ASSEMBLE.TXT

DECLARE FUNCTION StringCompare% (s$, t$, n$)
DECLARE SUB SpecialInstruction ()   'yet more left
DECLARE FUNCTION Register% (s$)
DECLARE FUNCTION Memory% (s$)
DECLARE FUNCTION Immediate% (s$)
DECLARE SUB GetMnemonic ()
DECLARE FUNCTION PartDetermine% (s$)
DECLARE SUB PartModify ()
DECLARE SUB FindStyle ()
DECLARE SUB LoadOpcodeList ()
DECLARE SUB MatchOpcode ()
DECLARE SUB GenerateOpcode (p&)
DECLARE SUB ErrorHandler ()
DECLARE SUB FindSingleOp ()
DECLARE SUB zPostProcessor (assemblyline$)
DECLARE FUNCTION ShowHex$ (s$)

CONST REG = 0, MEM = 1, IMM = 2, NON = 3

DIM SHARED Mnemonic$, Opcode$, Part1$, Part2$, Parts1%, Parts2%
DIM SHARED RegisterInf%, MemoryInf%, MemoryData%
DIM SHARED Immediate1Inf%, Immediate1Data%, Immediate2Inf%, Immediate2Data%
DIM SHARED Dir%, Signex%, Word%, Check1%, Check2%, Errors%
DIM SHARED Registers$, Memories$, ReletedData%, MachineCode$, PostInitialize%
Mnemonic$ = ""
Opcode$ = ""
Part1$ = ""
Part2$ = ""
Parts1% = 0
Parts2% = 0
Dir% = 0
Signex% = 0
Word% = 0
Errors% = 0
RelatedData% = 0
DIM SHARED Op%(4)
DIM SHARED OpcodeTable(0) AS STRING * 32764
DIM SHARED TableSeg&, TableOff&, TableOffU&, TableEnd&
Registers$ = "AXBXCXDXSPBPSIDIALBLCLDLAHBHCHDHESCSSS      DS  "
Memories$ = "[BX+SI]     [BX+DI]     [BP+SI]     [BP+DI]     "
Memories$ = Memories$ + "[SI]        [DI]        [****]      [BX]        "
Memories$ = Memories$ + "[BX+SI+**]  [BX+DI+**]  [BP+SI+**]  [BP+DI+**]  "
Memories$ = Memories$ + "[SI+**]     [DI+**]     [BP+**]     [BX+**]     "
Memories$ = Memories$ + "[BX+SI+****][BX+DI+****][BP+SI+****][BP+DI+****]"
Memories$ = Memories$ + "[SI+****]   [DI+****]   [BP+****]   [BX+****]   "
TableSeg& = VARSEG(OpcodeTable(0))
TableOff& = VARPTR(OpcodeTable(0)) 'start of fixed type opcodes
TableOffU& = TableOff& + 23        'start of unfixed type opcodes
TableEnd& = TableOff& + 32764

'Testing
DEF SEG = TableSeg&
POKE 0, ASC("C")
POKE 1, ASC("L")
POKE 2, ASC("D")
POKE 3, 32
POKE 4, 32
POKE 5, &HFF
POKE 6, ASC("E")
POKE 7, ASC("S")
POKE 8, ASC(":")
POKE 9, 32
POKE 10, 32
POKE 11, &HFE
DEF SEG
zPostProcessor "OUT DX,AL"

SUB ErrorHandler

END SUB

SUB FindSingleOp
'Start to read the table
DEF SEG = TableSeg&
p& = TableOff&    'begining of table
'Opcode name match
DO
IF (PEEK(p&) = Op%(0) AND PEEK(p& + 1) = Op%(1) AND PEEK(p& + 2) = Op%(2) AND PEEK(p& + 3) = Op%(3) AND PEEK(p& + 4) = Op%(4)) THEN
MachineCode$ = CHR$(PEEK(p& + 5))
EXIT DO
END IF
p& = p& + 6
LOOP UNTIL p& < TableOff&
DEF SEG
END SUB

SUB FindStyle
Dir% = 1    'default value
Signex% = 0
Parts1% = PartDetermine%(Part1$)
Parts2% = PartDetermine%(Part2$)

'Error detection in parts and setting flags
PartModify

'Generate opcode list match bytes
Check2% = 0
Check1% = (Parts1% * &H40) OR (Parts2% * &H10)
IF (Parts1% = REG) THEN Check2% = (RegisterInf% \ &H20) AND 1
IF (Parts1% = IMM) THEN Check2% = Word% + 1

END SUB

SUB GenerateOpcode (p&)
'Opcode Style
'Byte style
'ppqqrrt0 ddwwxxxx cccccccc cccccccc
'pp = part1  qq = part2  rr = part1pos  t = part1switch   o = opcodesize
'PartDEF     s
'00=Reg  01=Mem  10=Imm  11=Non
'tDEF
'Reg-Reg/Seg  Mem-?  Imm-?/byte/word/any  Non-?
'oDEF
'specified in xxxx

'Get Opcode
Cd$ = ""
CdSeg& = VARSEG(Cd$)
CdOff& = SADD(Cd$)
DEF SEG = TableSeg&

'Write opcode byte
b% = PEEK(p& + 1) AND &HF
FOR i& = 0 TO b%
Cd$ = Cd$ + CHR$(PEEK(p& + 2 + i&))
NEXT

'Set ds bit
b% = PEEK(p& + 1) \ &H40
IF (b% = 0) THEN GOTO dsbite
IF (b% = 1) THEN b% = Dir% ELSE b% = Signex%
DEF SEG = CdSeg&
POKE CdOff&, PEEK(CdOff&) OR (b% * 2)
DEF SEG = TableSeg&
dsbite:

     
'Set word bit
b% = (PEEK(p& + 1) \ &H10) AND 3
IF (b% = 0) THEN GOTO wbite
DEF SEG = CdSeg&
IF (b% = 1) THEN
POKE CdOff&, PEEK(CdOff&) OR Word%
ELSE
POKE CdOff&, PEEK(CdOff&) OR (Word% * 8)
END IF
DEF SEG = TableSeg&
wbite:

'Set reg field
b% = (PEEK(p&) \ 4) AND 3
IF (b% = 0) THEN GOTO regfielde
DEF SEG = CdSeg&
IF (b% = 1) THEN POKE CdOff&, PEEK(CdOff&) OR (RegisterInf% AND 7)
IF (b% = 2) THEN POKE CdOff&, PEEK(CdOff&) OR ((RegisterInf% AND 7) * 8)
IF (b% = 3) THEN POKE CdOff& + 1, PEEK(CdOff& + 1) OR ((RegisterInf% AND 7) * 8)
DEF SEG = TableSeg&
regfielde:

'Set md r/m field
IF (Parts2% = MEM OR Parts2% = REG) THEN
b% = (MemoryInf% AND 7) OR ((MemoryInf% AND &H30) * 4)
DEF SEG = CdSeg&
IF (b% = 1) THEN POKE CdOff& + 1, PEEK(CdOff& + 1) OR b%
IF (b% = 2) THEN POKE CdOff& + 1, PEEK(CdOff& + 1) OR b%
IF (b% = 3) THEN POKE CdOff& + 1, PEEK(CdOff& + 1) OR b%
IF ((MemoryInf% AND &H30 = &H10) OR (MemoryInf% AND &H30 = &H20)) THEN Cd$ = Cd$ + MKI$(MemoryData%)
DEF SEG = TableSeg&
END IF

'Write Immediate data
IF (Parts1% = IMM OR (Parts1% <> IMM AND Parts2% = IMM)) THEN
Cd$ = Cd$ + LEFT$(MKI$(Immediate1Data%), Word% + 1)
IF (Parts1% = IMM AND Parts2% = IMM) THEN Cd$ = Cd$ + MKI$(Immediate2Data%)
END IF

MachineCode$ = Cd$
'All over.
END SUB

SUB GetMnemonic
SpecialInstruction
Part1$ = ""
Part2$ = ""
v% = INSTR(Mnemonic$, " ")
IF (v% <= 0) THEN v% = LEN(Mnemonic$) + 1: opend% = 1
Opcode$ = MID$(Mnemonic$, 1, v% - 1)
Opcode$ = Opcode$ + SPACE$(5 - LEN(Opcode$))
IF (opend% = 1) THEN GOTO getmne
v2% = INSTR(v% + 1, Mnemonic$, ",")
IF (v% <= 0) THEN v% = LEN(Mnemonic$) + 1: opend% = 1
Part1$ = MID$(Mnemonic$, v% + 1, v2% - v% - 1)
IF (opend% = 1) THEN GOTO getmne
Part2$ = MID$(Mnemonic$, v2% + 1, LEN(Mnemonic$) - v2%)
getmne:

'Create Op%(array) that contains Opcode in ASCII
FOR i% = 1 TO 5
Op%(i% - 1) = ASC(MID$(Opcode$, i%, 1))
NEXT

END SUB

FUNCTION Immediate% (s$)
a% = -1
IF (LEN(s$) > 4 OR LEN(s$) = 0) THEN GOTO imm0
FOR i% = 1 TO LEN(s$)
b% = ASC(MID$(s$, i%, 1))
IF (b% >= 65 AND b% <= 70) THEN
c& = c& * &H10 + (b% - 55)
ELSEIF (b% >= 48 AND b% <= 57) THEN c& = c& * &H10 + (b% - 48)
ELSE GOTO imm0
END IF
NEXT
IF (c& > &H7FFF) THEN c& = c& - 65536
RelatedData% = CINT(c&)
IF (LEN(s$) > 2) THEN
a% = a% OR &H10
b% = SGN(a%)
IF (b% = 1) THEN b% = 0
IF ((c& \ &H100) = b%) THEN a% = a% OR &H20
END IF
imm0:
Immediate% = a%
'Immediate = 00sw 0000 [data]
END FUNCTION

SUB LoadOpcodeList
'Opcode Style
'Byte style
'ppqqrrt0 ddwwxxxx cccccccc cccccccc
'pp = part1  qq = part2  rr = part1pos  t = part1switch   o = opcodesize
'PartDEF     s
'00=Reg  01=Mem  10=Imm  11=Non
'tDEF
'Reg-Reg/Seg  Mem-?  Imm-?/byte/word/any  Non-?
'oDEF
'specified in xxxx

'ppqq0000
'000000t0
fr% = FREEFILE
OPEN "B", #fr%, "Table.dat"
GET #fr%, 1, OpcodeTable(0)
CLOSE #fr%
PostInitialize% = 1
END SUB

SUB MatchOpcode
'Start to read the table
DEF SEG = TableSeg&
p& = TableOffU&

'Opcode name match
DO
IF (PEEK(p&) = Op%(0) AND PEEK(p& + 1) = Op%(1) AND PEEK(p& + 2) = Op%(2) AND PEEK(p& + 3) = Op%(3) AND PEEK(p& + 4) = Op%(4)) THEN
v% = PEEK(p& + 5)  'first information byte
w% = PEEK(p& + 6)  'second information byte
IF (v% AND Check1% = Check1%) THEN   'Opcode Check1 match
IF (Parts1% = REG) THEN              'Opcode Check2 match
IF (v% AND Check2% = Check2%) THEN GOTO Opcodefound
ELSEIF ((Parts1% = IMM) AND (w% AND &H30 = 0)) THEN
IF (v% AND Check2% = Check2%) THEN GOTO Opcodefound
ELSE
GOTO Opcodefound
END IF
END IF
END IF
p& = p& + (w% AND 16) + 7
LOOP UNTIL (p& > TableEnd&)
Errors% = 0 'opcode not found
GOTO mtche
Opcodefound:
GenerateOpcode (p&)
mtche:
END SUB

FUNCTION Memory% (s$)
a% = -1
IF (LEN(s$) > 12) THEN GOTO mem0
t$ = s$ + SPACE$(12 - LEN(s$))
FOR i% = 1 TO LEN(Memories$) STEP 12
IF StringCompare%(t$, MID$(Memories$, i%, 12), "*") THEN
v% = INSTR(i%, Memories$, "*")
IF (v% <= 0) THEN
c% = 0
ELSEIF (MID$(Memories$, v%, 4) = "****") THEN
d% = Immediate%(MID$(s$, 1 + v% - i%, 4))
c% = RelatedData%
ELSE
d% = Immediate%(MID$(s$, 1 + v% - i%, 2))
c% = RelatedData%
END IF
b% = (i% - 1) \ 12
a% = ((b% \ 8) * &H10) OR (b% AND 7)
GOTO mem0
END IF
NEXT
a% = -1
mem0:
Memory% = a%
RelatedData% = c%
'Memory = 01md 0r/m
END FUNCTION

FUNCTION PartDetermine% (s$)
'See if register
a% = Register%(s$)
IF (a% <> -1) THEN
IF (RegisterInf% = 0) THEN RegisterInf% = a% ELSE MemoryInf% = a%
a% = REG
GOTO prtdtr
END IF
'See if memory
a% = Memory%(s$)
IF (a% <> -1) THEN
MemoryInf% = a%
a% = MEM
MemoryData% = RelatedData%
GOTO prtdtr
END IF
'See if immediate
a% = Immediate%(s$)
IF (a% <> -1) THEN
IF (Immediate1Inf% = 0) THEN
Immediate1Inf% = a%
Immediate1Data% = RelatedData%
ELSE
Immediate2Inf% = a%
Immediate2Data% = RelatedData%
END IF
a% = IMM
END IF
'It is none.
a% = NON
prtdtr:
PartDetermine% = a%
END FUNCTION

SUB PartModify

'not,else
IF (Parts1% = NON AND Parts2% <> NON) THEN Errors% = 0
'imm,reg
IF (Parts1% = IMM AND Parts2% = REG) THEN Errors% = 0
'imm,mem
IF (Parts1% = IMM AND Parts2% = MEM) THEN Errors% = 0
'mem,mem
IF (Parts1% = MEM AND Parts2% = MEM) THEN Errors% = 0

'Set reg,reg to reg,mem(3)
IF (Parts1% = REG AND Parts2% = REG) THEN  'reg,reg
IF (MemoryInf% AND &H20 = &H20) THEN SWAP RegisterInf%, MemoryInf%: Dir% = 0 'reg,seg
Wcheck% = (MemoryInf% \ &H10) AND 1
MemoryInf% = MemoryInf% AND &H70
END IF

'Set mem,reg to reg,mem
IF (Parts1% = MEM AND Parts2% = REG) THEN Dir% = 0

'Set mem,imm
IF (Parts1% = MEM AND Parts2% = IMM) THEN   'mem
Word% = (Immediate1Inf% \ &H10) AND 1
GOTO nosetword
END IF

IF (Parts2% = IMM) THEN Wcheck% = (Immediate2Inf% \ &H10) AND 1

'Setting flags
'Set Word
IF (Parts1% = REG) THEN Word% = (RegisterInf% \ &H10) AND 1
IF (Parts1% = IMM) THEN Word% = (Immediate1Inf% \ &H10) AND 1
IF (Word% <> Wcheck%) THEN Errors% = 0   'unmatch

nosetword:
'Set Signex
IF (Parts1% = IMM OR Parts2% = IMM) THEN Signex% = (Immediate1Inf% \ &H20) AND 1

END SUB

FUNCTION Register% (s$)
a% = -1
IF (LEN(s$) <> 2) THEN GOTO reg0
'It maybe a register
FOR i% = 1 TO LEN(Registers$) STEP 2
IF (MID$(Registers$, i%, 2) = s$) THEN
b% = (i% - 1) \ 2
IF (b% >= 16) THEN
a% = &H30
ELSEIF (b% < 8) THEN a% = &H10
END IF
a% = a% OR (b% AND 7)
GOTO reg0
END IF
NEXT
a% = -1
reg0:
Register% = a%
'Register = 00sw 0rrr
END FUNCTION

FUNCTION ShowHex$ (s$)
FOR i% = 1 TO LEN(s$)
a$ = a$ + HEX$(ASC(MID$(s$, i%, 1)))
NEXT
ShowHex$ = a$
END FUNCTION

SUB SpecialInstruction
IF StringCompare%(Mnemonic$, "OUT DX,AL", "") THEN
Mnemonic$ = "OUTDB"
ELSEIF StringCompare%(Mnemonic$, "OUT DX,AX", "") THEN Mnemonic$ = "OUTDW"
ELSEIF StringCompare%(Mnemonic$, "OUT **,AL", "*") THEN Mnemonic$ = "OUTB " + MID$(Mnemonic$, 5, 2)
ELSEIF StringCompare%(Mnemonic$, "OUT **,AX", "*") THEN Mnemonic$ = "OUTW " + MID$(Mnemonic$, 5, 2)
ELSEIF StringCompare%(Mnemonic$, "IN AL,DX", "") THEN Mnemonic$ = "INDB"
ELSEIF StringCompare%(Mnemonic$, "IN AX,DX", "") THEN Mnemonic$ = "INDW"
ELSEIF StringCompare%(menmonic$, "IN AL,**", "*") THEN Mnemonic$ = "INDB " + MID$(Mnemonic$, 7, 2)
ELSEIF StringCompare%(Mnemonic$, "IN AX,**", "*") THEN Mnemonic$ = "INDW " + MID$(Mnemonic$, 7, 2)
ELSEIF StringCompare%(Mnemonic$, "SHL **,1", "*") THEN Mnemonic$ = "SHL1 " + MID$(Mnemonic$, 5, 2)
ELSEIF StringCompare%(Mnemonic$, "SHL **,CL", "*") THEN Mnemonic$ = "SHLC " + MID$(Mnemonic$, 5, 2)
ELSEIF StringCompare%(Mnemonic$, "SHR **,1", "*") THEN Mnemonic$ = "SHR1 " + MID$(Mnemonic$, 5, 2)
ELSEIF StringCompare%(Mnemonic$, "SHR **,CL", "*") THEN Mnemonic$ = "SHRC " + MID$(Mnemonic$, 5, 2)
ELSEIF StringCompare%(Mnemonic$, "SAR **,1", "*") THEN Mnemonic$ = "SAR1 " + MID$(Mnemonic$, 5, 2)
ELSEIF StringCompare%(Mnemonic$, "SAR **,CL", "*") THEN Mnemonic$ = "SARC " + MID$(Mnemonic$, 5, 2)
ELSEIF StringCompare%(Mnemonic$, "ROL **,1", "*") THEN Mnemonic$ = "ROL1 " + MID$(Mnemonic$, 5, 2)
ELSEIF StringCompare%(Mnemonic$, "ROL **,CL", "*") THEN Mnemonic$ = "ROLC " + MID$(Mnemonic$, 5, 2)
ELSEIF StringCompare%(Mnemonic$, "ROR **,1", "*") THEN Mnemonic$ = "ROR1 " + MID$(Mnemonic$, 5, 2)
ELSEIF StringCompare%(Mnemonic$, "ROR **,CL", "*") THEN Mnemonic$ = "RORC " + MID$(Mnemonic$, 5, 2)
ELSEIF StringCompare%(Mnemonic$, "RCL **,1", "*") THEN Mnemonic$ = "RCL1 " + MID$(Mnemonic$, 5, 2)
ELSEIF StringCompare%(Mnemonic$, "RCL **,CL", "*") THEN Mnemonic$ = "RCLC " + MID$(Mnemonic$, 5, 2)
ELSEIF StringCompare%(Mnemonic$, "RCR **,1", "*") THEN Mnemonic$ = "SHL1 " + MID$(Mnemonic$, 5, 2)
ELSEIF StringCompare%(Mnemonic$, "RCR **,CL", "*") THEN Mnemonic$ = "SHLC " + MID$(Mnemonic$, 5, 2)
ELSEIF (Part1$ = "AX" OR Part1$ = "AL") THEN
Mnemo
'jmp xxxx:xxxx = jmp xxxx,xxxx
END IF
END SUB

FUNCTION StringCompare% (s$, t$, n$)
IF (n$ = "") THEN a% = (s$ = t$): GOTO strcmp0
IF (LEN(s$) <> LEN(t$)) THEN GOTO strcmp0
FOR i% = 1 TO LEN(s$)
a$ = MID$(t$, i%, 1)
IF (a$ <> n$ AND a$ <> MID$(s$, i%, 1)) THEN GOTO strcmp0
NEXT
a% = -1
strcmp0:
StringCompare% = a%
END FUNCTION

SUB zPostProcessor (assemblyline$)
IF (PostInitialize% = 0) THEN LoadOpcodeList
MachineCode$ = ""
Mnemonic$ = UCASE$(assemblyline$)
GetMnemonic
SpecialInstruction
GetMnemonic
FindSingleOp
IF (MachineCode$ = "") THEN
FindStyle
MatchOpcode
END IF
PRINT "Machine code:" + ShowHex$(MachineCode$)
END SUB