Printable View
Char. LCD and 18F452 on 4 MHz working, but on 20 MHz not work.
Please help me.
Code:
define LCD_BITS 4
DEFINE LCD_DREG PORTD
DEFINE LCD_DBIT 4
DEFINE LCD_RSREG PORTC
DEFINE LCD_RSBIT 6
DEFINE LCD_EREG PORTC
DEFINE LCD_EBIT 7
DEFINE LCD_LINES 4
DEFINE LCD_COMMANDUS 2000
DEFINE LCD_DATAUS 50
LCDOUT $FE,1,"HELLO WORLD"
Did you tell PBP that you are using 20 mhz
DEFINE OSC 20
Yes mackrackit.Quote:
Originally Posted by mackrackit
And OSC = HS
But PBP not compile 18f452 to hex, MPASM compiling to hex. And MPASM compiling on (default) 4 MHz only.
MPASM is required for 18s.Quote:
Originally Posted by samettin
How do you know it is doing 4 MHz? Did you change the congig (*.inc) to HS?
I m sorry, i changed my message :)
I did change OSC to HS.
LCD vorking with 18F452 on 4 MHz xtal and osc config = XT.
Problem is, if PLL enable with 4 MHz XTAL, or 20 MHz with osc config=HS then.
Could you post all of the code and config, not what you think the configs are set for, but a copy paste of the *.inc.
Might want to also keep in mind that the PLL doesn't work above 10Mhz. The max speed of the PIC is 40Mhz (10 x 4xPLL). Try as you might, you won't get the PIC to run at 160Mhz! (It would be nice, but it won't work :) )Quote:
Originally Posted by samettin
My english is bad, sorry :D
With this code problem is finish. :)
Xtal = 20 MHz
Osc Config = HS
Need first code:
after initialising lcd:Code:pause 1000
LCDOUT $FE,1
pause 500
But PAUSE and PAUSEUS working at value/5.Code:LCDOUT $FE,1,"HELLO WORLD"
Example:
working to 1 Second.Code:PAUSE 5000
I edited in "pbppic18.lib" also PAUSE problem is finish.
with 4 MHz xtal pauseus macro.
Thanks for your interesting.Code:;****************************************************************
;* PAUSEUS : Pause n microseconds at 4MHz *
;* *
;* Input : R0 + 1, W = microseconds *
;* Output : None *
;* *
;* Notes : minimum 19us *
;****************************************************************
if (OSC == 4)
LIST
PAUSEUS clrf R0 + 1 ; 1
PAUSEUSL addlw -23 ; 1 Subtract overhead
movwf R0 ; 1
movlw -4 ; ********changed -1 to -4***********
bnc pauseush ; 1 / 2
nop ; 1
pauseusloop CLRWDT?NOP ; 1
addwf R0, F ; 1
bc pauseusloop ; 1 / 2
nop ; 1
pauseush addwf R0, F ; 1
decf R0 + 1, F ; 1
bc pauseusloop ; 1 / 2
btfsc R0, 0 ; 1 / 2
bra $ + 2 ; 2 / 0
btfss R0, 1 ; 1 / 2
bra pauseusdone ; 2 / 0
bra $ + 2 ; 0 / 2
nop ; 0 / 1
pauseusdone return ; 2 + 3 (call + setup)
NOLIST
endif
Best regards.
160Mhz?Quote:
Originally Posted by skimask
Sorry i dont see.
With 4 MHz and PLL 4X4 = 16 MHz.
20 MHz is without PLL. This osc conf. is XT.
Thought you said it was set for HS. XT will not work. Me thinks.Quote:
Originally Posted by samettin
It's good enough. Don't worry about it...Quote:
Originally Posted by samettin
Not understanding this statement.Quote:
With this code problem is finish. :)
Problem or No Problem?
Which leads me to believe that either you config statements are 'taking effect' or your PIC is actually running on the internal 4Mhz clock vs. the external 20Mhz oscillator.Quote:
But PAUSE and PAUSEUS working at value/5.
Example:
working to 1 Second.Code:PAUSE 5000
No problem :)Quote:
Originally Posted by skimask