.data
********************************************************************
** Decomposition matrices indexed by the sector, s, Uout is in **
********************************************************************
decomp_ .WORD 20066 ; D1–scaled by 2 to the 14th power
.WORD -11585
.WORD 0
.WORD 23170
.WORD -20066
.WORD 11585
.WORD 20066
.WORD 11585
.WORD 0
.WORD 23170
.WORD -20066
.WORD -11585
.WORD 0
.WORD -23170
.WORD -20066
.WORD 11585
.WORD -20066
.WORD -11585
.WORD 20066
.WORD -11585
.WORD 20066
.WORD 11585
.WORD 0
.WORD -23170
; .
; .
.bss decomp,24 ; decomposition matrices
.bss temp,1 ; temporary storage
.txt
********************************************************************
** Initialize the decomposition matrices **
********************************************************************
LAR AR0,#decomp ; Point to 1st destination
LAR AR1,#(24-1) ; 24 entries
LACC #decomp_ ; Point to 1st data item
MAR *,AR0 ; Point to AR0
init_table
TBLR *+,1 ; Move data&pnt to nextdesti.
ADD #1 ; Point to next data item
   BANZ init_table,0        ; Continue if there is more
; .
; .
;-------------------------------------------------------------------
; Calculate T1&T2 as compare values based on: Tpwn Uout=V1*T1+V2*T2
;
; i.e. [T1 T2]=Tpwn*inverse[V1 V2]*Uout
; i.e. [0.5*T1 0.5*T2]=Tp*inverse[V1 V2]*Uout
; i.e. [0.5*C1 0.5*C2]=inverse[V1 V2]*Uout=M(sector)*Uout
; where C1=T1/Tp, C2=T2/Tp, are normalized T1&T2 wrt Tp
; M(sector)=inverse of [V1 V2] = decomposition matrix
; obtained through table lookup
; Uout=Transpose of [Ud Uq]
; Tp=Timer 1 period = 0.5*Tpwm
; Tpwm=PWM period Tpwm
; Input S: sector of Uout (0-5)
; Ud: d compo. of Uout(0-1/sqrt(2)), D2(Scaled by 2**13)
; Uq: q compo. of Uout(0-1/sqrt(2)), D2(Scaled by 2**13)
; t1_period_: Timer period (for PWM freq)
; t1_periods: Timer period in D10 (Scaled by 2**5)
; Output cmp_0: 0.5(1-0.5C1-0.5C2)Tp cmp value for 1st-to-tog ch
; cmp_1: cmp_0+0.5C1Tp cmp value for 2nd-to-tog ch
; cmp_2: cmp_1+0.5C2Tp cmp value for 3rd-to-tog ch
;--------------------------------------------------------------------
   LACC #decomp            ;
   ADD S,2                 ;
   SACL temp               ; get the pointer
   LAR AR0,temp            ; point to parameter table
; Calculate 0.5C1 based on 0.5C1=Ud*M(1,1)+Uq*M(1,2)
   LT Ud                   ; D2
   MPY *+                  ; M(1,1) Ud: D2*D1=D(3+1)
   PAC                     ; D4
   LT Uq                   ; D4
   MPY *+                  ; M(1,2) Uq: D2*D1=D(3+1)
   APAC                    ; 0.5*C1: D4+D4=D4
   BGEZ cmp1_big0          ; continue if bigger than zero
   ZAC                     ; set to 0 if less than zero
   cmp1_big0 SACH temp     ; D4
   LT temp                 ; D4
   MPY t1_periods          ; *Tp: D4*D10 = D(14+1)
   PAC                     ;
   Sach cmp_1              ; 0.5C1Tp: D15 (integer)
; Calculate 0.5C2 based on 0.5C2=Ud*M(2,1)+Uq*M(2,2)
LT Ud ; D2
MPY *+ ; M(2,1) Ud: D2*D1=D(3+1)
PAC ; D4
LT Uq ; D4
MPY *+ ; M(2,2) Uq: D2*D1=D(3+1)
APAC ; 0.5*C2: D4+D4=D4
BGEZ cmp2_big0 ; continue if bigger than zero
ZAC ; zero it if less than zero
cmp2_big0 SACH temp ; D4
LT temp ; D4
MPY t1_periods ; *Tp: D4*D10 = D(14+1)
PAC ;
Sach cmp_2 ; 0.5C2Tp: D15 (integer)
; Calculate compare value 3 based on 0.5C0Tp=(1-0.5C1-0.5C2)Tp
LACC #t1_period_ ; Calculate 0.5*C0
SUB cmp_1 ;
SUB cmp_2 ; 0.5*C0Tp = (1-0.5*C1 -0.5*C2)Tp: D15
BGEZ cmp0_big0 ; continue if bigger than zero
ZAC ; zero it if less than zero
cmp0_big0 sfr ; divide by 2
SACH cmp_0 ; 0.25*C0Tp: D15 (integer)