DIP switch select delay

[BrianT]

Some are dark brown. Some even have writing on them - I wonder what this one is?

Another clueless student trying to fudge a class project by the looks of it.

[mongater]

Yes it's 16F88 .. and it's 18pin... BLACK in color comes with some wording on top of it!! but I use my finger's to rub it off anyway.. and now it's unknown chips , so I put DIL18

Thanks mat janssen , this is what I've done first... I'm sure somewhere must have coded wrongly.. I'll check tonite again!

Thanks!

[Bruce]

Something like this is where LOOKUP2 comes in handy.

    @ DEVICE PIC16F88, WDT_OFF,INTRC_OSC,MCLR_OFF,BOD_ON,LVP_OFF,PWRT_ON,PROTECT_OFF

    DEFINE  OSC 8
    DEFINE  NO_CLRWDT 1
    OSCCON  = %01110000 ' 8MHz
    CMCON   = 7	        ' disable analog comparators
    ANSEL   = 0         ' disable A/D module, all digital
    X VAR WORD
    Index VAR BYTE

    LED VAR PORTB.0    
    TRISA = %00111100   ' RA2 to RA5 inputs for DIP switch
    PORTB   = 0
    TRISB   = %11111110 ' RB0 for LED
    OPTION_REG = %11111111
    
    WHILE OSCCON.2 = 0  ' wait for internal osc stable before moving on
    WEND
    
Main:
    Index = (PORTA >> 2) & $0F ' Read DIP switch AND mask result
    LOOKUP2 Index,[200,300,400,500,600,700,800,900,1000,2000,_
    3000,4000,5000,6000,7000,8000],X
    HIGH LED
    PAUSE X
    LOW LED
    PAUSE X
    GOTO Main

    END

Change the delay periods in the table to suite your app.

[mongater]

Thanks Bruce!

your code helps alot, and it looks much simpler then what I've done... thanks again!

[Archangel]

Hi Bruce,

 Index = (PORTA >> 2) & $0F ' Read DIP switch AND mask result

If I get this right . . translates to portA / 4 & %00001111 , what I do not get is what it means, are we doing math here to get a number ??? & = AND. What does it mean, Mask result?
I am really trying to get my head around how this works, because it works pretty sweet, Thanks

JS

[mister_e]

The OP show switch connected on RA<5:2>
>>2 : yes it's divide by 4... but also easier to figure out when you use the 'Shift it 2 positions to right' term. Here it will shift the whole PORTA reading, 2 bits to the right... hence remove PORTA<1:0>

the & $0F is indeed a Bitwise AND. This way it keep only bits <3:0>... here PORTA<5:2> once shifted to the right.

	                 76543210	
Index=                  %10101111
Index=Index >>2   ' now %00101011
Index=Index & $0F ' now %00001011

[Archangel]

Thank You Mister_e,
I will have to think on this awhile, but I see it throws out the 2 LSB and then throws out the 4 MSB, seems odd, I just have to get my thick head around it. Would it be possible to use say PortB and use only 4 ports in BCD fashion while using the rest as outputs? Something like
Index = PORTB<3:0>?
Thanks
JS