Stepper motor control board

Program 1:-
It is advisable to begin with easy program. So in this program we shall see minimal functionality. Only first two switches and first three LEDs will be used. When you press one switch the motor will start rotating in clockwise direction and stops when completes one revolution. Pressing second switch will do the same job but in anticlockwise direction. The speed will be 10 RPM fixed. Motor runs in single coil excitation mode. First LED indicates key press event. Second blinks when motor rotates clockwise and third blinks when motor rotates anticlockwise.

Org 00h
mov r0,#01h      ; initileze key count
mov p1,#0ffh      ; P1 as input port
lop:    mov a,p1
cjne a,#0ffh,jmp
ajmp lop              ; loop until any key
; is pressed
jmp:  clr p0.0               ; indicates keypress
loop:  rrc a
jnc num               ; get key no.
inc r0
sjmp loop
num: acall dely          ; key debounce delay
setb p0.0

cjne r0,#01h,nxt      ; for 1st key
acall clkwise             ; rotate motor
sjmp over                 ; clock wise
nxt:    cjne r0,#02h,over ; for 2nd key
acall aclkwise          ; rotate anticlock

over:  mov p2,#00h        ; restore initial
mov p1,#0ffh           ; data and
mov r0,#01h
sjmp lop                   ; jump to loop again

clkwise:
mov r1,#32h           ; load count 50d
go: clr  p0.1
mov p2,#01h          ;give 4 pulses in loop
acall delay              ; total 200 pulses
mov p2,#02h          ; each coil energized
acall delay              ; one by on in single
setb p0.1
mov p2,#04h          ; coil excitation
acall delay              ; 30 ms delay in betwn
mov p2,#08h          ; means speed is
acall delay              ; 10 RPM
djnz r1,go
ret
aclkwise:
mov r1,#32h
go1:clr p0.2
mov p2,#01h
acall delay
mov p2,#08h       ; revert the pulse
acall delay           ; sequence for
setb p0.2
mov p2,#04h       ; anticlockwise
acall delay
mov p2,#02h
acall delay
djnz r1,go1
ret

delay:
mov r5,#1Eh        ; load count 30
lop2: mov r6,#FAh     ; give 1 ms delay
lop1:nop                    ; so it gives full
nop                       ; 30 ms delay
djnz r6,lop1
djnz r5,lop2
ret

dely:
mov r5,#0C8h      ; load count 200
lop2: mov r6,#0FAh   ; for 200ms delay
lop1: nop
nop
djnz r6,lop1
djnz r5,lop2
ret
end
Program 2:-
Here in this program we shall limit the motor to rotate only 7.2o in either direction when the key is pressed. When first key is pressed motor rotates in clockwise direction and when second is pressed anticlockwise direction. LED1 and LED2 indicate the clockwise and anticlockwise rotation.
Note: – In industries this is also known as “jogging” (jog control). This is done to check in which direction motor will start running.

Org 00h
mov r0,#01h                     ; initileze key count
mov p1,#0ffh                    ; P1 as input port
lop:   mov a,p1
cjne a,#0ffh,jmp
ajmp lop                             ; loop until any key is pressed
jmp:     clr p0.0                   ; indicates keypress
loop:    rrc a
jnc num                              ; get key no.
inc r0
sjmp loop
num: acall dely                  ; key debounce delay
setb p0.0

cjne r0,#01h,nxt               ; for 1st key
acall clkwise                      ; rotate motor
sjmp over                          ; clock wise
nxt: cjne r0,#02h,over      ; for 2nd key
acall aclkwise                    ; rotate anticlock

over:   mov p2,#00h         ; restore initial
mov p1,#0ffh                     ; data and
mov r0,#01h
sjmp lop                             ; jump to loop again

clkwise:
clr p0.1
mov p2,#01h                     ;give 4 pulses in loop
acall delay                         ; as 1.8o step resolution
mov p2,#02h                     ; total 7.2o rotation
acall delay                         ; in single coil
setb p0.1
mov p2,#04h                     ; excitation
acall delay                         ; 30 ms delay in betwn
mov p2,#08h                     ; means speed is
acall delay                         ; 10 RPM
ret
aclkwise:
clr p0.1
mov p2,#01h
acall delay
mov p2,#08h                     ; revert the pulse
acall delay                          ; sequence for
setb p0.1
mov p2,#04h                     ; anticlockwise
acall delay
mov p2,#02h
acall delay
ret

delay:
mov r5,#1Eh                      ; load count 30
lop2: mov r6,#FAh             ; give 1 ms delay
lop1:nop                            ; so it gives full
nop                                    ; 30 ms delay
djnz r6,lop1
djnz r5,lop2
ret

dely:
mov r5,#0C8h                    ; load count 200
lop2: mov r6,#0FAh           ; for 200ms delay
lop1:nop
nop
djnz r6,lop1
djnz r5,lop2
ret
end