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SOLVED: Problem sending character to LCD via UART/Serial
Posted: Wed Dec 02, 2015 6:09 am
by bvolken
Target: PIC18F4580
Programmer: PICKIT3
OS: Windows 10 home 64 bit
FlowCode 6.1.2.0 (11.05.2015)
Send a 0x41 to the screen and it puts an "A" exactly as expected.
Send a member of the string array, and display prints junk
Tracing variable as passed to the serial send routine, it looks exactly as I would expect.
Re: Problem sending character to LCD via UART/Serial
Posted: Wed Dec 02, 2015 10:40 am
by LeighM
I would suspect an issue with the serial connection and check the accuracy of the baud rate (if you can)
Re: Problem sending character to LCD via UART/Serial
Posted: Wed Dec 02, 2015 11:42 am
by Benj
The one second flash test is a great way to sanity check your clock speed and settings are right.
http://www.matrixtsl.com/wiki/index.php ... ED_flasher
Once your clock speed and settings are correct the baud rate should also be correct.
Re: Problem sending character to LCD via UART/Serial
Posted: Wed Dec 02, 2015 4:23 pm
by bvolken
I know the clock and baud are right. I have run lots of tests. The only change is now trying to send a string (array) one byte-at-a-time.
When I pass "0x41" an "A" is displayed (confirming baud is right), but passing StringVar[4] does not work, even though it appears to pass a valid ASCII code to the print macro.
The CAL_UART is expecting a UINT parameter, and I am passing it a BYTE, which works when I pass "0x41", could this be related to the issue. I couldn't find much on variable typecasting.
Re: Problem sending character to LCD via UART/Serial
Posted: Wed Dec 02, 2015 4:39 pm
by Benj
Can you attach your program so we can see what might be going wrong.
Re: Problem sending character to LCD via UART/Serial
Posted: Wed Dec 02, 2015 10:56 pm
by bvolken
Here you go. I can't help but feel it's got something to do with variable typecasting, but since it's only my 3rd day with Flowcode . . . who knows!?!
Should I download and apply "Flowcode 6 - latest components, bug fixes and improvements"?
Re: Problem sending character to LCD via UART/Serial
Posted: Thu Dec 03, 2015 10:21 am
by LeighM
Hi,
Looking at the generated casm file, it looks like the typecasting is OK, despite it being logical to suspect it, and your code is very good for 3 days with Flowcode!
Have you tried?...
LCD_PrintChar('H')
LCD_PrintChar('e')
LCD_PrintChar('l')
LCD_PrintChar('l')
LCD_PrintChar('o')
I'm just fishing for more clues here.
As you say, updating to the latest is always a good idea
Re: Problem sending character to LCD via UART/Serial
Posted: Thu Dec 03, 2015 10:43 am
by Benj
Hello,
In your config settings switch of the extended CPU setting. This is known to cause corruption with arrays. Then your program should hopefully work as expected.
Re: SOLVED: Problem sending character to LCD via UART/Serial
Posted: Fri Dec 04, 2015 7:26 pm
by bvolken
Okay, turns out the problem was indeed the "Extended CPU Enable"
- UART1.jpg (86.92 KiB) Viewed 5683 times
After switching to "disabled", the code worked as expected.
THANKS FOR THE SUGGESTION! 