873 lines
16 KiB
NASM
873 lines
16 KiB
NASM
keep obj/pass1
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mcopy pass1.mac
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****************************************************************
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*
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* Pass 1
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*
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* This module contains the subroutines used to do pass 1
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* processing of the input files.
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*
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****************************************************************
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copy directPage
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****************************************************************
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*
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* Align - align the code to a byte boundary
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*
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* Inputs:
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* sp - pointer to the opcode
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* pc - current program counter
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*
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* Outputs:
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* sp - pointer to the next opcode
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* pc - new program counter
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*
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****************************************************************
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*
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Align private
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ldy #1 get the alignment factor
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lda [sp],Y
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sta r0
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iny
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iny
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lda [sp],Y
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sta r2
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add4 sp,#5
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jsr PrepareAlign do pass 1 prep for the align
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rts
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end
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****************************************************************
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*
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* Const - constant bytes
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*
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* Inputs:
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* sp - pointer to the opcode
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* pc - current program counter
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*
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* Outputs:
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* sp - pointer to the next opcode
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* pc - new program counter
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*
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****************************************************************
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*
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Const private
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lda [sp]
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and #$00FF
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tax
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clc
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adc pc
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sta pc
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bcc lb1
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inc pc+2
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lb1 txa
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sec
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adc sp
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sta sp
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bcc lb2
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inc sp+2
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lb2 rts
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end
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****************************************************************
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*
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* DefineSegment - put the segment in the symbol table
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*
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* Inputs:
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* segName - pointer to the segment name
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* segType - segment type
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* pc - current pc
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* segEntry - disp to segment entry point
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*
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****************************************************************
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*
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DefineSegment private
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using Common
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ph4 segName push the symbol name ptr
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ph2 #0 length attribute is 0
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ph2 #'N' push the type attribute
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lda segType push the private flag
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and #$4000
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beq lb1
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lda #1
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lb1 pha
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ph2 #1 the symbol is global
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ph2 #0 the symbol is not an expression
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clc push the location
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lda pc
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adc segEntry
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tax
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lda pc+2
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adc segEntry+2
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pha
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phx
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lda segType push the data area flag
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and #$007F
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cmp #1
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beq lb2
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ph2 #0
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bra lb3
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lb2 ph2 #1
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lb3 ph2 #1 push the segment flag
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jsr Define define the symbol
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rts
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end
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****************************************************************
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*
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* DoOrg - set the program counter
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*
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* Inputs:
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* sp - pointer to the opcode
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* pc - current program counter
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*
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* Outputs:
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* sp - pointer to the next opcode
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* pc - new program counter
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*
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****************************************************************
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*
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DoOrg private
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using OutCommon
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ldy #1 get the value and skip the record
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lda [sp],Y
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sta r0
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ldy #3
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lda [sp],Y
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sta r2
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add4 sp,#5
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lda r2
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bmi lb1 if the disp is positive
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add4 pc,r0 update the pc
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lb1 anop
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rts
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end
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****************************************************************
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*
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* DoPass1 - Do pass 1 processing
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*
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* Outputs:
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* C - set if an error occurred
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*
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****************************************************************
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*
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DoPass1 start
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using Common
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;
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; Write the pass header
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;
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lda #1 pass = 1
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sta pass
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lda list if list then
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beq wp1
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puts #'Segment:',cr=t print the general header
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putcr
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bra wp2 else if progress then
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wp1 lda progress
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beq wp2
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puts #'Pass 1: ' print the dot header
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wp2 anop
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;
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; Initialize pass dependent variables
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;
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jsr InitPass
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;
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; Process segments until there are no more
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;
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ps1 jsr NextSegment get the next segment
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bcc rt1 branch if there are no more
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jsr DefineSegment put the segment in the symbol table
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jsr ListSeg list the segname start info
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jsr DoSegment process this segment
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add4 pc,segSpace add in the reserved space (if any)
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bra ps1 next segment
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;
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; Return to main
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;
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rt1 lda list if list or progress then
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bne rt2
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lda progress
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beq rt3
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rt2 putcr write a cr
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rt3 anop endif
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clc
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rts
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end
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****************************************************************
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*
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* DoSegment - process the opcodes in this segment
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*
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* Inputs:
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* sp - pointer to the first opcode to process
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*
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****************************************************************
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*
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DoSegment private
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lb1 lda [sp]
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and #$00FF
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asl A
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tax
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jsr (addr,X)
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bra lb1
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addr dc a'End' $00 End
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dc 15a'Const' $01..$0F Const
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dc 16a'Const' $10..$1F Const
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dc 16a'Const' $20..$2F Const
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dc 16a'Const' $30..$3F Const
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dc 16a'Const' $40..$4F Const
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dc 16a'Const' $50..$5F Const
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dc 16a'Const' $60..$6F Const
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dc 16a'Const' $70..$7F Const
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dc 16a'Const' $80..$8F Const
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dc 16a'Const' $90..$9F Const
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dc 16a'Const' $A0..$AF Const
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dc 16a'Const' $B0..$BF Const
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dc 16a'Const' $C0..$CF Const
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dc 16a'Const' $D0..$DF Const
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dc a'Align' $E0 Align
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dc a'DoOrg' $E1 Org
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dc a'Invalid' $E2 Reloc
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dc a'Invalid' $E3 Interseg
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dc a'Strong' $E4 Using
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dc a'Strong' $E5 Strong
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dc a'Global' $E6 Global
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dc a'Gequ' $E7 Gequ
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dc a'Invalid' $E8 Mem
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dc a'Invalid' $E9 unused
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dc a'Invalid' $EA unused
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dc a'Expr' $EB Expr
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dc a'Expr' $EC ZExpr
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dc a'Expr' $ED BExpr
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dc a'RelExpr' $EE RelExpr
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dc a'Local' $EF Local
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dc a'Equ' $F0 Equ
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dc a'DS' $F1 DS
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dc a'Lconst' $F2 LConst
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dc a'Expr' $F3 LExpr
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dc a'Invalid' $F4 Entry
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dc a'Invalid' $F5 cReloc
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dc a'Invalid' $F6 cInterseg
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dc a'Invalid' $F7 Super
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dc a'Invalid' $F8 unused
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dc a'Invalid' $F9 unused
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dc a'Invalid' $FA unused
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dc a'Invalid' $FB unused
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dc a'Invalid' $FC unused
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dc a'Invalid' $FD unused
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dc a'Invalid' $FE unused
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dc a'Invalid' $FF unused
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end
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****************************************************************
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*
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* DS - insert zeros at the PC
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*
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* Inputs:
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* sp - pointer to the opcode
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* pc - current program counter
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*
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* Outputs:
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* sp - pointer to the next opcode
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* pc - new program counter
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*
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****************************************************************
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*
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DS private
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inc4 sp
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ldy #2
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clc
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lda [sp]
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adc pc
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sta pc
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lda [sp],Y
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adc pc+2
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sta pc+2
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add4 sp,#4
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rts
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end
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****************************************************************
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*
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* End - end of the segment
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*
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****************************************************************
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*
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End private
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pla
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rts
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end
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****************************************************************
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*
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* EndExp - end of the expression
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*
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* Inputs:
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* sp - pointer to the opcode
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*
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* Outputs:
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* sp - pointer to the next opcode
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*
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****************************************************************
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*
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EndExp private
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inc4 sp
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pla
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rts
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end
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****************************************************************
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*
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* Equ - define a local equate
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*
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* Inputs:
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* sp - pointer to the opcode
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*
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* Outputs:
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* sp - pointer to the next opcode
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*
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****************************************************************
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*
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Equ private
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using Common
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inc4 sp skip the op code
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ph4 sp push the symbol name ptr
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lda [sp] skip the symbol name
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and #$00FF
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sec
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adc sp
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sta sp
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bcc lb1
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inc sp+2
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lb1 lda segVersion if the segment is version 0 or 1 then
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cmp #2
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beq lb2
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lda [sp] push the length byte
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and #$00FF
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pha
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inc4 sp ++sp
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bra lb3 else
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lb2 lda [sp] push the length word
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pha
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add4 sp,#2 sp += 2
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lb3 anop endif
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lda [sp] push the type attribute
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and #$00FF
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pha
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lda [sp] push the private flag
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and #$FF00
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xba
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pha
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add4 sp,#2 sp += 2 {skip the attributes}
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ph2 #0 the symbol is local
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ph2 #1 the symbol is an expression
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ph4 sp push the address of the expression
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ph2 #0 push the data area flag
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ph2 #0 push the segment flag
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jsr Define define the symbol
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jsr SkipExpression skip the expression
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rts
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end
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****************************************************************
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*
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* Expr - evaluate an expression
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*
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* Inputs:
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* sp - pointer to the opcode
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* pc - current program counter
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*
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* Outputs:
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* sp - pointer to the next opcode
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* pc - new program counter
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*
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****************************************************************
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*
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Expr private
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lda [sp] update the PC
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xba
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and #$00FF
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clc
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adc pc
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sta pc
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bcc lb1
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inc pc+2
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lb1 add4 sp,#2 skip the op code and expression length
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brl SkipExpression skip the expression
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end
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****************************************************************
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*
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* Gequ - define a global equate
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*
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* Inputs:
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* sp - pointer to the opcode
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*
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* Outputs:
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* sp - pointer to the next opcode
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*
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****************************************************************
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*
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Gequ private
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using Common
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inc4 sp skip the op code
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ph4 sp push the symbol name ptr
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lda [sp] skip the symbol name
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and #$00FF
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sec
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adc sp
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sta sp
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bcc lb1
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inc sp+2
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lb1 lda segVersion if the segment is version 0 ro 1 then
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cmp #2
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beq lb2
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lda [sp] push the length byte
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and #$00FF
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pha
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inc4 sp ++sp
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bra lb3 else
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lb2 lda [sp] push the length word
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pha
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add4 sp,#2 sp += 2
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lb3 anop endif
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lda [sp] push the type attribute
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and #$00FF
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pha
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lda [sp] push the private flag
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and #$FF00
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xba
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pha
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add4 sp,#2 sp += 2 {skip the attributes}
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ph2 #1 the symbol is global
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ph2 #1 the symbol is an expression
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ph4 sp push the address of the expression
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ph2 #0 push the data area flag
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ph2 #0 push the segment flag
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jsr Define define the symbol
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jsr SkipExpression skip the expression
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rts
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end
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****************************************************************
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*
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* Global - define a global label at the PC
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*
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* Inputs:
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* sp - pointer to the opcode
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*
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* Outputs:
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* sp - pointer to the next opcode
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*
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****************************************************************
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*
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Global private
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using Common
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inc4 sp skip the op code
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ph4 sp push the symbol name ptr
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lda [sp] skip the symbol name
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and #$00FF
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sec
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adc sp
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sta sp
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bcc lb1
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inc sp+2
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lb1 lda segVersion if the segment is version 0 ro 1 then
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cmp #2
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beq lb2
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lda [sp] push the length byte
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and #$00FF
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pha
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inc4 sp ++sp
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bra lb3 else
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lb2 lda [sp] push the length word
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pha
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add4 sp,#2 sp += 2
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lb3 anop endif
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lda [sp] push the type attribute
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and #$00FF
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pha
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lda [sp] push the private flag
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and #$FF00
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xba
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pha
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add4 sp,#2 sp += 2 {skip the attributes}
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ph2 #1 the symbol is global
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ph2 #0 the symbol is not an expression
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ph4 pc push the current pc
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ph2 #0 push the data area flag
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ph2 #0 push the segment flag
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jsr Define define the symbol
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rts
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end
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****************************************************************
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*
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* Invalid - invalid op code
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*
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* Notes:
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* An invalid opcode stops the link process with a
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* terminal error.
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*
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****************************************************************
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*
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Invalid private
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lda #8
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jmp TermError
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end
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|
****************************************************************
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|
*
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* LConst - long constant bytes
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*
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* Inputs:
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|
* sp - pointer to the opcode
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|
* pc - current program counter
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|
*
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* Outputs:
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* sp - pointer to the next opcode
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* pc - new program counter
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*
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****************************************************************
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*
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LConst private
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inc4 sp
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ldy #2
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lda [sp]
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sta r0
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lda [sp],Y
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sta r0+2
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add4 sp,r0
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add4 sp,#4
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add4 pc,r0
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rts
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end
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|
|
****************************************************************
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|
*
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* ListSeg - list the segment start info
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*
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* Inputs:
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* list - list info flag
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|
*
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****************************************************************
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*
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ListSeg private
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using Common
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lda list
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bne lb1
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lda progress
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beq lb1
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putc #'.'
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lb1 jsr CheckForPause
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rts
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end
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|
|
****************************************************************
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|
*
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* Local - define a local label at the PC
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|
*
|
|
* Inputs:
|
|
* sp - pointer to the opcode
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*
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|
* Outputs:
|
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* sp - pointer to the next opcode
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*
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|
****************************************************************
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|
*
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|
Local private
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|
using Common
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|
|
|
inc4 sp skip the op code
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ph4 sp push the symbol name ptr
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|
lda [sp] skip the symbol name
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and #$00FF
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sec
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adc sp
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sta sp
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bcc lb1
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inc sp+2
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lb1 lda segVersion if the segment is version 0 ro 1 then
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cmp #2
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beq lb2
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lda [sp] push the length byte
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and #$00FF
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pha
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inc4 sp ++sp
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bra lb3 else
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lb2 lda [sp] push the length word
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pha
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add4 sp,#2 sp += 2
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lb3 anop endif
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lda [sp] push the type attribute
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and #$00FF
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pha
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lda [sp] push the private flag
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and #$FF00
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xba
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pha
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add4 sp,#2 sp += 2 {skip the attributes}
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ph2 #0 the symbol is local
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ph2 #0 the symbol is not an expression
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|
ph4 pc push the current pc
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ph2 #0 push the data area flag
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|
ph2 #0 push the segment flag
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jsr Define define the symbol
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rts
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end
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|
|
|
****************************************************************
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|
*
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|
* Operation - handle an operation in an expression
|
|
*
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|
* Inputs:
|
|
* sp - pointer to the operation
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|
*
|
|
* Outputs:
|
|
* sp - pointer to the next expression term
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|
*
|
|
****************************************************************
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|
*
|
|
Operation private
|
|
|
|
inc4 sp
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rts
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|
end
|
|
|
|
****************************************************************
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|
*
|
|
* PrepareAlign - do pass 1 prep for an align on pass 2
|
|
*
|
|
* Inputs:
|
|
* r0 - alignmanr factor
|
|
* pc - program counter
|
|
*
|
|
* Outputs:
|
|
* pc - program counter
|
|
*
|
|
****************************************************************
|
|
*
|
|
PrepareAlign start
|
|
|
|
dec4 r0 align the PC
|
|
|
|
lb1 lda r0 quit if we are aligned
|
|
and pc
|
|
bne lb2
|
|
lda r2
|
|
and pc+2
|
|
beq lb5
|
|
lb2 lda r0 form the remaining bit mask
|
|
and pc
|
|
sta r4
|
|
lda r2
|
|
and pc+2
|
|
sta r6
|
|
lda #1 find the least significant bit
|
|
sta r8
|
|
stz r10
|
|
lb3 lda r8
|
|
and r4
|
|
bne lb4
|
|
lda r10
|
|
and r6
|
|
bne lb4
|
|
asl r8
|
|
rol r10
|
|
bra lb3
|
|
lb4 add4 pc,r8 add this to the pc
|
|
bra lb1 check the next bit
|
|
|
|
lb5 rts
|
|
end
|
|
|
|
****************************************************************
|
|
*
|
|
* RelExpr - evaluate a relative expression
|
|
*
|
|
* Inputs:
|
|
* sp - pointer to the opcode
|
|
* pc - current program counter
|
|
*
|
|
* Outputs:
|
|
* sp - pointer to the next opcode
|
|
* pc - new program counter
|
|
*
|
|
****************************************************************
|
|
*
|
|
RelExpr private
|
|
|
|
lda [sp] update the PC
|
|
xba
|
|
and #$00FF
|
|
clc
|
|
adc pc
|
|
sta pc
|
|
bcc lb1
|
|
inc pc+2
|
|
lb1 add4 sp,#6 skip the op code, length and offset
|
|
brl SkipExpression skip the expression
|
|
end
|
|
|
|
****************************************************************
|
|
*
|
|
* SkipExpression - skip an expression, noting label uses
|
|
*
|
|
* Inputs:
|
|
* sp - pointer to the first opcode in the expression
|
|
*
|
|
* Outputs:
|
|
* sp - pointer to the first opcode past the expression
|
|
*
|
|
****************************************************************
|
|
*
|
|
SkipExpression private
|
|
|
|
lb1 lda [sp]
|
|
and #$00FF
|
|
asl A
|
|
tax
|
|
jsr (addr,X)
|
|
bra lb1
|
|
|
|
addr dc a'EndExp' $00 End
|
|
dc 15a'Operation' $01..$0F some form of operation
|
|
dc 6a'Operation' $10..$15 some form of operation
|
|
dc 10a'Invalid' $16..$1F unused
|
|
dc 16a'Invalid' $20..$2F unused
|
|
dc 16a'Invalid' $30..$3F unused
|
|
dc 16a'Invalid' $40..$4F unused
|
|
dc 16a'Invalid' $50..$5F unused
|
|
dc 16a'Invalid' $60..$6F unused
|
|
dc 16a'Invalid' $70..$7F unused
|
|
dc a'Operation' $80 program counter
|
|
dc a'Value' $81 absolute value
|
|
dc a'WeakReference' $82 weak label reference
|
|
dc a'StrongReference' $83 strong label reference
|
|
dc a'StrongReference' $84 length attribute
|
|
dc a'StrongReference' $85 type attribute
|
|
dc a'WeakReference' $86 count attribute
|
|
dc a'Value' $87 disp from start of segment
|
|
dc 8a'Invalid' $88-8F unused
|
|
dc 16a'Invalid' $90..$9F unused
|
|
dc 16a'Invalid' $A0..$AF unused
|
|
dc 16a'Invalid' $B0..$BF unused
|
|
dc 16a'Invalid' $C0..$CF unused
|
|
dc 16a'Invalid' $D0..$DF unused
|
|
dc 16a'Invalid' $E0..$EF unused
|
|
dc 16a'Invalid' $F0..$FF unused
|
|
end
|
|
|
|
****************************************************************
|
|
*
|
|
* Strong - Note that we are using a data area
|
|
*
|
|
* Inputs:
|
|
* sp - pointer to the opcode
|
|
*
|
|
* Outputs:
|
|
* sp - pointer to the next opcode
|
|
*
|
|
****************************************************************
|
|
*
|
|
Strong private
|
|
|
|
inc4 sp skip the op code
|
|
jsr Reference make a reference to the name
|
|
lda [sp] skip the name in the obj segment
|
|
and #$00FF
|
|
sec
|
|
adc sp
|
|
sta sp
|
|
bcc lb1
|
|
inc sp+2
|
|
lb1 rts
|
|
end
|
|
|
|
****************************************************************
|
|
*
|
|
* StrongReference - handle a strong label reference in an expression
|
|
*
|
|
* Inputs:
|
|
* sp - pointer to the label name
|
|
*
|
|
* Outputs:
|
|
* sp - pointer to the next expression term
|
|
*
|
|
****************************************************************
|
|
*
|
|
StrongReference private
|
|
|
|
inc4 sp skip the op code
|
|
jsr Reference make a reference to the name
|
|
lda [sp] skip the name in the segment
|
|
and #$00FF
|
|
sec
|
|
adc sp
|
|
sta sp
|
|
bcc lb1
|
|
inc sp+2
|
|
lb1 rts
|
|
end
|
|
|
|
****************************************************************
|
|
*
|
|
* Value - handle a value in an expression
|
|
*
|
|
* Inputs:
|
|
* sp - pointer to the value
|
|
*
|
|
* Outputs:
|
|
* sp - pointer to the next expression term
|
|
*
|
|
****************************************************************
|
|
*
|
|
Value private
|
|
|
|
add4 sp,#5
|
|
rts
|
|
end
|
|
|
|
****************************************************************
|
|
*
|
|
* WeakReference - handle a weak label reference in an expression
|
|
*
|
|
* Inputs:
|
|
* sp - pointer to the label name
|
|
*
|
|
* Outputs:
|
|
* sp - pointer to the next expression term
|
|
*
|
|
****************************************************************
|
|
*
|
|
WeakReference private
|
|
|
|
lda [sp]
|
|
and #$FF00
|
|
xba
|
|
inc A
|
|
sec
|
|
adc sp
|
|
sta sp
|
|
bcc lb1
|
|
inc sp+2
|
|
lb1 rts
|
|
end
|