more work on extended command set

c64/basic/basic_commands_CD/cmd_fast.s

@@ -5,4 +5,36 @@
 
 cmd_fast:
 
-	jmp do_NOT_IMPLEMENTED_error // XXX implement the command
+#if CONFIG_MB_MEGA_65
+
+	// Command implementation for Mega65
+
+	// XXX provide better implementation
+
+	jmp execute_statements
+
+#elif CONFIG_MB_ULTIMATE_64
+
+	// Try to enable turbo in SuperCPU compatible way
+	sta SCPU_SPEED_TURBO
+
+	jmp execute_statements
+
+#elif CONFIG_PLATFORM_COMMODORE_64
+
+	// Command implementation for generic C64 platform
+
+	// Try to enable turbo mode in C128 compatible way
+	lda #$01
+	sta VIC_CLKRATE
+
+	// Try to enable turbo in SuperCPU compatible way
+	sta SCPU_SPEED_TURBO
+
+	jmp execute_statements
+
+#else
+
+	jmp do_NOT_IMPLEMENTED_error
+
+#endif

c64/basic/basic_commands_CD/cmd_slow.s

@@ -5,4 +5,41 @@
 
 cmd_slow:
 
-	jmp do_NOT_IMPLEMENTED_error // XXX implement the command
+	.break
+
+#if CONFIG_MB_MEGA_65
+
+	// Command implementation for Mega65
+
+	// XXX provide implementation
+
+	jmp do_NOT_IMPLEMENTED_error
+
+#elif CONFIG_MB_ULTIMATE_64
+
+	// Command implementation for Ultimate 64
+
+	// Try to disable turbo in SuperCPU compatible way
+	sta SCPU_SPEED_NORMAL
+
+	jmp execute_statements
+
+#elif CONFIG_PLATFORM_COMMODORE_64
+
+	// Command implementation for generic C64 platform
+
+	// Try to disable turbo mode in C128 compatible way
+
+	lda #$00
+	sta VIC_CLKRATE
+
+	// Try to disable turbo in SuperCPU compatible way
+	sta SCPU_SPEED_NORMAL
+
+	jmp execute_statements
+
+#else
+
+	jmp do_NOT_IMPLEMENTED_error
+
+#endif