PORTB vs PORTB.0

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- 3rd March 2007, 23:52
xzolian

PORTB vs PORTB.0

Can some one tell me why this code works

Code:

OSCCON = %01100010 ADCON1 = %01111111 TRISB = 0 loop: Pause 500 ' Wait .5 second PORTB.3 = 1 Pause 500 ' Wait .5 second PORTB.3 = 0 Goto loop END

And this code works as well ...

Code:

OSCCON = %01100010 ADCON1 = %01111111 TRISB = 0 loop: Pause 500 ' Wait .5 second PORTB = %11111111 Pause 500 ' Wait .5 second PORTB = %00000000 Goto loop END

But this code does not...

Code:

OSCCON = %01100010 ADCON1 = %01111111 TRISB = 0 loop: Pause 500 ' Wait .5 second PORTB = 1 Pause 500 ' Wait .5 second PORTB = 0 Goto loop END

I tried searching for the answer and I could not find anything. Maybe I don't know how to search properly.

Thanks in advance,
Matt

p.s. I'm using a pic18f1320 and programming it using the PICKIT 2
p.s.s. Sorry if this post is in the wrong forum
- 3rd March 2007, 23:59
mister_e

the second will toggle the PORTB.0 bit while the first toggle PORTB.3 bit. If you don't have LED on all PORTB pins, the problem is as this simple.

Or once again i miss something obvious :D
- 4th March 2007, 00:09
xzolian

I have placed an LED on pin 3 of port b. When I used these statements:
PORTB.3 = 1 or PORTB = %11111111
The LED on pin 3 of port b turns on.

But when I use this statement:
PORTB = 1
The LED does not turn on.

How can I set all of port b high or low with one statement?
- 4th March 2007, 00:10
Ron Marcus

PORTB = 1 = %00000001
PORTB = 0 = %00000000
Each bit equals a port pin. You are changing PORTB.0 only. If you wanted to change only bit 3, then it would be PORTB = %00001000
- 4th March 2007, 00:19
keithdoxey

Quote:

Originally Posted by Ron Marcus

PORTB = 1 = %00000001
PORTB = 0 = %00000000
Each bit equals a port pin. You are changing PORTB.0 only. If you wanted to change only bit 3, then it would be PORTB = %00001000

Or PORTB = 8
- 4th March 2007, 00:22
xzolian

So if I do this...
PORTB = 255

Would it set all of PORTB high?
- 4th March 2007, 00:22
mister_e

Yes indeed!

PORTB=255 ' decimal
PORTB=$FF 'Hexadecimal
PORTB=%11111111 ' Binary

P.S.: it's a good practice to set your PIC configuration fuses in your code.

Code:

' ' Pic Configuration ' ================= asm __CONFIG _CONFIG1H, _IESO_ON_1H & _FSCM_OFF_1H & _INTIO2_OSC_1H ; ;_IESO_ON_1H Internal External Oscillator Switch Over mode enabled ;_FSCM_OFF_1H Fail-Safe Clock Monitor disabled ;_INTIO2_OSC_1H Internal RC, OSC1 as RA7, OSC2 as RA6 __CONFIG _CONFIG2L, _PWRT_ON_2L & _BOR_ON_2L & _BORV_27_2L ; ;_BORV_27_2L BOR Voltage - 2.7v ;_BOR_ON_2L Brown-out Reset enabled ;_PWRT_ON_2L Power-up Timer enabled __CONFIG _CONFIG2H, _WDT_OFF_2H & _WDTPS_32K_2H ; ;_WDT_OFF_2H Watch Dog Timer disabled ;_WDTPS_32K_2H 1:32,768 WDT Postscaler ratio __CONFIG _CONFIG3H, _MCLRE_ON_3H ; ;_MCLRE_ON_3H MCLR enabled, RA5 input disabled __CONFIG _CONFIG4L, _DEBUG_OFF_4L & _LVP_OFF_4L & _STVR_ON_4L ; ;_DEBUG_OFF_4L BacKground deBUGger disabled ;_LVP_OFF_4L Low Voltage Prgramming disabled ;_STVR_ON_4L Stack over/underflow Reset enabled __CONFIG _CONFIG5L, _CP0_OFF_5L & _CP1_OFF_5L __CONFIG _CONFIG5H, _CPB_OFF_5H & _CPD_OFF_5H __CONFIG _CONFIG6L, _WRT0_OFF_6L & _WRT1_OFF_6L __CONFIG _CONFIG6H, _WRTC_OFF_6H & _WRTB_OFF_6H & _WRTD_OFF_6H __CONFIG _CONFIG7L, _EBTR0_OFF_7L & _EBTR1_OFF_7L __CONFIG _CONFIG7H, _EBTRB_OFF_7H ENDASM

There's a whole thread about that bellow. Take your time to read it.
http://www.picbasic.co.uk/forum/showthread.php?t=543
- 4th March 2007, 00:33
xzolian

Thanks for the help everyone.