I have done software debounce logic with 2/3 voter logic and kindly verify the coding i don't no whether it is correct or not. Please help me
Coding:
void inputRoutine() { uint16_t temp; InputP1_Temp=P1&0x00; for(Index1=0;Index1<MAXINPUTS;Index1++) { temp=debounce(Index1); if(temp==1) { Input_TableP1[Index1]=1; } else if(temp==0) { Input_TableP1[Index1]=0; } } } /***************** -- Debounce Port P1 -- *****************/ bit debounce(uint16_t IN_INDEX) { uint16_t INDEX2,ONE=0,ZERO=0; char TEMP,SHIFT_RESULT[3]=0x00; for(INDEX2=0;INDEX2<3;INDEX2++) { TEMP= P1; SHIFT_RESULT[INDEX2]=(TEMP>>IN_INDEX)& 0x01; delay_10micro_sec(); } /* Comparision of 3 values retreived from same pin*/ for(INDEX2=0;INDEX2<3;INDEX2++) { if(SHIFT_RESULT[INDEX2]==1) ONE++; else if(SHIFT_RESULT[INDEX2]==0) ZERO++; } return (ONE>ZERO); }
With Thanks, G.Karthik Ragunath
As a matter of fact - all uses of external RC filters should be avoided unless the input has hysterese. one more reason to avoid RC filters is that it slows down the input. Many moons ago (before the micro, with a mini) I did some investigation on RC filtering and found that (for this particular app, how general I do not know) sufficient RC filtering made the thingy fail to respnd to the "fastest fingers"
And since the debounce is so easy to do in software, there is no real need to figure out ways to let the hardware help. I second that opinion
Erik