;************************************** ; DIPOLE (2 VOICE) IRQ PLAYER FOR COCO ; (C) SIMON JONASSEN 2017 ;************************************** opt 6809 opt cd ORG $0E00 align $100 * Make sure the code starts at a 256 byte block since we use the Direct Page DirectPage: ;************************************** ;equal tempered 12 note per ;octave frequency table (7.875 Khz) ; ;NOTES ARE AS FOLLOWS ;THE LOWEST C HERE IS NOT PLAYED ;IT'S USED FOR SILENCE ; ;notes C,C#,D,Eb,E,F,F#,G,G#,A,Bb,B ;************************************** freqtab ;c1 fdb 0,141,149,158,167,177,188,199,211,223,237,251 c2 fdb 0,282,298,316,335,355,376,398,422,447,474,502 c3 fdb 532,563,597,632,670,710,752,796,844,894,947,1003 c4 fdb 1063,1126,1193,1264,1339,1419,1503,1593,1688,1788,1894,2007 c5 fdb 2126,2253,2387,2529,2679,2838,3007,3186,3375,3576,3789,4014 c6 fdb 4252,4505,4773,5057,5358,5676,6014,6371,6750,7152,7577,8028 c7 fdb 8505,9011,9546,10114,10716,11353,12028,12743,13501,14303,15154,16055 c8 fdb 17010,18021,19093,20228,21431,22705,24056,25486,27001,28607,30308,32110 ;************************************** ; 2 VOICE NOTE ROUTINE ;************************************** opt cc opt ct note sum ldd #$0000 ;CH1 OSCILLATOR freq addd #$0000 std