even more startup tweaks

c64/kernal/interrupts/fce2.hw_entry_reset.s

@@ -1,43 +0,0 @@
-// Resources describing the C64 reset sequence:
-// https://www.c64-wiki.com/wiki/Reset_(Process)
-
-
-hw_entry_reset:
-
-	// The GPL program at https://github.com/Klaus2m5/6502_65C02_functional_tests/blob/master/6502_functional_test.a65
-	// uses the following initial reset sequence, affirmed by c64 PRG p269
-
-	cld // for CPUs might clear D flag - but it is possible this is called manually
-	ldx #$FF
-	txs
-	sei
-
-	// The following routine is based on reading the public KERNAL jumptable routine
-	// list, and making unimaginative assumptions about what should be done on reset.
-	// Also, https://codebase64.org/doku.php?id=base:assembling_your_own_cart_rom_image was used
-	// as it shows example startup sequence, to be followe by cartridge creators
-
-	// C64 PRG p269
-	jsr cartridge_check
-	bne !+
-	jmp (ICART_COLD_START)
-!:
-	// Initialising IO is obviously required. Also indicated by c64 prg p269.
-	jsr JIOINIT
-	
-	// Setting up the screen and testing ram is obviously required
-	// also affirmed by p269 of c64 prg
-	jsr JRAMTAS // called RANTAM on Codebase64 wiki
-	
-	// Resetting IO vectors is obviously required, if we want interrupts to run
-	// also affirmed by c64 prg p269
-	jsr JRESTOR
-
-	//  "Compute's Mapping the 64" p236
-	jsr JCINT
-
-	// What do we do when finished?  A C64 jumps into the BASIC ROM
-	cli // allow interrupts to happen
-
-	// c64 prg p269
-	jmp (IBASIC_COLD_START)

c64/kernal/interrupts/fce2.interop

@@ -1,5 +0,0 @@
-System reset routine has to be placed under it's original location due to 'SYS 64738' being extremaly popular to reset the C64,
-to the point it went into popular culture.
-
-https://twitter.com/hashtag/SYS64738?src=hash
-https://www.computerhope.com/jargon/s/sys64738.htm

c64/kernal/interrupts/fe66.default_brk_handler.s

@@ -5,6 +5,11 @@ default_brk_handler:
 
 	sei // disable IRQs, to be sure they won't interfere
 
+	ldx #$00
+	sta VIC_SCROLX // turn the display off - we want as little screen artifacts as possible
+
+	cld // make sure this dangerous flag is disabled
+
 	jsr JRESTOR
 	jsr JIOINIT
 	jsr cint_brk