diff options
Diffstat (limited to 'src-z80/core/main.z80')
| -rw-r--r-- | src-z80/core/main.z80 | 113 |
1 files changed, 48 insertions, 65 deletions
diff --git a/src-z80/core/main.z80 b/src-z80/core/main.z80 index 4eb6e5a..387b879 100644 --- a/src-z80/core/main.z80 +++ b/src-z80/core/main.z80 @@ -4,10 +4,11 @@ ;**************************************************************************** EntryPoint: - ld sp, RAM_Stack ; Init stack + xor a ; Reset Echo status (we don't clear + ld (RAM_Status), a ; RAM_Command since Echo_Init fills in values + ld (RAM_Command2), a ; before Echo gets to run!) - xor a ; Reset Echo status - ld (RAM_Status), a + ld sp, RAM_Stack ; Init stack ld hl, $7F11 ; Mute PSG ld (hl), $9F @@ -88,22 +89,11 @@ EntryPoint: jp IdleLoop ; Go into idle loop ;**************************************************************************** -; PollPCM -; Used to update PCM while not idle -;---------------------------------------------------------------------------- -; breaks: af -;**************************************************************************** - -PollPCM: macro - ld a, ($4000) - rrca - call c, UpdatePCM - endm - -;**************************************************************************** ; RunCommand ; Checks which command to run ;---------------------------------------------------------------------------- +; notes: doesn't return +;---------------------------------------------------------------------------- ; To-do: replace with pointer list? ;**************************************************************************** @@ -122,17 +112,36 @@ RunCommand: jp z, ResumeBGM dec a ; Command $07: set PCM rate jp z, SetPCMRate + dec a ; Command $08: pause BGM + jp z, PauseBGM PollPCM - xor a ; Bad command, ignore >:( - ld (RAM_Command), a + ; Bad command, ignore >:( + +;**************************************************************************** +; EndOfCommand +; Cleans up when a command finishes +;---------------------------------------------------------------------------- +; notes: doesn't return +;**************************************************************************** +EndOfCommand: + ld hl, ($1FF8) ; Copy second slot into first + ld ($1FFC), hl + ld hl, ($1FFA) + ld ($1FFE), hl + + xor a ; Free up second slot + ld (RAM_Command2), a + PollPCM ;**************************************************************************** ; IdleLoop ; Loop that runs when not processing SFX or BGM +;---------------------------------------------------------------------------- +; notes: doesn't return (d'oh) ;**************************************************************************** IdleLoop: @@ -153,13 +162,11 @@ IdleLoop: ;**************************************************************************** ; DoTick ; Called whenever a new tick triggers +;---------------------------------------------------------------------------- +; notes: doesn't return ;**************************************************************************** DoTick: -; ld a, (ix+0) -; bit 0, a -; call nz, UpdatePCM - PollPCM ld (ix+0), $27 ; Retrigger the timer @@ -181,6 +188,9 @@ DoTick_SFXSkip: PollPCM + ld a, (RAM_Paused) ; BGMs are paused? + or a + jr nz, DoTick_BGMSkip DoTick_BGM: ; Process BGMs jp DoTick_BGMSkip DoTick_BGMSkip: @@ -195,57 +205,30 @@ DoTick_PSGSkip: jp IdleLoop ; End of subroutine ;**************************************************************************** -; BankSwitch -; Switches into a new bank (won't update player status!) -; -; input A .... New bank to switch into -; input HL ... Must be $6000 -; breaks ..... AF -;**************************************************************************** - -BankSwitch: macro - ld (hl), a - rrca - ld (hl), a - rrca - ld (hl), a - rrca - ld (hl), a - rrca - ld (hl), a - rrca - ld (hl), a - rrca - ld (hl), a - ld (hl), h - rrca - ld (hl), a - endm - -;**************************************************************************** ; LoadList [command $01] ; Loads the pointer list ;**************************************************************************** LoadList: - ld hl, RAM_ComBank ; Get command parameters - ld c, (hl) - inc l - ld e, (hl) - inc l - ld d, (hl) - ex de, hl - - xor a ; Command parsed - ld (RAM_Command), a +; ld hl, RAM_ComBank ; Get command parameters +; ld c, (hl) +; inc l +; ld e, (hl) +; inc l +; ld d, (hl) +; ex de, hl + + ld hl, (RAM_ComAddr) ; Get command parameters + ld a, (RAM_ComBank) + ld c, a ld de, RAM_PointerList ; Where the pointer list starts -.loop: +.loadloop: call GetParam ; Get high byte address ld a, b ; Is it the end of the list? or a - jp z, .end + jp z, .loadend ld (de), a ; Store high byte address inc d @@ -261,10 +244,10 @@ LoadList: dec d ; Go for next byte dec d inc e - jp .loop + jp .loadloop -.end: - jp IdleLoop ; End of subroutine +.loadend: + jp EndOfCommand ; End of subroutine ;**************************************************************************** ; GetParam |