Again ADC with 12F675 ...

[peterdeco1]

Hi Fratello. A while back I did the same basic thing you're doing. On an ADC pin I attached a 47K pullup resistor. Then a 22K resistor with pushbutton to ground, 10K with button to ground, 2.2K with button to ground and a 1K with button to ground. Here is the code. It works perfect for me.

ANSEL = 0 'all inputs digital
CMCON = 7 'comparators off
DEFINE OSCCAL_1K 1 ' Set OSCCAL for 1K device to accurize osc
TRISIO = %11111111 'SET I/O'S to all inputs for now
@ device pic12F675, INTRC_OSC_NOCLKOUT, wdt_on, BOD_ON,pwrt_on, mclr_off, protect_on
BUT VAR BYTE 'BUTTON VARIABLE
BUT2 VAR BYTE 'VARIABLE TO COMPARE READINGS TO PREVENT WRONG ADC READINGS
Pause 500 'SETTLE DOWN

STAYHERE:
ADCIN 3,BUT 'ADCIN COMMAND AUTOMATICALLY CONVERTS I/O TO ADC PORT
IF BUT < 100 Then STAYHERE 'IF BUTTON STUCK on power up WAIT HERE

BEGIN:
NAP 0 'REDUCE BATTERY DRAIN
ADCIN 3,BUT
IF BUT > 100 Then begin 'BUTTON not PUSHED

table:
ADCIN 3,BUT
Pause 100
ADCIN 3,BUT2
IF BUT <> BUT2 Then TABLE 'RE-READ ADC should both be same

IF BUT < 91 AND BUT > 71 Then (DO FUNCTION 1)
IF BUT < 50 AND BUT > 40 Then (DO FUNCTION 2)
IF BUT < 15 AND BUT > 8 Then (DO FUNCTION 3)
IF BUT < 8 AND BUT > 4 Then (DO FUNCTION 4)
IF BUT < 5 AND BUT > 2 Then (DO FUNCTION 5) '1K & 2.2K BUTTON PUSHED @ SAME TIME
GOTO BEGIN

[fratello]

Thank you !
As I say, with just one resistors chain , everything works PERFECT !
My troubles appears when I try to use TWO resistors chains (and TWO ADC channel).
I wrote another version :

@ __config _XT_OSC & _WDT_OFF & _PWRTE_ON & _MCLRE_ON & _BODEN_ON & _CP_ON 

DEFINE OSC  4

DEFINE ADC_BITS     10          
DEFINE ADC_CLOCK    3
DEFINE ADC_SAMPLEUS 100      



CMCON = 7
OPTION_REG.7= 1
TRISIO      = %00000110	 		
GPIO        = %00000001
ANSEL       = %00110110
ADCON0.7    = 1

adval   var word
valb    var word
vala    var word

PAUSE 200

goto mainloop

getadv:
        PAUSEuS 50                      	' Wait for A/D channel acquisition time
        ADCON0.1 = 1
        WHILE ADCON0.1 = 1 : WEND
        adval.HighByte = ADRESH
        adval.LowByte = ADRESL
Return

getadvala:
        ADCON0 = %10000101             		
        Gosub getadv
        vala=adval
Return

getadvalb:
        ADCON0 = %10001001            		
        Gosub getadv
        valb=adval
Return

mainloop:
gosub getadvala
gosub getadvalb


if vala < 950 then
	if vala < 940 AND vala > 650 THEN gosub LED1
	IF vala < 600 AND vala > 450 THEN gosub LED2      
	IF vala < 400 AND vala > 150 THEN gosub LED3     
	IF vala < 100 THEN gosub LED4                  
endif

if valb < 950 then
	if valb < 940 AND valb > 650 THEN gosub LED1
	IF valb < 600 AND valb > 450 THEN gosub LED2
	IF valb < 400 AND valb > 150 THEN gosub LED3 
	IF valb < 100 THEN gosub LED4                   
endif

goto mainloop

But still no have proper results ...

[fratello]

My schematic/code are from here : http://www.imdb.com/title/tt0052520/ !!!
I did it work ... by re-reversing all those commands :
" If VALA > 650 and VALA < 940 Then Gosub LED1"" ...
instead of :
" If VALA < 940 and VALA > 650 Then Gosub LED1"

Nothing else ! And now everything works just fine !
Thank you all for support !
Have a Nice and Happy Easter !