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PCM programmer
Joined: 06 Sep 2003
Posts: 21708
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 Posted: Sat Aug 20, 2011 6:01 pm |
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| Quote: | int8 milliseconds = 0;
if(milliseconds == 1000) |
What's wrong here ? Data types, data types, data types.
Download the CCS manual:
http://www.ccsinfo.com/downloads/ccs_c_manual.pdf
Look on page 43 (page 57 in the Acrobat reader). Look at this section:
| Quote: | Basic and Special types
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Note the range of each data type. |
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Wilksey
Joined: 14 Aug 2011
Posts: 36
Location: Somerset, UK
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| Posted: Sat Aug 20, 2011 6:40 pm |
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Hmmm...I see what you're saying...i'm an idiot!!
So, I changed it to int16, and it still isn't giving me quite what I need.
The timer2 code still doesn't work, in fact it doesn't appear to fire at all!
If I remove the RTCC_8_BIT from timer0 code, I have to set RTCC_DIV_1 to get a 4/5 ms delay, but can't seem to acheive 1ms still.
Wilksey |
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Ttelmah
Joined: 11 Mar 2010
Posts: 19233
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| Posted: Sun Aug 21, 2011 2:27 am |
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One thing I notice, you have the comment 'Master Clear pin used for I/O', but have the fuse 'MCLR' which means the master clear pin is enabled, and you must have a pull-up on the master clear pin.
I'd add:
setup_oscillator(OSC_64MHz);
as the first line of the main code. Some compiler versions don't turn the software PLL on, without this.
Don't enable the interrupts, until you have set them up. Won't matter really (just risks an extra trigger), but 'bad practice'.
One thing I notice, is you don't have the NOPBADEN fuse, which means port B will wake up as analog by default.
I rewrote the code to generate a 5 second time using a 1mSec tick on Timer2, as:
| Code: |
#include <18F25K22.h>
#FUSES NOWDT, WDT128, INTRC_IO, NOFCMEN, NOIESO, BORV42, WDT_NOSLEEP, NOPBADEN, NOLPT1OSC, NOHFOFST, NOMCLR, NOLVP, NOXINST
#use delay(clock=64000000)
#use rs232(baud=9600,parity=N,xmit=PIN_C6,rcv=PIN_C7,bits=8,stream=PORT1,errors)
int16 milliseconds=5000;
#int_timer2
void tick(void) {
if (milliseconds) --milliseconds;
}
void main()
{
setup_oscillator(OSC_64MHZ);
setup_timer_4(T4_DISABLED,0,1);
setup_comparator(NC_NC_NC_NC);
setup_timer_2(T2_DIV_BY_16,99,10);
enable_interrupts(INT_TIMER2);
enable_interrupts(GLOBAL);
do {
if (milliseconds==0) {
milliseconds=5000;
printf("5 seconds\n\r");
}
} while(TRUE);
}
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and it merrily displays '5 seconds' on the serial, every 5 seconds exactly.
Using the 'countdown', makes it impossible for the value to be missed if the main loop takes too long (doesn't apply here).
Best Wishes |
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Wilksey
Joined: 14 Aug 2011
Posts: 36
Location: Somerset, UK
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| Posted: Sun Aug 21, 2011 5:07 pm |
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Hi Ttelmah,
Thank you for your reply, I will check your code and see what it does on my board.
Can the code count up instead of down?
I tried adding the setup_oscillator to 64MHZ, but doesn't make any difference, both UARTS i have tried work fine, so im guessing the crystal setting is ok as if it wasn't i'd get garbage.
MCLR is pulled to +5V with a 10k pull up.
I dont think portb pullups are an issue, but I will add that fuse setting in for good practice!
Although, doesn't this override it?
| Code: |
setup_adc(ADC_OFF | NO_ANALOGS);
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Wilksey |
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Wilksey
Joined: 14 Aug 2011
Posts: 36
Location: Somerset, UK
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| Posted: Sun Aug 21, 2011 6:08 pm |
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Hi,
Just tried your code, changed the header to the 26K22, had to remove one of the fuses, cause it didn't exist on my chip, it just sits there and does nothing, I have tested the UART and it works ok, but your code just sits and does nothing?
Wilksey |
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Ttelmah
Joined: 11 Mar 2010
Posts: 19233
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| Posted: Mon Aug 22, 2011 1:47 am |
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What compiler version have you got?.
The fuses should be right. The 25K, and the 26K are identical, except the 26K has more memory. The code ran exactly as it is on a 25K, and compiles with no changes at all to run on a 26K. I wonder if you have an early compiler for the 26K, which has problems setting the chip up....
Best Wishes |
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Wilksey
Joined: 14 Aug 2011
Posts: 36
Location: Somerset, UK
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| Posted: Mon Aug 22, 2011 10:08 am |
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It was this fuse that caused errors:
NOLPT1OSC
I use 4.120
Thanks
Wilksey |
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PCM programmer
Joined: 06 Sep 2003
Posts: 21708
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| Posted: Mon Aug 22, 2011 1:47 pm |
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I was able to make Ttelmah's code work with vs. 4.120 with the following
changes (in various places below). This is the program output:
| Quote: |
Start:
5 seconds
5 seconds
5 seconds
5 seconds
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Here is the test program:
| Code: |
#include <18F45K22.h>
#FUSES INTRC_IO, NOWDT, BROWNOUT, PUT, NOPBADEN, NOHFOFST
#use delay(clock=64M)
#use rs232(baud=9600, UART1, ERRORS)
#byte OSCCON2 = getenv("SFR:OSCCON2")
#bit PLLRDY = OSCCON2.7
int16 milliseconds=5000;
#int_timer2
void tick(void)
{
if(milliseconds)
--milliseconds;
}
//=========================
void main()
{
while(!PLLRDY); // Wait until 64 MHz osc is running OK
printf("\n\rStart: \n\r");
setup_timer_2(T2_DIV_BY_16,99,10);
enable_interrupts(INT_TIMER2);
enable_interrupts(GLOBAL);
do{
if(milliseconds==0)
{
milliseconds=5000;
printf("5 seconds\n\r");
}
}while(TRUE);
}
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Note that testing the PLLRDY bit at the start of main() was the only way
I could get the program to display "Start" correctly at the beginning
of the program. I tried other methods and they didn't work. |
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Wilksey
Joined: 14 Aug 2011
Posts: 36
Location: Somerset, UK
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| Posted: Mon Aug 22, 2011 4:00 pm |
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Thanks PCM
I will try that code on my board tomorrow!
Thanks to both of you for all of your patience and help so far!!
Wilksey |
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