; Minimal GS/OS dispatcher stub at $E100A8. Native, M=0, X=0. ; Stack at entry: S+1=PCL, S+2=PCH, S+3=PBR, S+4..5=bank (=0), ; S+9=parm ptr low 16, S+10=high. We only use the low 16 (bank-0 ; parm blocks). Writes $42 to *parm and returns A=0. .text php ; save P pha ; save A (16-bit) lda 9, s ; A = parm ptr 16 sta 0xe4 ; DP $E4..$E5 ldy #0 ; X=0 here, so 3-byte encoding sep #0x20 ; M=8 for the 1-byte store .byte 0xa9, 0x42 ; lda #$42 (8-bit imm under M=8) sta (0xe4), y ; *parm = $42 rep #0x20 ; M=16 pla ; restore A plp lda #0 ; status = 0 rtl