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base:ntsc_frequency_table

NTSC A440 frequency table

Note: Strictly speaking, this table corresponds to A440 tuning on C64s with the 6567R8 VIC, used in most NTSC machines. It is slightly incorrect on C64s with the 6567R56A VIC (which has 262 lines with 64 cycles per line instead of 263 lines with 65 cycles per line), but for most purposes it is still a relatively good approximation of A440 tuning.

FreqTableNtscLo:
	        ;      C   C#  D   D#  E   F   F#  G   G#  A   A#  B
	        .byte $0c,$1c,$2d,$3f,$52,$66,$7b,$92,$aa,$C3,$de,$fa  ; 0
	        .byte $18,$38,$5a,$7e,$a4,$cc,$f7,$24,$54,$86,$bc,$f5  ; 1
	        .byte $31,$71,$b4,$fc,$48,$98,$ed,$48,$a7,$0c,$78,$e9  ; 2
	        .byte $62,$e2,$69,$f8,$90,$30,$db,$8f,$4e,$19,$f0,$d3  ; 3 
	        .byte $c4,$c3,$d1,$f0,$1f,$61,$b6,$1e,$9d,$32,$df,$a6  ; 4
	        .byte $88,$86,$a3,$e0,$3f,$c2,$6b,$3d,$3a,$64,$be,$4c  ; 5
	        .byte $0f,$0c,$46,$bf,$7d,$84,$d6,$7a,$73,$c8,$7d,$97  ; 6
	        .byte $1e,$18,$8b,$7f,$fb,$07,$ac,$f4,$e7,$8f,$f9,$2f  ; 7

FreqTableNtscHi:
	        ;      C   C#  D   D#  E   F   F#  G   G#  A   A#  B
	        .byte $01,$01,$01,$01,$01,$01,$01,$01,$01,$01,$01,$01  ; 0
	        .byte $02,$02,$02,$02,$02,$02,$02,$03,$03,$03,$03,$03  ; 1
	        .byte $04,$04,$04,$04,$05,$05,$05,$06,$06,$07,$07,$07  ; 2
	        .byte $08,$08,$09,$09,$0a,$0b,$0b,$0c,$0d,$0e,$0e,$0f  ; 3 
	        .byte $10,$11,$12,$13,$15,$16,$17,$19,$1a,$1c,$1d,$1f  ; 4
	        .byte $21,$23,$25,$27,$2a,$2c,$2f,$32,$35,$38,$3b,$3f  ; 5
	        .byte $43,$47,$4b,$4f,$54,$59,$5e,$64,$6a,$70,$77,$7e  ; 6
	        .byte $86,$8e,$96,$9f,$a8,$b3,$bd,$c8,$d4,$e1,$ee,$fd  ; 7
base/ntsc_frequency_table.txt · Last modified: 2023-07-08 05:21 by acrouzet