added panic screen, added versioning mechanism proposal

c64/kernal/assets/kernal_messages.s

@@ -5,68 +5,74 @@
 
 // Double underscore prevents labels from being passed to VICE (would confuse monitor)
 
-.label __MSG_KERNAL_SEARCHING_FOR = __kernal_message_searching_for - __kernal_messages_start
-.label __MSG_KERNAL_LOADING       = __kernal_message_loading       - __kernal_messages_start
-.label __MSG_KERNAL_VERIFYING     = __kernal_message_verifying     - __kernal_messages_start
-.label __MSG_KERNAL_SAVING        = __kernal_message_saving        - __kernal_messages_start
-.label __MSG_KERNAL_FROM_HEX      = __kernal_message_from_hex      - __kernal_messages_start
-.label __MSG_KERNAL_TO_HEX        = __kernal_message_to_hex        - __kernal_messages_start
+.label __MSG_KERNAL_SEARCHING_FOR      = __msg_kernalsearching_for      - __msg_kernal_first
+.label __MSG_KERNAL_LOADING            = __msg_kernalloading            - __msg_kernal_first
+.label __MSG_KERNAL_VERIFYING          = __msg_kernalverifying          - __msg_kernal_first
+.label __MSG_KERNAL_SAVING             = __msg_kernalsaving             - __msg_kernal_first
+.label __MSG_KERNAL_FROM_HEX           = __msg_kernalfrom_hex           - __msg_kernal_first
+.label __MSG_KERNAL_TO_HEX             = __msg_kernalto_hex             - __msg_kernal_first
 
-#if CONFIG_BANNER_PAL_NTSC
-.label __MSG_KERNAL_PAL           = __kernal_message_pal           - __kernal_messages_start
-.label __MSG_KERNAL_NTSC          = __kernal_message_ntsc          - __kernal_messages_start
+#if CONFIG_SHOW_PAL_NTSC
+.label __MSG_KERNAL_PAL                = __msg_kernalpal                - __msg_kernal_first
+.label __MSG_KERNAL_NTSC               = __msg_kernalntsc               - __msg_kernal_first
 #endif
 
-.label __MSG_KERNAL_PANIC         = __kernal_message_panic         - __kernal_messages_start
-.label __MSG_KERNAL_PANIC_VERSION = __kernal_message_panic_version - __kernal_messages_start
+#if CONFIG_PANIC_SCREEN
+.label __MSG_KERNAL_PANIC              = __msg_kernalpanic              - __msg_kernal_first
+.label __MSG_KERNAL_PANIC_ROM_MISMATCH = __msg_kernalpanic_rom_mismatch - __msg_kernal_first
+#endif
 
 
-__kernal_messages_start:
+__msg_kernal_first:
 
-__kernal_message_searching_for:
+__msg_kernalsearching_for:
 	.byte $0D
 	.text "SEARCHING FOR"
 	.byte $80 + $20 // end of string mark + space
 
-__kernal_message_loading:
+__msg_kernalloading:
 	.byte $0D
 	.text "LOADIN"
 	.byte $80 + $47 // end of string mark + 'G'
 
-__kernal_message_verifying:
+__msg_kernalverifying:
 	.byte $0D
 	.text "VERIFYIN"
 	.byte $80 + $47 // end of string mark + 'G'
 
-__kernal_message_saving:
+__msg_kernalsaving:
 	.byte $0D
 	.text "SAVIN"
 	.byte $80 + $47 // end of string mark + 'G'
 
-__kernal_message_from_hex:
+__msg_kernalfrom_hex:
 	.text " FROM "
 	.byte $80 + $24 // end of string mark + '$'
 
-__kernal_message_to_hex:
+__msg_kernalto_hex:
 	.text " TO "
 	.byte $80 + $24 // end of string mark + '$'
 
-#if CONFIG_BANNER_PAL_NTSC
+#if CONFIG_SHOW_PAL_NTSC
 
-__kernal_message_pal:
-	.text ", PAL"
+__msg_kernalpal:
+	.text "PAL,"
 	.byte $80 + $20 // end of string mark + space
 
-__kernal_message_ntsc:
-	.text ", NTSC"
+__msg_kernalntsc:
+	.text "NTSC,"
 	.byte $80 + $20 // end of string mark + space
 
-#endif // CONFIG_BANNER_PAL_NTSC
+#endif // CONFIG_SHOW_PAL_NTSC
 
-__kernal_message_panic:
+#if CONFIG_PANIC_SCREEN
+
+__msg_kernalpanic:
 	.text "KERNAL PANI"
 	.byte $80 + $43 // end of string mark + 'C'
 
-__kernal_message_panic_version:
+__msg_kernalpanic_rom_mismatch:
 	.text " - ROM MISMATC"
 	.byte $80 + $48 // end of string mark + 'H'
+
+#endif // CONFIG_PANIC_SCREEN

c64/kernal/chkinout_real.s

@@ -5,7 +5,7 @@
 // - [RG64] C64 Programmer's Reference Guide   - page 275 (CHKIN) / 276 (CKOUT)
 // - [CM64] Compute's Mapping the Commodore 64 - page 229
 //
-// CPU registers that has to be preserved (see [RG64]): .Y
+// CPU registers that has to be preserved (see [RG64]): .Y, possibly .A (XXX - see [CM64], page 213)
 //
 
 

c64/kernal/panic.s

@@ -3,19 +3,29 @@
 // Something terrible happened - show the panic screen
 //
 
-// .A = 0 - just panic, no extra message
-// .A = 1 - ROM version mismatch
+
+#if CONFIG_PANIC_SCREEN
 
 panic:
 
+	// Disable interrupts, store error code on stack
+
 	sei
 	pha
 
+	// Reinitialize the hardware
+
 	jsr IOINIT
 	jsr setup_vicii
 	jsr clear_screen
 
-	// XXX disable NMIs
+	// Disable NMIs - our routine checks for NULL vector
+
+	lda #$00
+	sta NMINV+0
+	sta NMINV+1
+
+	// Display KERNAL PANIC message
 
 	ldx #$14
 	ldy #$0E
@@ -24,6 +34,8 @@ panic:
 	ldx #__MSG_KERNAL_PANIC
 	jsr print_kernal_message
 
+	// Display error code and message (if known)
+
 	pla
 	beq kernal_panic_infinite_loop
 	pha
@@ -37,12 +49,14 @@ panic:
 	jsr print_hex_byte
 
 	pla
-	cmp #$01
+	cmp #P_ERR_ROM_MISMATCH
 	bne kernal_panic_infinite_loop
 
-	ldx #__MSG_KERNAL_PANIC_VERSION
+	ldx #__MSG_KERNAL_PANIC_ROM_MISMATCH
 	jsr print_kernal_message
 
+	// Display some raster effect in the infinitew loop
+
 kernal_panic_infinite_loop:
 	ldx #$00
 	stx VIC_EXTCOL
@@ -59,3 +73,5 @@ kernal_panic_infinite_loop:
 	bne !-
 
 	beq kernal_panic_infinite_loop // branch always
+
+#endif // CONFIG_PANIC_SCREEN

c64/kernal/print/print_kernal_message.s

@@ -9,7 +9,7 @@
 
 print_kernal_message:
 
-	lda __kernal_messages_start, x
+	lda __msg_kernal_first, x
 	bpl !- // 0 marks end of string
 	and #$7F
 	jmp JCHROUT

c64/kernal/print/print_pal_ntsc.s

@@ -3,7 +3,7 @@
 // Print video system on startup banner
 //
 
-#if CONFIG_BANNER_PAL_NTSC
+#if CONFIG_SHOW_PAL_NTSC
 
 print_pal_ntsc:
 
@@ -14,4 +14,4 @@ print_pal_ntsc:
 !:
 	jmp print_kernal_message
 
-#endif // CONFIG_BANNER_PAL_NTSC
+#endif // CONFIG_SHOW_PAL_NTSC

c64/kernal/xxxx.rom_revision_kernal.s

@@ -1,34 +0,0 @@
-
-//
-// !!! PROPOSAL ONLY !!! PROPOSAL ONLY !!! NOT FOR USING EXTERNALLY YET !!!
-//
-//
-// Do not change! Locations of the following data should be constant - now and forever!
-//
-// If you want to integrate Open ROMs support in your emulator, FPGA ccomputer, etc. - this
-// is the official way to recognize the ROM and it's revision.
-//
-
-
-// XXX we need to find a safe address within $E4D3-$FFFF range, we need 20 bytes
-
-
-panic_vector: 
-
-	// This vector is to be used by non-Kernal ROMs, if they want to complain
-	// about incompatible ROM releases - jump via this vector with .A set to 1
-
-	.byte <panic
-	.byte >panic
-
-rom_revision_kernal:
-
-	.text "OR"               // Magic string, after "Open ROMs"
-	.byte CONFIG_ID          // Config file ID, might change between revisions
-
-rom_revision_kernal_string:
-
-	.text "DEVEL SNAPSHOT"   // Actual ROM revision string
-	.byte $00
-
-__rom_revision_kernal_end: