![]() |
Routines |
HL | Base address of tune data table |
32279 | DI | Disable interrupts |
32280 | LD A,(HL) | Pick up a tune datum in A |
32281 | INC HL | Point HL at the next tune datum |
32282 | AND A | Is the tune finished? |
32283 | JR NZ,32290 | Jump if not |
32285 | INC A | Make the border blue |
32286 | OUT (254),A | |
32288 | EI | Re-enable interrupts |
32289 | RET |
32290 | PUSH HL | |
32291 | LD B,A | Copy the tune datum to B |
32292 | RRCA | Should we pause briefly (bit 0 set) here? |
32293 | JR NC,32304 | Jump if not |
32295 | LD DE,3840 | Pause briefly (this happens for all but one note in the theme tune, and for all notes in the 'all shields/safe' tune) |
32298 | DEC E | |
32299 | JR NZ,32298 | |
32301 | DEC D | |
32302 | JR NZ,32298 | |
32304 | AND 7 | 0<=A<=7 |
32306 | LD C,A | C=border colour for this note |
32307 | ADD A,A | 0<=A<=14 (even) |
32308 | ADD A,7 | 7<=A<=21 (odd) |
32310 | LD L,A | Point HL at the appropriate entry in the note pitch/duration data table at 32263-32278 |
32311 | LD H,126 | |
32313 | LD A,B | A=original tune datum |
32314 | RLCA | Obtain the note frequency parameter in E and the note duration parameter in HL |
32315 | RLCA | |
32316 | RLCA | |
32317 | RLCA | |
32318 | AND 15 | |
32320 | LD B,A | |
32321 | LD E,(HL) | |
32322 | INC L | |
32323 | LD A,(HL) | |
32324 | LD HL,0 | |
32327 | ADD HL,DE | |
32328 | DJNZ 32327 | |
32330 | RR H | |
32332 | RR L | |
32334 | LD E,A | |
32335 | LD A,C | Produce a note |
32336 | OUT (254),A | |
32338 | XOR 16 | |
32340 | LD C,A | |
32341 | LD B,E | |
32342 | DJNZ 32342 | |
32344 | DEC HL | |
32345 | LD A,H | |
32346 | OR L | |
32347 | JR NZ,32335 | |
32349 | POP HL | Restore the pointer to the tune data table |
32350 | JP 32280 | Pick up the next tune datum |