Routines
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47440: Initialise Explosion
Copy an 8-byte explosion template into Explosion_Slot, which starts a sound. The entry point at InitialiseExplosion_Copy takes the template address in HL.
There are five templates. The first is read by TickWaveDuration (type 165) and the other four by TickWaveTable (type 161).
InitialiseExplosion 47440 LD HL,47452 HL=Explosion_Template_1.
InitialiseExplosion_Copy 47443 LD DE,24672 DE=Explosion_Slot.
47446 LD BC,8 Copy 8 bytes from HL to DE.
47449 LDIR
47451 RET Return.
Template for TickWaveDuration. It plays one note on each pass, starting from the pitch below and counting down to 1 so the sound rises over 39 notes. Nothing calls InitialiseExplosion, so this one is never used. The copy at InitialiseExplosion_Copy takes four more bytes than this, which are the first instructions at Copy_Explosion_Template, but TickWaveDuration never reads them.
Explosion_Template_1 47452 DEFB 165 Actor type, handled by TickWaveDuration.
47453 DEFB 32 Not read by TickWaveDuration.
47454 DEFB 8 Repeat count: each note is played 8 times.
47455 DEFB 40 Starting pitch.
This entry point is used by the routines at Handler_PlayerShot and Handler_Missile_ConvertExploding.
Copy_Explosion_Template 47456 LD HL,47461 HL=Explosion_Template_2.
47459 JR InitialiseExplosion_Copy Jump to InitialiseExplosion_Copy.
Template for TickWaveTable: seven notes of falling pitch, each played 8 times.
Explosion_Template_2 47461 DEFB 161 Actor type, handled by TickWaveTable.
47462 DEFB 8 Counter: a value of 8 gives seven notes.
47463 DEFW 47466 Address of the pitch table minus one.
47465 DEFB 8 Repeat count: each note is played 8 times.
47466 DEFB 0 Index 0 of the pitch table, which is never read.
47467 DEFB 120,112,104,96,88,80,72 Pitch table, played from the last byte back to the first.
47474 DEFB 64 Never played, as the counter reaches zero first.
InitialiseExplosion_2 47475 LD HL,47480 HL=Explosion_Template_Burst.
47478 JR InitialiseExplosion_Copy Jump to InitialiseExplosion_Copy.
Template for TickWaveTable: seven notes of rising pitch, each played 16 times.
Explosion_Template_Burst 47480 DEFB 161 Actor type, handled by TickWaveTable.
47481 DEFB 8 Counter: a value of 8 gives seven notes.
47482 DEFW 47485 Address of the pitch table minus one.
47484 DEFB 16 Repeat count: each note is played 16 times.
47485 DEFB 0 Index 0 of the pitch table, which is never read.
47486 DEFB 64,72,80,88,96,96,104 Pitch table, played from the last byte back to the first.
47493 DEFB 112 Never played, as the counter reaches zero first.
InitialiseExplosion_3 47494 LD HL,47499 HL=Explosion_Template_3.
47497 JR InitialiseExplosion_Copy Jump to InitialiseExplosion_Copy.
Template for TickWaveTable: fifteen notes that swap between two pitches in runs of up to four, each note played 6 times.
Explosion_Template_3 47499 DEFB 161 Actor type, handled by TickWaveTable.
47500 DEFB 16 Counter: a value of 16 gives fifteen notes.
47501 DEFW 47504 Address of the pitch table minus one.
47503 DEFB 6 Repeat count: each note is played 6 times.
47504 DEFB 0 Index 0 of the pitch table, which is never read.
47505 DEFB 64,64,64,64,80,80,80,80 Pitch table, played from the last byte back to the first.
47513 DEFB 64,64,64,64,80,80,80
47520 DEFB 80 Never played, as the counter reaches zero first.
InitialiseExplosion_4 47521 LD HL,47526 HL=Explosion_Template_4.
47524 JR InitialiseExplosion_Copy Jump to InitialiseExplosion_Copy.
Template for TickWaveTable: fifteen notes of falling pitch, each played 6 times.
Explosion_Template_4 47526 DEFB 161 Actor type, handled by TickWaveTable.
47527 DEFB 16 Counter: a value of 16 gives fifteen notes.
47528 DEFW 47531 Address of the pitch table minus one.
47530 DEFB 6 Repeat count: each note is played 6 times.
47531 DEFB 0 Index 0 of the pitch table, which is never read.
47532 DEFB 80,78,76,74,72,70,68,66 Pitch table, played from the last byte back to the first.
47540 DEFB 64,62,60,58,56,54,52
47547 DEFB 50 Never played, as the counter reaches zero first.
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