#678

Mayhem (US) 09

Mayhem (US)

4.683 lines of code

RasterbarsRSTRMusicSIDScrollerSCRLSpritesSPRT

History

Group
Mayhem — United States, founded 1986

The ninth numbered intro from Mayhem, an American cracking group that operated from 1986 to March 1989. With over 100 documented releases on CSDb, Mayhem was a substantial operation supported by a network of at least six headquarter BBSes. The group's coder Stormbringer also served as NTSC fixer — a critical role for American groups distributing European software that required timing adjustments for NTSC hardware. No specific credits for this intro's code, music, or graphics have been identified. Mayhem holds a total of five entries in this collection — #493 Mayhem (US)-02, #487 Mayhem (US)-04, #472 Mayhem (US)-06, and #973 Mayhem (US)-10 — making it one of the better-represented American groups despite the absence of per-intro metadata.

Sources: CSDb Group · intros.c64.org

mayhem_us-09.asm 4.683 lines
// ============================================
// output - Part 1 of 2
// ============================================
// KickAssembler syntax
// Generated by Restore 64 v0.2.1 alpha build 298, 2026-04-11 21:35:56
// https://restore64.dev by datucker / Rabenauge
//
// Load address: $0800  End: $ffff  (63488 bytes)
// Crunched with Exomizer v2/v3 (with relocation) — depacked by emulation
// Packer entry: $0810 (via BASIC SYS 2064)
// Entry point:  $0800 (2048)
// IRQ handler:  $0ac1 (irq_0ac1)
// IRQ handler:  $086b (irq_086b)
// IRQ handler:  $ea86 (nmi_ea86)
// IRQ handler:  $3453 (irq_3453)
// IRQ handler:  $0a6b (irq_0a6b)
//
// Code: 3532 bytes, Data: 59956 bytes
// Labels: 521, Subroutines: 24
//
// Cross-references: all OK
// ============================================


// --- Region $0800-$0bf5 ---
.pc = $0800 "smc_0800"

smc_0800:
        jmp loc_0d10                                // !SMC: modified by $366a, $fdc5

// Referenced by: jsr from $0d1c, $e0d2
sub_0803: {
        sei
        lda #$c1
        ldx #$0a
        sta $0314
        stx $0315
        lda $d011
        and #$7f
        sta $d011
        lda #$1e
        sta $d012
        lda #$81
        sta $d019
        sta $d01a
        lda $dc0e
        and #$fe
        sta $dc0e
        lda #$01
        sta dat_0b74
        sta $0b75
        sta dat_0bf6
        sta $0c14
        lda #$02
        sta $0b76
        sta $0b77
        lda #$00
        sta $9c
        sta $9e
        jsr sub_0b04
        jsr sub_0b0d
        lda #$00
        tay
loop:
        sta $d990,y
        sta $d9e0,y
        iny
        cpy #$28
        bne loop
        jsr sub_0c3e
        lda #$35
        sta $01
        jsr $f000
        lda #$37
        sta $01
        cli
        rts
}
irq_086b: {
        lda $d019
        and #$01
        bne skip1
        jmp $0a60
skip1:
        nop
        nop
        nop
        nop
        nop
        nop
        lda #$01
        sta $d020
        sta $d021
        ldx #$08
        jsr sub_0b24
        nop
        lda #$00
        sta $d020
        sta $d021
        lda $d016
        and #$f0
        ora $9c
        sta $d016
        ldx dat_0bf6
        jsr sub_0bc4
        ldx #$2b
        jsr sub_0b24
        nop
        lda $0bf8
        sta $d020
        sta $d021
        ldx #$08
        jsr sub_0b24
        lda $0bf9
        sta $d020
        sta $d021
        ldx #$08
        jsr sub_0b24
        lda $0bfa
        sta $d020
        sta $d021
        ldx #$08
        jsr sub_0b24
        lda $0bfb
        sta $d020
        sta $d021
        ldx #$01
        nop
        nop
        nop
        nop
        nop
        nop
        lda $0bfc
        sta $d020
        sta $d021
        ldx #$08
        jsr sub_0b24
        lda $0bfd
        sta $d020
        sta $d021
        ldx #$08
        jsr sub_0b24
        lda $0bfe
        sta $d020
        sta $d021
        ldx #$08
        jsr sub_0b24
        lda $0bff
        sta $d020