USBSERVICE and LCDOUT won't work together

Hi,

I am working on a touchscreen USB project where I need to see the value of some variables, so I am trying to display this data on a parallel LCD display using LCDOUT. When the LCDOUT runs the USB communication dies; otherwise, the program runs flawless. I am using 10 ms polling and a pic18f4550. I use USBSERVICE right before and after the LCDOUT command but still the USB communication dies.

Yes, I know I can display this data in my pc using VB, but I am not there yet. Does anybody knows how long LCDOUT takes to execute and why the USB connection gets disconnected?

Thank you,

Robert

It's hard to say what's taking so long.
Any LCD commands take the time set by LCD_COMMANDUS.
Each character takes LCD_DATAUS.
If they are set really high, it could take a long time on a 4-line display.

But whatever they are set at, this might help with keeping USB serviced...

USB_ASM_Service.pbp
http://www.picbasic.co.uk/forum/show...06&postcount=6
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Darrel,

I entered the following two lines at the beginning of my program and it worked. Thank you, you are always very helpfull.


' Set command delay time in us
DEFINE LCD_COMMANDUS 2000
' Set data delay time in us
DEFINE LCD_DATAUS 50

Robert

Great, that's good news.
Simple fix.

http://www.picbasic.co.uk/forum/images/icons/icon14.gif