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Update some comments
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@ -365,7 +365,7 @@ _ApplyBG0XPos
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ldx :draw_count_x2
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ldx :draw_count_x2
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lda :opcode
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lda :opcode
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ldy :base_address
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ldy :base_address ; Y-register is preserved, this can be removed
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jsr SetCodeEntryOpcode
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jsr SetCodeEntryOpcode
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; If this is an odd entry, also set the odd_entry low byte and save the operand high byte
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; If this is an odd entry, also set the odd_entry low byte and save the operand high byte
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@ -374,11 +374,11 @@ _ApplyBG0XPos
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beq :not_odd
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beq :not_odd
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ldx :draw_count_x2
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ldx :draw_count_x2
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ldy :base_address
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ldy :base_address ; Y-register is preserved, this can be removed
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jsr SetOddCodeEntry
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jsr SetOddCodeEntry
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ldx :draw_count_x2
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ldx :draw_count_x2
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ldy :base_address
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ldy :base_address ; Y-register is preserved, this can be removed
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pei :exit_address
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pei :exit_address
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jmp :SaveHighOperand ; Only used once, so "inline" it
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jmp :SaveHighOperand ; Only used once, so "inline" it
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:save_high_op_rtn
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:save_high_op_rtn
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@ -584,15 +584,18 @@ full_return jml blt_return ; Full exit
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; The even/odd branch of this line's exception handler will return here. This is mostly
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; The even/odd branch of this line's exception handler will return here. This is mostly
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; a space-saving measure to allow for more code in the exeption handers themselved, but
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; a space-saving measure to allow for more code in the exeption handers themselves, but
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; also simplified the relocation process since we only have to update a single address
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; also simplifies the relocation process since we only have to update a single address
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; in each exception handler, rather than two.
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; in each exception handler, rather than two.
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;
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;
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; Oce working, this code should be able to be interleaved with the r_jmp_rtn code
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; Once working, this code should be able to be interleaved with the r_jmp_rtn code
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; above to eliminate a couple of branches
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; above to eliminate a couple of branches
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jmp_rtn
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jmp_rtn
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bvs r_jmp_rtn
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bvs r_jmp_rtn
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jmp_rtn_1 jmp l_jmp_rtn-base ; Could inline the code and save 3 cycles / line
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jmp_rtn_1 jmp l_jmp_rtn-base ; Could inline the code and save 3 cycles / line
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; If we switch even/odd exit points, could fall through
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; to the even_exit JMP at the head of the PEA field to
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; save 6 cycles.
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; Re-enable interrupts and continue -- the even_exit JMP from the previous line will jump here every
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; Re-enable interrupts and continue -- the even_exit JMP from the previous line will jump here every
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; 8 or 16 lines in order to give the system time to handle interrupts.
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; 8 or 16 lines in order to give the system time to handle interrupts.
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@ -653,7 +656,7 @@ long_4 stal *+4-base
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l_jmp_rtn xba
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l_jmp_rtn xba
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sep #$20
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sep #$20
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pha
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pha
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rep #$61 ; Clear everything C, V and M
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rep #$61 ; Clear everything C, V and M
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bra even_exit
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bra even_exit
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l_is_jmp sec ; Set the C flag (V is always cleared at this point) which tells a snippet to push only the high byte
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l_is_jmp sec ; Set the C flag (V is always cleared at this point) which tells a snippet to push only the high byte
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