a working LCD demo I would be most grateful.
I do appreciate all help.
Chris