Start optimizing the emulator.

I also added a new input testing program called
input-3.s, which contains a mostly working editor.

2 files changed, 934 insertions, 0 deletions

diff --git a/test/input-2.s b/test/input-2.s
new file mode 100644
index 0000000..f5cb49e
--- /dev/null
+++ b/test/input-2.s
@@ -0,0 +1,412 @@
+; Testing input.
+;
+; Writen in Sux assembly by
+; mr b0nk 500 <b0nk@b0nk.xyz>
+
+; Instruction mnemonics,
+; and opcodes.
+.org $1000
+tok:
+	.byte "dab"
+msg:
+	.byte "oof, you divided a, and b on me.\n"
+
+; Input buffer.
+.org $2000
+buffer:
+
+.org $2800
+cmd_buf:
+
+; Initalize some variables.
+.org $0
+scr_row:
+	.byte $0
+scr_col:
+	.byte $0
+a:
+	.byte $0
+b:
+	.byte $0
+c:
+	.byte $0
+d:
+	.byte $0
+e:
+	.byte $0
+string:
+	.byte "Please, type something.\n"
+string2:
+	.byte "You typed, "
+end:
+	.byte $0
+
+; String Pointer
+ptr:
+	.qword buffer
+cptr:
+	.qword cmd_buf
+tptr:
+	.qword tok
+mptr:
+	.qword msg
+
+
+; Main program
+.org $8000
+reset:
+	cps
+	ldx.w #$FFFF
+	txs
+	ldy #0
+	lda #0
+clr_buf:
+	cpy.w #$7FF
+	beq start
+	sta (ptr), y
+	iny
+	jmp clr_buf
+
+start:
+	lda #0
+	sta $C000
+	tax		; Reset x.
+	tay		; Reset y.
+	jsl clr_cbuf
+	jmp print
+
+clr_cbuf:
+	cpy.w #$3FF
+	beq clr_cbuf_end
+	sta (cptr), y
+	iny
+	jmp clr_cbuf
+clr_cbuf_end:
+	ldy #0
+	rtl
+
+rset_a:
+	lda #1
+read:
+	lda $C000	; Get control register.
+	beq rset_a	; Loop until we get a character.
+	jmp getchar	; We got a key.
+sleep:
+	lda end
+	bne spin	; Are we done with getting input?
+
+print:
+	lda string, x	; Get character at offset x.
+	beq rset_a	; Did we find a null terminator?
+	sta $C001	; Print character.
+	inx		; Increment offset.
+	cmp #$A
+	beq inc_row
+	inc scr_col
+	jmp print
+inc_row:
+	lda #0
+	sta scr_col
+	lda #$42
+	sta c
+	jsl isdown
+	jmp print	; Keep printing more characters.
+
+getchar:
+	lda $C002	; Get typed character.
+	cmp #$1B
+	beq esc
+	cmp #$A
+	beq nl		; Did the user type a newline?
+	cmp #8
+	beq bs		; Did the user type a backspace?
+	cmp #$7F
+	beq bs		; Did the user type a backspace?
+echo:
+	sta a
+	ldx scr_col
+	cpx #79
+	bne echo_print
+linewrap:
+	inc scr_row
+	ldx #0
+	stx scr_col
+	lda scr_row
+	jsl update_pos
+echo_print:
+	lda a
+	sta $C001	; Echo typed character.
+	inc scr_col	; Increment the cursor's x coordinate.
+	sta (ptr), y	; Store typed character into the input buffer.
+	iny
+	jmp rset_a	; Start getting user input.
+
+esc:
+	lda $C000	; Skip the '['.
+	lda $C000	; Get the next character.
+	beq read	; We have an error, so discard it, and go back to getting user input.
+	lda $C002	; Get the escape code.
+	sta c		; Store the escape code, until we need it.
+	jsl isup	; Check if the user pressed up.
+	lda d
+	bne esc_end
+	jsl isdown	; Check if the user pressed down.
+	lda d
+	bne esc_end
+	lda #0
+	jsl isleft	; Check if the user pressed left.
+	lda d
+	bne esc_end
+	jsl isright	; Check if the user pressed right.
+esc_end:
+	lda #0
+	sta d
+	jmp rset_a	; Go back to getting user input.
+
+isup:
+	lda scr_row	; Is the cursor at the top of the screen?
+	beq isup_done	; Yes, so return.
+	lda c		; No, so load the escape code back into the accumulator.
+	cmp #$41	; Did the user press the up arrow key?
+	beq up		; Yes, so move the cursor up.
+isup_done:
+	rtl		; End of isup.
+
+isdown:
+	lda scr_row	; Start checking the y coordinate of the cursor.
+	cmp #23		; Is the cursor at the bottom of the screen?
+	beq isdown_done	; Yes, so return.
+	lda c		; No, so load the escape code back into the accumulator.
+	cmp #$42	; Did the user press the down arrow key?
+	beq down	; Yes, so move the cursor down.
+isdown_done:
+	rtl		; End of isdown.
+
+isright:
+	lda scr_col	; Start checking the x coordinate of the cursor.
+	cmp #79		; Is the cursor at the far right of the screen?
+	beq isright_end	; Yes, so return.
+	lda c		; No, so load the escape code back into the accumulator.
+	cmp #$43	; Did the user press the right arrow key?
+	beq right	; Yes, so move the cursor right.
+isright_end:
+	rtl		; End of isright.
+
+isleft:
+	lda scr_col	; Is the cursor at the far left of the screen?
+	beq isleft_done	; Yes, so return.
+	lda c		; No, so load the escape code back into the accumulator.
+	cmp #$44	; Did the user press the left arrow key?
+	beq left	; Yes, so move the cursor left.
+isleft_done:
+	rtl		; End of isleft.
+
+up:
+	dec scr_row
+	jsl update_pos
+	lda #1
+	sta d
+	jmp isup_done
+down:
+	inc scr_row
+	jsl update_pos
+	lda #1
+	sta d
+	jmp isdown_done
+right:
+	inc scr_col
+	jsl update_pos
+	jmp isright_end
+left:
+	dec scr_col
+	jsl update_pos
+	lda #1
+	sta d
+	jmp isleft_done
+
+update_pos:
+	lda #$1B	; Print an escape character
+	sta $C001	; to the screen.
+	lda #$5B	; Print '['
+	sta $C001	; to the screen, and start the escape sequence.
+	jsl getrow	; Start printing the row number to the screen.
+	jsl getcol	; Start printing the column number to the screen.
+	lda #$48	; Print 'H'
+	sta $C001	; to the screen.
+	rtl		; End of update_pos.
+getrow:
+	lda scr_row	; Get the cursor's y coordinate.
+	div #10		; Divide A by 10.
+	adc #$30	; Convert it to ascii, and
+	sta $C001	; print to the screen.
+	tba		; Get the remainder.
+	adc #$30	; Convert it to ascii, and
+	sta $C001	; print to the screen.
+	rtl		; End of getrow.
+getcol:
+	lda #$3B	; Print ';'
+	sta $C001	; to the screen.
+	lda scr_col	; Get the cursor's x coordinate.
+	div #10		; Divide A by 10.
+	adc #$30	; Convert it to ascii, and
+	sta $C001	; print to the screen.
+	tba		; Get the remainder.
+	adc #$30	; Convert it to ascii, and
+	sta $C001	; print to the screen.
+	rtl		; End of getrow.
+
+nl:
+	lda #0
+	sta scr_col
+	sta (ptr), y	; Store said terminator into the input buffer.
+	lda #$42
+	sta c
+	jsl isdown
+	ldy.w #0	; Reset y, to print the result.
+	jsl dabbed
+	beq start
+	ldy #0
+	jmp result
+
+back:
+	sta $C001	; Print backspace.
+	lda #0		; Put a null terminator, in place of the backspace.
+	sta (ptr), y	; Place it into the input buffer.
+	dey		; Decrement buffer offset.
+	dec scr_col
+	jmp read	; Get next character.
+
+bs:
+	cpy #0		; Are we at the start of the buffer?
+	beq rset_a	; We are, so do not store the backspace into the buffer.
+	jmp back	; We are not, so add the backspace to the buffer.
+
+result:
+	ldx scr_col
+	cpx #79
+	bne result_print
+linewrap2:
+	inc scr_row
+	ldx #$0
+	stx scr_col
+	jsl update_pos
+result_print:
+	lda string2, y
+	beq rset_y	; Reset y, if we hit the null terminator.
+	sta $C001	; Print 'You have typed, '
+	inc scr_col	; Increment the cursor's x coordinate.
+	iny		; Increment offset.
+	jmp result	; Keep printing.
+
+rset_y:
+	ldy.w #0	; Reset y.
+	ldx.w #0	; Reset x.
+	lda.w #0	; Reset a.
+	jmp print_buf	; Print the input buffer.
+dabbed:
+	lda (ptr), y	; Get a character from the input buffer.
+	beq dab_nend	; Are we done with printing the buffer?
+	cmp (tptr), y
+	bcs dab_nend
+	beq chk_str
+	bcc dab_nend
+chk_str:
+	iny
+	cpy #3
+	bne dabbed
+	ldy #0
+pnt_msg:
+	ldx scr_col
+	cpx #79
+	bne msg_pnt
+linewrap3:
+	inc scr_row
+	ldx #0
+	stx scr_col
+	jsl update_pos
+msg_pnt:
+	lda (mptr), y	; Get a character from the input buffer.
+	beq dab_eqnd	; Are we done with printing the buffer?
+	sta $C001	; Print said character.
+	inc scr_col	; Increment the cursor's x coordinate.
+	iny
+	jmp pnt_msg	; Keep printing the buffer.
+dab_nend:
+	lda #1
+	jmp dab_end
+dab_eqnd:
+	lda #0
+	jmp dab_end
+dab_end:
+	rtl
+
+
+
+print_buf:
+	ldx scr_col
+	cpx #79
+	bne buf_print
+linewrap4:
+	inc scr_row
+	ldx #0
+	stx scr_col
+	jsl update_pos
+buf_print:
+	lda (ptr), y	; Get a character from the input buffer.
+	beq cmd_clr	; Are we done with printing the buffer?
+	sta $C001	; Print said character.
+	inc scr_col	; Increment the cursor's x coordinate.
+	iny
+	jmp print_buf	; Keep printing the buffer.
+
+cmd_clr:
+	lda #0
+	sta scr_col
+	lda #$42
+	sta c
+	jsl isdown
+	jmp start
+
+scr_to_buf:
+	tax
+	mul #80
+	adc scr_col
+	tay
+	txa
+	rtl
+
+spin:
+	nop
+	nop
+	nop
+	jmp spin
+
+.org $1000
+v
+.org $1100
+v
+.org $1200
+v
+.org $8000
+v
+.org $8100
+v
+.org $8200
+v
+.org $8300
+v
+.org $FFC0
+.qword reset
+
+.org $FF50
+.qword spin
+.qword spin
+.qword spin
+.qword spin
+.qword spin
+.qword spin
+.qword spin
+.org $FF50
+v
+done
+
diff --git a/test/input-3.s b/test/input-3.s
new file mode 100644
index 0000000..a05cb9d
--- /dev/null
+++ b/test/input-3.s
@@ -0,0 +1,522 @@
+; Testing input.
+;
+; Writen in Sux assembly by
+; mr b0nk 500 <b0nk@b0nk.xyz>
+
+; Instruction mnemonics,
+; and opcodes.
+.org $1000
+tok:
+	.byte "dab"
+msg:
+	.byte "oof, you divided a, and b on me.\n"
+
+; Input buffer.
+.org $2000
+buffer:
+
+.org $4000
+cmd_buf:
+
+.org $200
+bitmask:
+	.byte $0
+bitabl:
+	.qword $0
+	.word $0
+bits:
+	.byte $0
+
+; Initalize some variables.
+.org $0
+scr_row:
+	.byte $0
+scr_col:
+	.byte $0
+scr_lnst:
+	.word $0
+scr_lncnt:
+	.word $0
+scr_rowst:
+	.byte $0
+a:
+	.byte $0
+b:
+	.byte $0
+c:
+	.byte $0
+d:
+	.byte $0
+e:
+	.byte $0
+string:
+	.byte "Please, type something.\n"
+string2:
+	.byte "You typed, "
+end:
+	.byte $0
+
+; Pointers
+ptr:
+	.qword buffer
+cptr:
+	.qword cmd_buf
+tptr:
+	.qword tok
+mptr:
+	.qword msg
+bmptr:
+	.qword bitmask
+btptr:
+	.qword bitabl
+
+; Main program
+.org $8000
+reset:
+	cps
+	ldx.w #$FFFF
+	txs
+	ldy #0
+	lda #0
+	jsl clr_buf
+	jmp start
+clr_buf:
+	lda #0
+	cpy.w #$1FFF
+	beq clr_buf_end
+	sta (ptr), y
+	iny
+	jmp clr_buf
+clr_buf_end:
+	ldy.w #0
+	rtl
+
+start:
+	lda #0
+	tax
+	sta $C000
+	phy #2
+	ldy.w #0
+	jsl clr_cbuf
+	ply #2
+	lda #1
+	sta $C000
+	jmp print
+
+clr_cbuf:
+	cpy.w #$3FF
+	beq clr_cbuf_end
+	sta (cptr), y
+	iny
+	jmp clr_cbuf
+clr_cbuf_end:
+	rtl
+
+pull_y:
+	ply #2
+rset_a:
+	lda #0
+	sta $C000
+	inc
+read:
+	lda $C000	; Get control register.
+	beq rset_a	; Loop until we get a character.
+	jsl getchar	; We got a key.
+	beq parse	; We got a newline, so start parsing the line.
+	jmp rset_a	; We didn't get a newline, so keep getting more characters.
+sleep:
+	lda end
+	bne spin	; Are we done with getting input?
+
+print:
+	phy #2
+	txy
+	lda string, y	; Get character at offset x.
+	beq pull_y	; Did we find a null terminator?
+	ply #2
+	inx
+	jsl print_char
+	jmp print
+
+getbit:
+	phy #2
+	ldx scr_row
+getbt1:
+	jsl bitpos
+	txy
+	ldb (btptr), y
+	ply #2
+	aba
+	cmp #1
+	jmp bitout
+
+bitpos:
+	stx bitmask
+	txa
+	and #7
+	tax
+	lda bits, x
+	pha #1
+	lda bitmask
+	lsr #3
+	tax
+	pla #1
+	rtl
+
+bitout:
+	ldx bitmask
+	rtl
+
+getchar:
+	lda $C002	; Get typed character.
+	pha #1
+	phy #2
+	cmp #10
+	beq cmd_cpy
+getchar_pnt:
+	ply #2
+	pla #1
+	jsl print_char
+	lda a
+	cmp #10
+	beq getchar_line
+	jmp getchar_char
+cmd_cpy:
+	lda scr_row
+	mul #80
+	tay
+	ldx.w #$0
+cmd_cpy_strt:
+	lda (ptr), y
+	beq getchar_pnt
+	phy #2
+	txy
+	sta (cptr), y
+	inx
+	ply #2
+	iny
+	jmp cmd_cpy_strt
+getchar_line:
+	lda #$0
+	sta scr_lncnt
+	jmp getchar_end
+getchar_char:
+	lda #$1
+getchar_end:
+	rtl
+
+parse:
+	lda #0
+	tax
+	jsl dabbed
+	beq start
+	lda #0
+	tax
+	jmp result
+
+print_char:
+	sta a
+	cmp #$1B
+	beq esc
+	cmp #$A
+	beq nl		; Did the user type a newline?
+	cmp #$C
+	beq clr_scr
+	cmp #8
+	beq bs		; Did the user type a backspace?
+	cmp #$7F
+	beq bs		; Did the user type a backspace?
+	sta a
+	ldb scr_col
+	cpb #79
+	beq linewrap
+	jmp printc
+linewrap:
+	ldb #0
+	stb scr_col
+	lda #$42
+	sta c
+	jsl isdown
+	ldb scr_row
+	cpb #23
+	beq printc_end
+printc:
+	lda a
+	inc scr_col	; Increment the cursor's x coordinate.
+	inc scr_lncnt
+	sta (ptr), y	; Store typed character into the input buffer.
+	iny
+	sta $C001	; Echo typed character.
+printc_end:
+	rtl
+
+nl:
+	lda #0
+	sta (ptr), y	; Store said terminator into the input buffer.
+	sta scr_col
+	lda scr_row
+	cmp #23
+	bne nl_inc
+	lda #1
+	sta a
+	jmp printc_end
+nl_inc:
+	lda #$42
+	sta c
+	jsl isdown
+	sty.w scr_lnst
+	lda #10
+	sta a
+	jmp printc_end
+
+clr_scr:
+	lda #0
+	sta.w scr_lnst
+	sta scr_rowst
+	tay
+	jsl clr_buf
+	sta scr_col
+	sta scr_row
+	jsl update_pos
+	lda #$C
+	sta $C001
+	jmp printc_end
+
+back:
+	lda #$7F
+	sta $C001
+	dey		; Decrement buffer offset.
+	lda #0		; Put a null terminator, in place of the backspace.
+	sta (ptr), y	; Place it into the input buffer.
+	lda #$44
+	dec scr_col
+	dec scr_lncnt
+	jsl update_pos
+	jmp printc_end	; Get next character.
+
+bs:
+	lda scr_col	; Are we at the start of the buffer?
+	beq printc_end
+	jmp back	; We are not, so add the backspace to the buffer.
+
+esc:
+	lda $C000	; Skip the '['.
+	lda $C000	; Get the next character.
+	beq printc_end	; We have an error, so discard it, and go back to getting user input.
+	lda $C002	; Get the escape code.
+	sta c		; Store the escape code, until we need it.
+	lda #0
+	sta d
+	jsl isup	; Check if the user pressed up.
+	lda e
+	bne esc_lnst
+	lda d
+	bne esc_end
+	jsl isdown	; Check if the user pressed down.
+	lda e
+	bne esc_lnst
+	lda d
+	bne esc_end
+	lda #0
+	jsl isleft	; Check if the user pressed left.
+	lda d
+	bne esc_end
+	jsl isright	; Check if the user pressed right.
+	jmp esc_end
+esc_lnst:
+	lda scr_row
+	sta scr_rowst
+	mul #80
+	sta.w scr_lnst
+esc_end:
+	lda #0
+	sta d
+	jmp printc_end	; Go back to getting user input.
+
+isup:
+	lda scr_row	; Is the cursor at the top of the screen?
+	beq isup_done	; Yes, so return.
+	lda c		; No, so load the escape code back into the accumulator.
+	cmp #$41	; Did the user press the up arrow key?
+	beq up		; Yes, so move the cursor up.
+isup_done:
+	rtl		; End of isup.
+
+isdown:
+	lda scr_row	; Start checking the y coordinate of the cursor.
+	cmp #23		; Is the cursor at the bottom of the screen?
+	beq isdown_done	; Yes, so return.
+	lda c		; No, so load the escape code back into the accumulator.
+	cmp #$42	; Did the user press the down arrow key?
+	beq down	; Yes, so move the cursor down.
+	jmp isdown_done
+isdown_scrl:
+	lda #$1B	; Print an escape character
+	sta $C001	; to the screen.
+	lda #$5B	; Print '['
+	sta $C001	; to the screen, and start the escape sequence.
+	lda #$54	; Print 'T'
+	sta $C001	; to the screen, and end the escape sequence.
+isdown_done:
+	rtl		; End of isdown.
+
+isright:
+	lda scr_col	; Start checking the x coordinate of the cursor.
+	cmp #79		; Is the cursor at the far right of the screen?
+	beq isright_end	; Yes, so return.
+	lda c		; No, so load the escape code back into the accumulator.
+	cmp #$43	; Did the user press the right arrow key?
+	beq right	; Yes, so move the cursor right.
+isright_end:
+	rtl		; End of isright.
+
+isleft:
+	lda scr_col	; Is the cursor at the far left of the screen?
+	beq isleft_done	; Yes, so return.
+	lda c		; No, so load the escape code back into the accumulator.
+	cmp #$44	; Did the user press the left arrow key?
+	beq left	; Yes, so move the cursor left.
+isleft_done:
+	rtl		; End of isleft.
+
+up:
+	dec scr_row
+	jsl update_pos
+	lda #1
+	sta d
+	jmp isup_done
+down:
+	inc scr_row
+	jsl update_pos
+	lda #1
+	sta d
+	jmp isdown_done
+right:
+	inc scr_col
+	jsl update_pos
+	jmp isright_end
+left:
+	dec scr_col
+	jsl update_pos
+	lda #1
+	sta d
+	jmp isleft_done
+
+update_pos:
+	lda scr_row
+	mul #80
+	adc scr_col
+	tay
+	lda #$1B	; Print an escape character
+	sta $C001	; to the screen.
+	lda #$5B	; Print '['
+	sta $C001	; to the screen, and start the escape sequence.
+	jsl getrow	; Start printing the row number to the screen.
+	jsl getcol	; Start printing the column number to the screen.
+	lda #$48	; Print 'H'
+	sta $C001	; to the screen.
+	rtl		; End of update_pos.
+
+getrow:
+	lda scr_row	; Get the cursor's y coordinate.
+	div #10		; Divide A by 10.
+	adc #$30	; Convert it to ascii, and
+	sta $C001	; print to the screen.
+	tba		; Get the remainder.
+	adc #$30	; Convert it to ascii, and
+	sta $C001	; print to the screen.
+	rtl		; End of getrow.
+
+getcol:
+	lda #$3B	; Print ';'
+	sta $C001	; to the screen.
+	lda scr_col	; Get the cursor's x coordinate.
+	div #10		; Divide A by 10.
+	adc #$30	; Convert it to ascii, and
+	sta $C001	; print to the screen.
+	tba		; Get the remainder.
+	adc #$30	; Convert it to ascii, and
+	sta $C001	; print to the screen.
+	rtl		; End of getrow.
+
+result:
+	phy #2
+	txy
+	lda string2, y
+	beq rset_y	; Reset y, if we hit the null terminator.
+	ply #2
+	jsl print_char	; Print 'You have typed, '
+	inx
+	jmp result	; Keep printing.
+
+rset_y:
+	ply #2
+	lda #0		; Reset a.
+	tax		; Reset y.
+	jmp print_buf	; Print the input buffer.
+
+dabbed:
+	phy #2
+	txy
+	lda (cptr), y	; Get a character from the input buffer.
+	beq dab_pend	; Are we done with printing the buffer?
+	cmp (tptr), y
+	bcs dab_pend
+	beq chk_str
+	bcc dab_pend
+chk_str:
+	ply #2
+	inx
+	cpx #3
+	bne dabbed
+	ldx #0
+pnt_msg:
+	phy #2
+	txy
+	lda (mptr), y	; Get a character from the input buffer.
+	beq dab_peqnd	; Are we done with printing the buffer?
+	ply #2
+	jsl print_char
+	inx
+	jmp pnt_msg	; Keep printing the buffer.
+dab_pend:
+	ply #2
+	lda #1
+	jmp dab_end
+dab_peqnd:
+	ply #2
+	lda #0
+	jmp dab_end
+dab_end:
+	rtl
+
+print_buf:
+	phy #2
+	txy
+	lda (cptr), y	; Get a character from the input buffer.
+	beq cmd_clr	; Are we done with printing the buffer?
+	ply #2
+	jsl print_char
+	inx
+	jmp print_buf	; Keep printing the buffer.
+
+cmd_clr:
+	ply #2
+	lda #10
+	jsl print_char
+	jmp start
+
+.org $FFC0
+.qword reset
+
+.org $FF50
+.qword spin
+.qword spin
+.qword spin
+.qword spin
+.qword spin
+.qword spin
+.qword spin
+.org $FF50
+done
+