programs/subasm-2.s


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; SuBAsm
; The Sux Bootstrapped Assembler.
;
; by mr b0nk 500 <b0nk@b0nk.xyz>


.org $A000
; String Constants.
prg_name:
	.byte "SuBAsm"
ver_txt:
	.byte ", version "
ver_num:
	.byte "0.1"

; Directives.
dir:
	.byte "org"
	.byte "byte"
	.byte "word"
	.byte "dword"
	.byte "qword"
tok:
	.byte '.'
	.byte '#'
	.byte '$'
	.byte '%'
	.byte '('
	.byte ')'
	.byte ','

mne:
	.byte "AAB"
	.byte "ABA"
	.byte "ADC"
	.byte "AND"
	.byte "ARB"
	.byte "ASR"
	.byte "BCC"
	.byte "BCS"
	.byte "BEQ"
	.byte "BNE"
	.byte "BNG"
	.byte "BPO"
	.byte "BRK"
	.byte "BVC"
	.byte "BVS"
	.byte "CAB"
	.byte "CLC"
	.byte "CLI"
	.byte "CLV"
	.byte "CMP"
	.byte "CPB"
	.byte "CPS"
	.byte "CPX"
	.byte "CPY"
	.byte "DAB"
	.byte "DEB"
	.byte "DEC"
	.byte "DEX"
	.byte "DEY"
	.byte "DIV"
	.byte "ENT"
	.byte "INB"
	.byte "INC"
	.byte "INX"
	.byte "INY"
	.byte "JMP"
	.byte "JSL"
	.byte "JSR"
	.byte "LDA"
	.byte "LDB"
	.byte "LDX"
	.byte "LDY"
	.byte "LLB"
	.byte "LRB"
	.byte "LSL"
	.byte "LSR"
	.byte "MAB"
	.byte "MUL"
	.byte "NOP"
	.byte "OAB"
	.byte "ORA"
	.byte "PHA"
	.byte "PHB"
	.byte "PHP"
	.byte "PHX"
	.byte "PHY"
	.byte "PLA"
	.byte "PLB"
	.byte "PLP"
	.byte "PLX"
	.byte "PLY"
	.byte "RLB"
	.byte "ROL"
	.byte "ROR"
	.byte "RRB"
	.byte "RTI"
	.byte "RTL"
	.byte "RTS"
	.byte "SAB"
	.byte "SBC"
	.byte "SEC"
	.byte "SEI"
	.byte "STA"
	.byte "STB"
	.byte "STT"
	.byte "STX"
	.byte "STY"
	.byte "TAB"
	.byte "TAX"
	.byte "TAY"
	.byte "TBA"
	.byte "TSX"
	.byte "TXA"
	.byte "TXS"
	.byte "TXY"
	.byte "TYA"
	.byte "TYX"
	.byte "WAI"
	.byte "XAB"
	.byte "XOR"

; Start of program code.
.org $8600
subasm:
	ldb #0
	lda.w #tok
	sta.q ptr2
	tba
	jsl chk_tok

	jsl chk_mne
chk_tok:
	phy #2
	txy
	lda (ptr6), y
	cmp (ptr2), y
	ply #2
	cpx #7
	beq tok_false
tok_true:
	inb
tok_false:
	stb f
tok_end:
	ldb #0
	rtl

chk_mne:
	ply #2