PCH Program Execution Order

[Triton1020]

Hello,

I am new to this forum and to PIC programming. I have wrote a simple piece of code to enter a character into digit one of an LCD. The problem is, when I begin to modify the code by adding statements or by eliminating an unecessary function call, the program doesn't work any more. I have noticed that if I single step through the code, the "working" version steps through correctly and the "non-working" version jumps to the middle of the program and does not initialize properly. I have attached code showing the simplest manifestation. The first program calls LCD_Init() from a second file, and the second non-functioning program simply sets up the LCD directly. I can also cause this by adding SWITCH statements or if/else statements. Any help would be greatly appreciated.

LCD_Driver file:
#include "LCD_Driver.h"
#include "LCD_Init.c"
#define Digit_1_MSB COM0+0,COM1+0,COM2+0,COM3+3,COM2+3,COM1+3,COM1+2,COM0+2
#define Digit_1_LSB COM0+1,COM1+1,COM2+1,COM2+2,COM3+2,COM3+1,COM3+0

void main()
{

LCD_Init();
setup_adc_ports(NO_ANALOGS);
setup_adc(ADC_OFF);
setup_wdt(WDT_OFF);
setup_timer_0(RTCC_INTERNAL);
setup_timer_1(T1_DISABLED);
setup_timer_2(T2_DISABLED,0,1);
setup_timer_3(T3_DISABLED|T3_DIV_BY_1);
setup_comparator(NC_NC_NC_NC);
setup_vref(FALSE);

LCD_Symbol(0xEE, Digit_1_MSB);
LCD_Symbol(0x20, Digit_1_LSB);

}

LCD_Init file:
void LCD_Init(void)
{
setup_lcd(lcd_mux14,0);
return;
}

LCD_DRIVER (non-functioning)
void main()
{

setup_lcd(lcd_mux14,0);
setup_adc_ports(NO_ANALOGS);
setup_adc(ADC_OFF);
setup_wdt(WDT_OFF);
setup_timer_0(RTCC_INTERNAL);
setup_timer_1(T1_DISABLED);
setup_timer_2(T2_DISABLED,0,1);
setup_timer_3(T3_DISABLED|T3_DIV_BY_1);
setup_comparator(NC_NC_NC_NC);
setup_vref(FALSE);

LCD_Symbol(0xEE, Digit_1_MSB);
LCD_Symbol(0x20, Digit_1_LSB);

}
_________________
Regards,

John

[PCM programmer]

1. What PIC are you using ?

2. Post your #fuses statement.

3. Post your compiler version. This will be a number such as 3.191
or 3.235, etc., and can be found at the start of the .LST file in your
project folder.

These things may show me the problem (or a problem).

But you've got several little weird things in your program.
1. You're letting the program fall off the end of main()
where it will hit the hidden SLEEP instruction which is
placed there by CCS.
2. You've got a "return" statement at the end of a routine
which has no return value. But the routine will automatically
return. No "return" statement is required.
Those might be small things but to me they set off a red flag
that you've got other stuff in your program (not posted) that
may be causing problems.

[Triton1020]

Thanks for the patience. As you have gleened, I am an inexperienced programmer. I appreciate the tips. The info you requested:

1. PIC18F8490
2. #include <18F8490.h>
#device adc=8
#use delay(clock=8000000)
#fuses NOWDT,WDT128,NOPROTECT, BROWNOUT, BORV21, NOPUT, IESO, STVREN, NODEBUG, FCMEN, MCLR, LPT1OSC, XINST
3. PCH Version 3.235

I am using the PIC18F8490 LCD Demo board for testing.

[PCM programmer]

1. I don't see an oscillator setting in your #fuses statement, such as
HS or INTRC_IO. You should add one.

2. Normally, the #use delay() statement is placed after the #fuses
statement. If you use INTRC or INTRC_IO, and you place the
#use delay() statement after the #fuses statement, the compiler
will automatically insert code to setup the internal oscillator for the
specified frequency. Example:

#fuses INTRC_IO // Other fuses not shown
#use delay(clock=8000000)

3. Change the XINST fuse to NOXINST. See the last post in this thread:
http://www.ccsinfo.com/forum/viewtopic.php?t=21251&highlight=xinst

[Triton1020]

That seems to have fixed the execution order if I single step. However, when I reach the "setup_lcd" function in the non-functioning code, it doesn't initialize the LCD. If I try and add a SWITCH or an IF statement, I am back to the execution order being all messed up.

A couple of things to note:
- When I use the wizard, it sets up PSP_Disabled, but the compiler does not recognize this function.
- If I try to use the INTRC fuse, the compiler does not recognize this either.
_________________
Regards,

John

[PCM programmer]

[Triton1020]

I just copied your program into a new file and got the compiler error:
Unknown keyword in #FUSES "0x08". If I change the fuse to INTRC_IO, it compiles fine.

I believe the computer that I am using had an old version compiler for a PIC 16. I purchased the latest PCH to allow PIC18 capability. I wonder if the 2 programs are interacting? I'll try removing everything and reloading.
_________________
Regards,

John

[PCM programmer]

Right. You can't mix versions of the PCM and PCH. The last one
that is installed is the one that works. You might be able to get
away with not re-installing each one before you use it, if the version
numbers are close and if CCS didn't change Devices.dat too much
between the versions.

Here is what Darren had to say on the topic:

[Mark]

[Triton1020]

That was it! I unistalled the old version and reinstalled PCH w/updates and everything works as expected. Of course, now I can't use the editor which kind of stinks, but I can live with that.

Thank you very much for your help.
_________________
Regards,

John

[adrian]