18F2520 Oscillator settings - Electronic Circuits Projects Diagrams Free

superbrew · 11th March 2008, 02:15 AM

Hello, I am trying to use an 18F2520 with a GLCD and it seems to be running really slow. The GLCD fill command takes about 5-7 seconds to finish. Here is the code that I am using with the mikroC compliler.

Code:

void main()
{
     TRISA = 0xff;
     TRISB = 0x00;
     TRISC = 0x00;
     PORTB = 0x00;
     PORTC = 0x00;
     ADCON1 = 0x0f;
     OSCCON = 0x07;
     OSCTUNE = 0x40;
     
     Glcd_Init(&PORTC,1,0,2,4,6,5,&PORTB);
     Glcd_Fill(0);
     Glcd_Set_Font(FontSystem5x8, 5, 8, 32);
     Glcd_Write_Text("TEST",0,0,1);
}

I am also using the default project fuses. Thanks

blueroomelectronics · 11th March 2008, 02:29 AM

What crystal are you using?

Pommie · 11th March 2008, 02:37 AM

Doing OSCCON = 0x07 selects the internal oscillator at 32kHz. Try OSCCON = 0x72 for the internal 8MHz clock or OSCCON = 0x00 if you have an external crystal. If you have an external crystal then you may have to set the fuses appropriately.

Mike.

superbrew · 11th March 2008, 02:49 AM

Unbelievable!

The OSCCON was supposed to be set to 0x70, not 0x07. Thanks so much for noticing that.

It works perfectly now, thanks.

Pommie · 11th March 2008, 03:06 AM

It's amazing how often the error is a simple typo but almost impossible to spot without a fresh set of eyes.

Mike.

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11th March 2008, 02:15 AM	(permalink)
superbrew	18F2520 Oscillator settings Hello, I am trying to use an 18F2520 with a GLCD and it seems to be running really slow. The GLCD fill command takes about 5-7 seconds to finish. Here is the code that I am using with the mikroC compliler. Code: void main() { TRISA = 0xff; TRISB = 0x00; TRISC = 0x00; PORTB = 0x00; PORTC = 0x00; ADCON1 = 0x0f; OSCCON = 0x07; OSCTUNE = 0x40; Glcd_Init(&PORTC,1,0,2,4,6,5,&PORTB); Glcd_Fill(0); Glcd_Set_Font(FontSystem5x8, 5, 8, 32); Glcd_Write_Text("TEST",0,0,1); } I am also using the default project fuses. Thanks

11th March 2008, 02:29 AM	(permalink)
blueroomelectronics	What crystal are you using? __________________ Bill Smart Kits build Smart People http://www.blueroomelectronics.com

11th March 2008, 02:37 AM	(permalink)
Pommie	Doing OSCCON = 0x07 selects the internal oscillator at 32kHz. Try OSCCON = 0x72 for the internal 8MHz clock or OSCCON = 0x00 if you have an external crystal. If you have an external crystal then you may have to set the fuses appropriately. Mike.

11th March 2008, 02:49 AM	(permalink)
superbrew	Unbelievable! The OSCCON was supposed to be set to 0x70, not 0x07. Thanks so much for noticing that. It works perfectly now, thanks.

11th March 2008, 03:06 AM	(permalink)
Pommie	It's amazing how often the error is a simple typo but almost impossible to spot without a fresh set of eyes. Mike.