small tape support + turbo mode tweaks

Makefile

@@ -45,6 +45,7 @@ SRCDIR_KERNAL  = $(SRCDIR_COMMON) \
                  src/kernal/assets \
                  src/kernal/board_crt \
                  src/kernal/board_m65 \
+                 src/kernal/board_u64 \
                  src/kernal/board_x16 \
                  src/kernal/extapi_m65 \
                  src/kernal/iec \

src/aliases/,aliases_ram_lowmem.s

@@ -121,7 +121,7 @@
 !ifndef CONFIG_LEGACY_SCNKEY {
 	!addr BITTS     = $B4  ;          -- NOT IMPLEMENTED --
 }
-	!addr NXTBIT    = $B5  ;          -- NOT IMPLEMENTED -- [!] also used by tape routine, we use it only for Ultimate 64 turbo handling
+	!addr NXTBIT    = $B5  ;          -- NOT IMPLEMENTED -- [!] also used by tape routine to store CPU turbo settings
 !ifndef CONFIG_LEGACY_SCNKEY {
 	!addr RODATA    = $B6  ;          -- NOT IMPLEMENTED --
 }

src/basic/,imports.s

@@ -41,3 +41,10 @@
 ;; #ALIAS# M65_MODEGET         = KERNAL_0.M65_MODEGET
 ;; #ALIAS# M65_MODESET         = KERNAL_0.M65_MODESET
 ;; #ALIAS# M65_SETWIN_Y        = KERNAL_0.M65_SETWIN_Y
+
+;
+; Ultimate 64 specific parts
+;
+
+;; #ALIAS# U64_SLOW            = KERNAL_0.U64_SLOW
+;; #ALIAS# U64_FAST            = KERNAL_0.U64_FAST

src/basic/basic_commands_01/cmd_fast_slow.s

@@ -39,22 +39,13 @@ cmd_slow_fast_common:
 
 cmd_slow:
 
-	lda #$00                           ; for U64_TURBOCTL - badlines, 1MHz
 	sta SCPU_SPEED_NORMAL              ; any value will do
-
-	; FALLTROUGH
-
-cmd_slow_fast_common:
-
-	sta U64_TURBOCTL
-	rts
+	jmp U64_SLOW                       ; to set turbo in $D031 too
 
 cmd_fast:
 
-	lda #$0F                           ; for U64_TURBOCTL - badlines, 48MHz
 	sta SCPU_SPEED_TURBO               ; any value will do
-
-	bne cmd_slow_fast_common           ; branch always
+	jmp U64_FAST                       ; to set turbo in $D031 too
 
 } else ifdef CONFIG_PLATFORM_COMMODORE_64 {
 

src/kernal/board_m65/mega65_tape_fast_cpu.s

@@ -0,0 +1,31 @@
+;; #LAYOUT# M65 KERNAL_1 #TAKE
+;; #LAYOUT# *   *        #IGNORE
+
+;
+; Tape helper routine
+;
+; - unlocks VIC-IV
+; - switches CPU to fast processing mode and disables badlines
+; - stores previous VIC_CTRLB in NXTBIN
+;
+
+!ifdef HAS_TAPE {
+
+
+tape_fast_cpu:
+
+	jsr M65_MODEGET
+	bcc @1
+	
+	jsr viciv_unhide
+@1:
+	lda VIC_CTRLB
+	ora #%01000000
+	sta VIC_CTRLB
+	sta NXTBIT
+
+	lda #$00
+	sta MISC_EMU
+
+	rts
+}

src/kernal/board_u64/ultimate64_slow_fast.s

@@ -0,0 +1,22 @@
+;; #LAYOUT# STD *        #TAKE
+;; #LAYOUT# *   KERNAL_0 #TAKE
+;; #LAYOUT# *   *        #IGNORE
+
+
+!ifdef CONFIG_MB_U64 {
+
+U64_SLOW:
+
+	lda #$00                           ; for U64_TURBOCTL - badlines, 1MHz
+
+	+skip_2_bytes_trash_nvz
+
+	; FALLTROUGH
+
+U64_FAST:
+
+	lda #$0F                           ; for U64_TURBOCTL - badlines, 48MHz
+	sta SCPU_SPEED_TURBO               ; any value will do
+
+	rts
+}

src/kernal/init/fce2.hw_entry_reset.s

@@ -32,6 +32,12 @@ hw_entry_reset:
 	jsr m65_reset_part
 }
 
+!ifdef CONFIG_MB_U64 {
+
+	jsr U64_SLOW
+	sta SCPU_SPEED_NORMAL
+}
+
 !ifdef CONFIG_PLATFORM_COMMODORE_64 {
 
 	; The following routine is based on reading the public KERNAL jumptable routine

src/kernal/tape/tape_common_screen.s

@@ -30,8 +30,7 @@ tape_screen_on_motor_off:
 	lda #$03
 	sta MISC_EMU
 
-	lda VIC_CTRLB
-	and #%10111111
+	lda NXTBIT
 	sta VIC_CTRLB
 
 	sta VIC_KEY
@@ -70,18 +69,7 @@ tape_screen_off_motor_on:
 	; to be handled by 1 MHz CPU - so in case of compatibility mode, switch CPU to fast speed
 	; (and disable badlines, so we will not have to blank the screen)
 
-	jsr M65_MODEGET
-	bcc @2
-	
-	jsr viciv_unhide
-
-	lda VIC_CTRLB
-	ora #%01000000
-	sta VIC_CTRLB
-
-	lda #$00
-	sta MISC_EMU
-@2:
+	jsr tape_fast_cpu
 
 } else ifdef CONFIG_MB_U64 {
 
@@ -90,10 +78,8 @@ tape_screen_off_motor_on:
 	cmp #$FF
 	beq @2                             ; branch if no turbo control available
 
-	lda #$8F                           ; max speed, no badlines
-	sta U64_TURBOCTL
+	jsr U64_FAST                       ; max speed, no badlines
 	bne @3                             ; branch always
-
 @2:
 	jsr screen_off
 @3:

src/kernal/tape/tape_head_align.s

@@ -45,6 +45,17 @@ tape_head_align:
 
 	jsr nmi_lock
 
+	; Switch CPU to fast mode
+
+!ifdef CONFIG_MB_M65 {
+	jsr tape_fast_cpu
+}
+
+!ifdef CONFIG_MB_U64 {
+	jsr U64_FAST
+	sta SCPU_SPEED_TURBO
+}
+
 	; Prepare CIA timers
 
 	ldx #$02                  ; set timer A to 3 ticks