SET      0.050 1 0

                VAR    V1,minPrd=s(0.5)
                VAR    V2,maxPrd=s(2.0)
                VAR    V3,prdSteps=4

                VAR    V4,minDC=20     ;percent
                VAR    V5,maxDC=80
                VAR    V6,DCSteps=4

                VAR    V7,numPulse=10
                VAR    V8,hold=S(2)

				;end of user vars

                VAR    V9,period
                VAR    V10,DC
                VAR    V11,upTime
                VAR    V12,downTime

                VAR    V13,prdInc
                VAR    V14,DCInc

                VAR    V15,stepI
                VAR    V16,stepJ
                VAR    V17,stepK


                VAR    V18,numer       ;must be set before call
                VAR    V19,denom       ;must be set before call
                VAR    V20,result      ;must be 0 before call

0000         'q DIGOUT [00001000]
0001            HALT   

				;setup period
0002         's MOV    period,minPrd
0003            MOV    stepI,prdSteps
0004            MOV    prdInc,maxPrd
0005            SUB    prdInc,minPrd
0006            MOV    numer,prdInc
0007            MOV    denom,prdSteps
0008            ADDI   denom,-1
0009            MOVI   result,0
0010            CALL   DIVIDE
0011            MOV    prdInc,result

				;setup duty cycle
0012            MOV    DCInc,maxDC
0013            SUB    DCInc,minDC
0014            MOV    numer,DCInc
0015            MOV    denom,DCSteps
0016            ADDI   denom,-1
0017            MOVI   result,0
0018            CALL   DIVIDE
0019            MOV    DCInc,result

0020 PRDLOOP:   MOV    DC,minDC
0021            MOV    stepJ,DCSteps

0022 DCLOOP:    MOV    numer,period
0023            MOVI   denom,100       ;percent
0024            MOVI   result,0
0025            CALL   DIVIDE
0026            MOV    downTime,result
0027            MUL    downTime,DC
0028            MOV    upTime,period
0029            SUB    upTime,downTime
0030            MOV    stepK,numPulse

0031 PLSLOOP:   DIGOUT [00100000]
0032            DELAY  upTime
0033            DIGOUT [00001000]
0034            DELAY  downTime
0035            DBNZ   stepK,PLSLOOP
	;PLSLOOP DONE

0036            DELAY  hold
0037            ADD    DC,DCInc
0038            DBNZ   stepJ,DCLOOP
	;DCLOOP DONE

0039            ADD    period,prdInc
0040            DBNZ   stepI,PRDLOOP
	;PRDLOOP DONE

0041            DIGOUT [00001000]
0042            HALT   


0043 DIVIDE:    BGT    denom,numer,DONE
0044            SUB    numer,denom
0045            ADDI   result,1
0046            JUMP   DIVIDE
0047 DONE:      RETURN