In SX Microcontrollers, SX/B Compiler and SX-Key Tool, roondog wrote:

I do not need to debounce the pushbutton. I found a sample program in the [u]Exploring the SX[/u] pdf that uses a pushbutton with a piezoelectric speaker instead of an LED. The document says that the button is wired to read a 0 when the button is pressed but I would like it to read a 1 when pressed. The segment of code that controls this is: [b]jb rb.0, bwait, [/b]so jump to the "bwait" subroutine if register b is set. I changed the jb command to [b]jnb[/b] but the button still reads 0 when pressed. Is there an easy way to fix this? The program is as follows:

[1]device sx28l,oschs3[/1]

[1]device turbo,stackx,optionx

IRC_CAL IRC_SLOW

reset start_point

freq 50000000 ; 50 MHz

org 8
[/1][1]
second ds 2 ; counter for 1 second tone

delay ds 1

delay1 ds 1

              org 0

start_point   mov !rb,#$7F ; make speaker output

              call beep

; wait for input button

bwait         jb rb.0,bwait

              call beep

              jmp bwait

; subroutine

beep          mov second,#$d0 ; 2000 is $7D0

              mov second+1,#$07

loop          not rb ; toggle bits

              mov delay1,#24

oloop         clr delay

wloop         djnz delay,wloop

              djnz delay1,oloop

; repeat 2000 times

              djnz second,loop

              djnz second+1,loop

              ret ; go back to wherever

[/1]

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