2.3 Relaxatie-oscillator

ajmp sendmd2
ajmp waittx
ajmp caseovr
;*****************************************************************************
;* cptfull -> np_flag, OP_0..3, R2, R3 *
;* from interrupt proces there might be enough captured date, to proces *
;* further here: calculate average. When finished next task *
;* OP_0..3 *
;* The summing must be converted to a proper midi value (0..127) *
;* midival is only stored if it is different from calculated value in acc. *
;* If they’re equal, the dispatcher starts from beginning, so byte will not *
;* be transmitted. *
;* (OP_2..3) *
;* 256 multiply: (OP_2..3) -> (OP_1..2) *
;* division: (OP_0..3)/(wndwTH/L0) (creates value 0..255) *
;* linearisation: array[0..255] -> 0..127 *
;*****************************************************************************
convert: clr C ;substr. ffffh -
mov A,#0ffh
subb A,OP_3 ;LSB
mov OP_3,A
mov A,#0ffh ;MSB
subb A,OP_2
mov OP_1,A ;store result in OP_1..2
mov OP_2,OP_3 ;perform 256*multiply
mov OP_3,#0
mov R2,wndwTH0
mov R3,wndwTL0
acall Div_16 ;result in OP_0..3 (0..255)
mov DPTR,#lintbl ;in lintbl is a table to linearizate output
mov A,OP_3 ;index to accumulator
movc A,@A+DPTR ;move array value to accumulator
cjne A,midival,newmdi ;continue only if value is different
ajmp caseovr ;in the beginning there was...
newmdi: mov midival,A ;new value, so save value in midival
ajmp inccase
;*****************************************************************************
;* sendmd1 -> *
;* transmits first control byte midictrl *
;* *
;* transmits second midi value byte *
;* *
;* waits till byte is transmitted *
;* *
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