Fixed FM volume restoring bug (I hope?)

6 files changed, 23 insertions, 26 deletions

diff --git a/built/prog-z80.bin b/built/prog-z80.bin
index c9ee810..55ce59d 100644
--- a/built/prog-z80.bin
+++ b/built/prog-z80.bin
diff --git a/src-z80/core/bgm.z80 b/src-z80/core/bgm.z80
index ebda240..27cb89c 100644
--- a/src-z80/core/bgm.z80
+++ b/src-z80/core/bgm.z80
@@ -42,15 +42,15 @@ PlayBGM:
     ld hl, ProcessBGM           ; Tell Echo to process BGM
     ld (DoTick_BGM+1), hl
     
-    ld b, 8                     ; Kill all FM channels explicitly
-.resetallfm:
-    ld a, b
-    and $04
-    rrca
-    ld iyl, a
-    ld a, b
-    call KillFM
-    djnz .resetallfm
+;    ld b, 8                     ; Kill all FM channels explicitly
+;.resetallfm:
+;    ld a, b
+;    and $04
+;    rrca
+;    ld iyl, a
+;    ld a, b
+;    call KillFM
+;    djnz .resetallfm
 
     jp IdleLoop                 ; End of subroutine
 
@@ -83,6 +83,7 @@ ProcessBGM:
     ex de, hl
 
 ProcessBGMRun:
+ProcessBGMSkip:
     PollPCM                     ; Fetch next event
     call GetParam
     PollPCM
@@ -172,9 +173,6 @@ ProcessBGMSkip1:                ; This is where we land after a locked event
     inc c
 .nobankskip1:
 
-ProcessBGMSkip:                 ; This is where we land after a locked event
-    PollPCM                       ; without parameters
-
     jp ProcessBGMRun            ; Keep processing
 
 ;****************************************************************************
diff --git a/src-z80/core/main.z80 b/src-z80/core/main.z80
index bc63da9..5d9b7f6 100644
--- a/src-z80/core/main.z80
+++ b/src-z80/core/main.z80
@@ -309,7 +309,7 @@ GetParam:
 .noswitchp:
     ld b, (hl)                  ; Get volume
 
-    PollPCM
+    ;PollPCM
 
     inc l                       ; Get next address
     jp nz, .nonewbankp
diff --git a/src-z80/core/sfx.z80 b/src-z80/core/sfx.z80
index 6a553bb..d008f0b 100644
--- a/src-z80/core/sfx.z80
+++ b/src-z80/core/sfx.z80
@@ -291,12 +291,14 @@ ClearSFX:
     
     PollPCM
     
+    push bc
     ld a, b                       ; Restore BGM FM volume
     add RAM_BGMFMVol&$FF
     ld l, a
     ld a, b
     ld b, (hl)
     call SetFMVolLoad
+    pop bc
 
     PollPCM
     inc b
diff --git a/src-z80/core/vars.z80 b/src-z80/core/vars.z80
index ef9a676..8b6593a 100644
--- a/src-z80/core/vars.z80
+++ b/src-z80/core/vars.z80
@@ -15,7 +15,7 @@ RAM_PSGData:        ds 4*16         ; PSG envelope data
 
 RAM_BGMFMInstr:     ds 8            ; FM instruments used by BGM
 RAM_BGMFMVol:       ds 8            ; FM volumes used by BGM
-RAM_FMVolume:       ds 8            ; Volume of each FM channel
+;RAM_FMVolume:       ds 8            ; Volume of each FM channel
 RAM_FMData:         ds 8*5          ; FM info (for volume handling)
                                       ; ds 8*1 ... Register $B0
                                       ; ds 8*1 ... Register $40
diff --git a/src-z80/player/fm.z80 b/src-z80/player/fm.z80
index 96c9f4c..b48e79b 100644
--- a/src-z80/player/fm.z80
+++ b/src-z80/player/fm.z80
@@ -222,9 +222,8 @@ LoadFMBGM:
     PollPCM
     call GetParam
     PollPCM
-    ex de, hl
-    ld (hl), b
-    ex de, hl
+    ld a, b
+    ld (de), a
     
     ld a, e                     ; Reset volume
     add 8
@@ -240,9 +239,9 @@ LoadFMBGM:
     PollPCM
 
     push hl                     ; Check if channel is free
-    ld hl, RAM_Locked
     ld a, b
-    add l
+    ld h, RAM_Locked>>8
+    add RAM_Locked&$FF
     ld l, a
     ld a, (hl)
     pop hl
@@ -251,8 +250,7 @@ LoadFMBGM:
 
     PollPCM
 
-    ld a, b
-    and $07
+    ld a, b                     ; Get back instrument ID
     push hl
     ld hl, RAM_BGMFMInstr
     add l
@@ -260,9 +258,9 @@ LoadFMBGM:
     ld b, (hl)
     pop hl
 
-    push af
+    ex af, af'
     PollPCM
-    pop af
+    ex af, af'
 
     call LoadFMDirect           ; We're just a wrapper
     jp ProcessBGMRun            ; End of subroutine
@@ -350,8 +348,7 @@ LoadFMDirect:
     add $B0
     
     ld hl, RAM_Scratch          ; Get address of buffer with the instrument
-                                ; data
-
+                                  ; data
     ex af, af'
     PollPCM                     ; Write operator
     ex af, af'
@@ -741,7 +738,7 @@ LockChannelFM:
     rrca
     ld iyl, a
     
-    ld a, b                     ; Reset stereo
+    ld a, b                     ; Reset FM parameters
     and $03
     add a
     add a