From df81112b8369eeca5788a6f28c6b6b85ca911a95 Mon Sep 17 00:00:00 2001 From: mrb0nk500 Date: Mon, 1 Jun 2020 15:15:17 -0400 Subject: Did some more refactoring to the assembler. - Refactored the symbol, and fixup table to now use a linked list - Added support for local symbols to the assembler. - Rewrote SuBEditor, and SuBAsm to use local symbols. --- programs/subeditor.s | 431 ++++++++++++++++++++++++++------------------------- 1 file changed, 217 insertions(+), 214 deletions(-) (limited to 'programs/subeditor.s') diff --git a/programs/subeditor.s b/programs/subeditor.s index 0a42c32..26c6f7d 100644 --- a/programs/subeditor.s +++ b/programs/subeditor.s @@ -151,9 +151,9 @@ clr_arr: jsr set_ptr ; deb ; Set B back to zero. tba ; -clr_arr_st: +@loop: cpy.w scr_ptr ; Did we clear all of the array? - bcs clr_arr_end ; Yes, so we're done. + bcs @end ; Yes, so we're done. sta.q (ptr), y ; No, so clear eight bytes. sta.q (ptr2), y ; Clear eight more bytes. tya ; Copy the array index. @@ -166,8 +166,8 @@ clr_arr_st: adc #$10 ; tay ; tba ; - jmp clr_arr_st ; Keep looping. -clr_arr_end: + jmp @loop ; Keep looping. +@end: ldy.w zero ; Set the index back to zero. plb #1 ; Get whatever was in the B register, back. rts ; End of clr_arr. @@ -219,27 +219,27 @@ read: print_str: ldx #0 ; Reset X. sta.q end ; Save the parameter. -print_str2: +@reset: lda.q end ; Get the parameter. ldb #0 ; Clear the B register. jsr set_ptr ; Set the first pointer to the parameter. tba ; Clear the Accumulator. -pntstr_lp: +@loop: ldb #1 ; Enable replace mode. stb b ; lda.q ptr ; Get the first pointer. cmp.q end ; Did the pointer change? - bne print_str2 ; Yes, so set it back. + bne @reset ; Yes, so set it back. and #0 ; No, reset the accumulator. phy #2 ; Save the cursor index. txy ; Copy the string index into Y. lda (ptr), y ; Are we at the end of the string? ply #2 ; Get the cursor index back. - beq pntstr_end ; Yes, so we're done. + beq @end ; Yes, so we're done. inx ; No, so increment the string index. jsr print_char ; Print the character. - jmp pntstr_lp ; Keep looping. -pntstr_end: + jmp @loop ; Keep looping. +@end: ldb #0 ; Enable insert mode. stb b ; rts ; End of print_str. @@ -334,37 +334,37 @@ getchar: pha #1 ; Save the character. phy #2 ; Save the cursor index. cmp #'\n' ; Was the character that was typed, a newline? - bne getchar_pnt ; No, so just print the character. + bne @print ; No, so just print the character. jsr cmd_cpy ; Yes, so start copying the line to the command buffer. -getchar_pnt: +@print: ply #2 ; Get back the cursor index. pla #1 ; Get back the character. ldb e ; Is the temporary row position non zero? - bne reset_row ; Yes, so reset the row positon. -getchar_pt1: + bne @row ; Yes, so reset the row positon. +@print1: jsr print_char ; No, so print the character. lda a ; Get the return value. cmp #'\n' ; Is the return value, a newline? - beq getchar_ln ; Yes, so return 0. - jmp getchar_chr ; No, so return 1. -reset_row: + beq @true ; Yes, so return true. + jmp @false ; No, so return false. +@row: ldb e ; Get the temporary row position. cpb #maxrow ; Is temporary row position, at, or above the bottom of the screen? - beq reset_row2 ; Yes, so leave it as is. - bcs reset_row1 ; No, so set it to the bottom of the screen. - jmp reset_row2 ; Yes, so leave it as is. -reset_row1: + beq @row2 ; Yes, so leave it as is. + bcs @row1 ; No, so set it to the bottom of the screen. + jmp @row2 ; Yes, so leave it as is. +@row1: ldb #maxrow ; Set the row position to the bottom of the screen. -reset_row2: +@row2: stb scr_row ; Set the row position. - jmp getchar_pt1 ; Print the character. -getchar_ln: - lda #0 ; Return zero. - jmp getchar_end ; We are done. -getchar_chr: - lda #1 ; Return one. -getchar_end: - rts ; End of get char. + jmp @print1 ; Print the character. +@true: + lda #0 ; Return true. + jmp @end ; We are done. +@false: + lda #1 ; Return false. +@end: + rts ; End of getchar. cmd_cpy: @@ -372,12 +372,12 @@ cmd_cpy: sta scr_trow ; Save it for later. jsr findend ; Find the end of the line. ldb scr_str ; Has the screen been scrolled? - beq cmd_cpy3 ; No, so don't subtract the screen's starting point from the line number. -cmd_cpy2: + beq @start ; No, so don't subtract the screen's starting point from the line number. +@offset: sec ; Yes, so make sure that we don't subtract by the starting point, plus one. sbc scr_str ; Offset the row position, back by the screen's starting point. clc ; Clear the carry flag, so that nothing odd occurs. -cmd_cpy3: +@start: sta scr_row ; Set the row position to the end of the line. sta e ; Save it into the temporary row posiition. jsr findst ; Find the start of the line. @@ -395,53 +395,53 @@ cmd_cpy3: jsr set_ptr ; deb ; Set B back to zero. tba ; Set the accumulator to zero. -cmd_cpy_lp: +@loop: ldb #0 ; Reset the B register. lda.q (ptr), y ; Get eight bytes from the current line. -cmd_cpy_lp1: +@loop1: phy #2 ; Save the screen index. txy ; Get the command buffer index. sta (ptr2), y ; Copy one byte from the screen buffer, to the command buffer. inx ; Increment the command buffer index. ply #2 ; Get back the screen index. cpx.w #$3FF ; Are we at the end of the command buffer? - bcs cmd_cpy_nd0 ; Yes, so we're done. + bcs @end ; Yes, so we're done. iny ; No, so increment the screen index. inb ; Increment the byte count. lsr #8 ; Shift in the next byte. stb g ; Save the byte count. tab ; Save the string buffer. and #$FF ; Is this byte of the buffer, a null terminator? - beq cmd_cpy_nd ; Yes, so we're done. + beq @end1 ; Yes, so we're done. tba ; No so get back the string buffer. ldb g ; Get back the byte count. cpb #7 ; Did we shift in eight bytes? - beq cmd_cpy_lp ; Yes, so get eight more bytes. - jmp cmd_cpy_lp1 ; No, so keep shifting in more bytes. -cmd_cpy_nd0: + beq @loop ; Yes, so get eight more bytes. + jmp @loop1 ; No, so keep shifting in more bytes. +@end: ldb #0 ; Reset B. phy #2 ; Save the screen index. txy ; Get the command buffer index. stb (ptr2), y ; Terminate the command buffer. ply #2 ; Get back the screen index. -cmd_cpy_nd: +@end1: tab ; The B register is zero, so clear the Accumulator. rts ; End of cmd_cpy. findst: lda #0 ; Reset A. -findst_lp: +@loop: pha #1 ; Save the current line number. jsr getbit ; Is this the start of the line? pla #1 ; Get the current line number back. - bcc findst_done ; Yes, so we're done. + bcc @end ; Yes, so we're done. inc ; No, so check the next physical line. dec scr_row ; Are we at the top of the screen? - bpo findst_lp ; No, so keep looping. + bpo @loop ; No, so keep looping. dec ; Yes, so move back one line. inc scr_row ; Put the row postiion back to zero. -findst_done: +@end: cmp #0 ; Update all the flags. rts ; End of findst. @@ -454,12 +454,12 @@ fndend: tba ; Set the Accumulator to zero. plb #1 ; Restore the contents of the B register. phy #2 ; -fndend_lp: +@loop: lda (ptr), y ; Are we at the end of the string? - beq fndend_done ; Yes, so we're done. + beq @end ; Yes, so we're done. iny ; No, so increment the cursor index. - jmp fndend_lp ; Keep looping. -fndend_done: + jmp @loop ; Keep looping. +@end: sty.w scr_ptr3 ; ply #2 ; rts ; End of fndend. @@ -502,22 +502,22 @@ printc: lda #0 ; No, so start trying to print a character. sta d ; lda (ptr3), y ; Are we at the end of the string? - beq printc_save ; Yes, so just print the character. + beq @save ; Yes, so just print the character. lda b ; No, but was the flag set? - bne printc_save ; Yes, so don't shift the line. + bne @save ; Yes, so don't shift the line. sty.w scr_ptr ; No, so save the cursor index for later. jsr fndend ; Find the end of the line. - jmp prntc_movln ; Start shifting the line right. -prntc_updt: + jmp @shift ; Start shifting the line right. +@update: lda scr_col ; Save the current column position for later. sta scr_tcol ; -prntc_updt2: +@update1: jsr findend ; Find the end of the line. sta e ; Use it for redrawing the line. sta scr_row ; Set the row position to to the end of the line. jsr findst ; Find the start of the line. lda scr_row ; Get the start of the line. -prntc_updt3: +@update2: sta f ; Set the starting line, to the start of the line. jsr rdrw_ln ; Redraw the line. lda scr_trow ; Get the real row position back. @@ -526,8 +526,8 @@ prntc_updt3: sta scr_col ; jsr update_pos ; Update the cursor's position. dec d ; - jmp printc_sav1 ; -prntc_movln: + jmp @save1 ; +@shift: ldy.w scr_ptr3 ; inc scr_ptr3 ; tyx ; @@ -541,51 +541,50 @@ prntc_movln: sta (ptr3), y ; store typed character into the input buffer. lda scr_row ; sta scr_trow ; - jmp prntc_updt ; -printc_save: + jmp @update ; +@save: ldb d ; - bne prntc_updt ; -printc_sav1: + bne @update ; +@save1: lda a ; sta (ptr3), y ; store typed character into the input buffer. -printc_inc: +@incr: inc scr_col ; Increment the cursor's x coordinate. iny ; -printc_2: +@wrapped: ldb #1 ; stb f ; ldb scr_col ; cpb #maxcol+1 ; - bcs printc_4 ; -printc_3: + bcs @scrolled ; +@print: sta scr ; Echo typed character. ldb f ; - beq printc_wrap ; + beq @wrap ; jmp printc_end ; -printc_4: +@scrolled: ldb scr_row ; cpb #maxrow ; - bcs printc_scrl ; -printc_5: + bcs @scroll ; +@wrapped2: ldb #0 ; stb f ; - jmp printc_3 ; -printc_scrl: + jmp @print ; +@scroll: sta scr ; Echo typed character. clc ; lda #1 ; sta wrapped ; jsr scrl_down ; - jmp printc_wrap ; -printc_wrap: +@wrap: ldb #0 stb scr_col ; ldb scr_row ; cpb #maxrow ; - bcs printc_wrp2 ; -printc_wrap1: + bcs @wrap2 ; +@wrap1: inc scr_row ; -printc_wrp2: +@wrap2: phx #2 ; clc ; lda scr_row ; @@ -600,19 +599,19 @@ printc_end: nl: lda #0 ; Reset A. ldb (ptr3), y ; Is this character not a null terminator? - bne nl1 ; Yes, so don't overwrite it. + bne @scroll ; Yes, so don't overwrite it. sta (ptr3), y ; No, so overwrite it. -nl1: +@scroll: sta scr_col ; Move the cursor to the start of the next line. lda scr_row ; Get the row position. cmp #maxrow ; Are we at the bottom of the screen? - bcc nl_inc ; No, so move down one line. + bcc @incr ; No, so move down one line. jsr scrl_down ; Yes, so scroll down one line. - jmp nl_end ; We are done. -nl_inc: + jmp @end ; We are done. +@incr: inc scr_row ; Move the cursor down by one line. jsr update_pos ; Update the cursor's position. -nl_end: +@end: lda #'\n' ; Print the newline. sta a ; jmp printc_end ; @@ -667,13 +666,13 @@ back: sta scr_trow ; jsr findend ; Find the end of the line. sta scr_row ; Set our row position to the end of the line. -back0: +@find_st: jsr findst ; Does this line take up more than one real line? - beq back1 ; No, so skip updating any other lines. - bcs back_updt ; Yes, so update the other lines. + beq @shift ; No, so skip updating any other lines. + bcs @update ; Yes, so update the other lines. lda scr_trow ; Get the real row position back. sta scr_row ; -back1: +@shift: dey ; Decrement the buffer's offset. lda #0 ; Place a null terminator sta (ptr3), y ; into the buffer. @@ -685,8 +684,8 @@ back1: lda #$7F ; Print a backspace to the screen. sta scr ; lda e ; Are we updating more than one line? - beq back3 ; No, so skip to the next step. -back2: + beq @load ; No, so skip to the next step. +@find_end: jsr findend ; Yes, so find the end of the line. sta e ; Set the end parameter to it. lda scr_col ; Save the current column position for now. @@ -694,44 +693,44 @@ back2: jsr rdrw_ln ; Start redrawing the line. lda scr_tcol ; Get the real column position back. sta scr_col ; -back3: - lda scr_trow ; Get the real row position bac. +@load: + lda scr_trow ; Get the real row position back. sta scr_row ; dec scr_col ; Move the cursor back by one column, jsr update_pos ; and update it's position. jmp printc_end ; We are done. -back_updt: +@update: lda scr_row ; Set the line to start redrawing, to the start of the line. sta f ; inc e ; Set the redraw flag to true. - jmp back1 ; Start shifting the line back. + jmp @shift ; Start shifting the line back. bs: lda scr_col ; Are we at the far left of the screen? - beq back_wrap ; Yes, so check for a wrapped line. + beq @wrap ; Yes, so check for a wrapped line. jmp back ; No, so add the backspace to the buffer. -back_wrap: +@wrap: jsr getbit ; Is this line, a wrapped line? - bcs back_wrap1 ; Yes, so check if the cursor is at the top. + bcs @wrap1 ; Yes, so check if the cursor is at the top. jmp printc_end ; No, so we're done. -back_wrap1: +@wrap1: lda scr_row ; Are we at the top of the screen? - beq back_wrap2 ; Yes, so check if the screen is at the top of the buffer. - jmp backwrp ; No, so start clearing the wrap bit. -back_wrap2: + beq @wrap2 ; Yes, so check if the screen is at the top of the buffer. + jmp @wrap3 ; No, so start clearing the wrap bit. +@wrap2: lda scr_str ; Are we at the top of the buffer? - bne back_scrl ; Yes, so scroll up. + bne @scroll ; Yes, so scroll up. jmp printc_end ; No, so we're done. -back_scrl: +@scroll: clc ; Clear the carry flag, so that we don't get odd behaviour. jsr scrl_up ; Scroll up. inc scr_row ; Move down by one row. -backwrp: +@wrap3: clc ; Clear the carry flag. lda scr_row ; Add the cursor's row position, adc scr_str ; and the screen's starting row. tax ; Transfer that into X. -backwrp2: +@wrap4: dec scr_row ; Move up by one row. ldb #maxcol+1 ; Move the cursor to the absolute right of the screen. stb scr_col ; @@ -740,20 +739,20 @@ backwrp2: shftln: ldb d ; Is the flag not set? - beq shftln_lp1 ; Yes, so shift, and decrement. + beq @dec_loop ; Yes, so shift, and decrement. ldb #0 ; Clear the B register. - jmp shftln_lp0 ; No, so shift, and increment. -shftln_neg: + jmp @inc_loop ; No, so shift, and increment. +@neg: ldy.w zero ; Set the source poition to 0. stb (ptr3), y ; Clear the character that is in the source. - jmp shftln_end ; We are done. -shftln_lp0: + jmp @end ; We are done. +@inc_loop: sty.w scr_ptr2 ; Save the source position for later. ldy.w scr_ptr ; Get the previous cursor index. cpy.w scr_ptr2 ; Is the source position, at, or below the cursor index? - beq shftln_lp01 ; Yes, so keep looping. - bcs shftln_end ; No, so we're done. -shftln_lp01: + beq @inc_loop1 ; Yes, so keep looping. + bcs @end ; No, so we're done. +@inc_loop1: ldy.w scr_ptr2 ; Get the source position. lda (ptr3), y ; Get the character from the source position. phy #2 ; Save the source position for later. @@ -761,14 +760,14 @@ shftln_lp01: sta (ptr3), y ; Place the character from the source position, to the destination position. ply #2 ; Set our position back to the source. stb (ptr3), y ; Clear the character that is in the source. - bng shftln_neg ; The source underflowed, so set it back to zero, + bng @neg ; The source underflowed, so set it back to zero, dey ; Decrement the source position. dex ; Decrement the destination position. - jmp shftln_lp0 ; Keep looping. -shftln_lp1: + jmp @inc_loop ; Keep looping. +@dec_loop: stx.w scr_ptr2 ; Save the destination position for later. lda (ptr3), y ; Is the character at the source position, a null terminator? - beq shftln_end1 ; Yes, so we're done. + beq @end3 ; Yes, so we're done. phy #2 ; No, so save the source position for later. txy ; Set our position to the destination. sta (ptr3), y ; Place the character from the source position, to the destination position. @@ -776,44 +775,44 @@ shftln_lp1: ply #2 ; Set our position back to the source. stb (ptr3), y ; Clear the character that is in the source. iny ; Increment the source position. - jmp shftln_lp1 ; Keep looping. -shftln_wrap: + jmp @dec_loop ; Keep looping. +@wrap: tax ; Use the ending line as a parameter for setbit. jsr setbit ; Set the wrap bit of the ending line. - jmp shftln_end2 ; We are done. -shftln_wrp1: + jmp @end5 ; We are done. +@wrap1: tax ; Use the ending line as a parameter for clrbit. jsr clrbit ; Clear the wrap bit of the ending line. - jmp shftln_end2 ; We are done. -shftln_end: + jmp @end5 ; We are done. +@end: lda (ptr3), y ; Is this character a null terminator? - bne shftln_nd0 ; No, so just find the end of the line. + bne @end1 ; No, so just find the end of the line. lda #$20 ; Yes, so convert it to a space for now. sta (ptr3), y ; -shftln_nd0: +@end1: jsr findend ; Find the ending line. sta d ; Save ending line for later. lda (ptr3), y ; Is this character a space? cmp #$20 ; - bne shftln_nd1 ; No, so skip the conversion. + bne @end5 ; No, so skip the conversion. lda #0 ; Yes, so convert it back to zero. sta (ptr3), y ; -shftln_nd1: +@end2: lda d ; Get the ending line. cmp scr_row ; Is the ending line greater than the starting line? - beq shftln_end2 ; No, so we're done. - bcs shftln_wrap ; Yes, so set the wrap bit. - jmp shftln_end2 ; No, so we're done. -shftln_end1: + beq @end5 ; No, so we're done. + bcs @wrap ; Yes, so set the wrap bit. + jmp @end5 ; No, so we're done. +@end3: jsr findend ; Find the ending line. cpb #0 ; Is the remainder zero? - beq shftln_nd2 ; Yes, so check if the ending line is greater than the starting line. - jmp shftln_end2 ; No, so we're done. -shftln_nd2: + beq @end4 ; Yes, so check if the ending line is greater than the starting line. + jmp @end5 ; No, so we're done. +@end4: cmp scr_row ; Is the ending line greater than the starting line? - beq shftln_end2 ; No, so we're done. - bcs shftln_wrp1 ; Yes, so clear the wrap bit. -shftln_end2: + beq @end5 ; No, so we're done. + bcs @wrap1 ; Yes, so clear the wrap bit. +@end5: rts ; End of shftln. esc: @@ -864,35 +863,36 @@ shftesc_end: isup: lda c ; Load the escape code into the accumulator. cmp #'A' ; Did the user press the up arrow key? - bne isup_done ; No, so we're done. + bne @end ; No, so we're done. lda scr_row ; Yes, but is the cursor at the top of the screen? - beq isup_scrl ; Yes, so check if we need to scroll. -isup_2: + beq @scroll ; Yes, so check if we need to scroll. +@check2: lda c ; No, so load the escape code back into the accumulator. cmp #'A' ; Did the user press the up arrow key? beq up ; Yes, so move the cursor up. - jmp isup_done ; No, so we're done -isup_scrl: + jmp @end ; No, so we're done. +@scroll: lda scr_str ; Are we at the top of the screen buffer? - beq isup_done ; Yes, so we're done. + beq @end ; Yes, so we're done. jsr scrl_up ; No, so scroll up. lda #1 ; Tell the escape routine that we were successful. sta d ; +@end: isup_done: rts ; End of isup. isdown: lda c ; Load the escape code into the accumulator. cmp #'B' ; Did the user press the down arrow key? - bne isdown_done ; No, so we're done. + bne @end ; No, so we're done. lda scr_row ; Yes, so start checking the y coordinate of the cursor. cmp #maxrow ; Is the cursor at the bottom of the screen? - beq isdown_scrl ; Yes, so scroll down. + beq @scroll ; Yes, so scroll down. lda c ; No, so load the escape code back into the accumulator. cmp #'B' ; Did the user press the down arrow key? beq down ; Yes, so move the cursor down. - jmp isdown_done -isdown_scrl: + jmp @end ; No, so we're done. +@scroll: lda scr_row ; Save the cursor's row number. sta scr_trow ; lda scr_col ; Save the cursor's column number. @@ -904,42 +904,44 @@ isdown_scrl: sta scr_col ; lda #1 ; Tell the escape routine that we were successful. sta d ; +@end: isdown_done: rts ; End of isdown. isright: lda c ; Load the escape code into the accumulator. cmp #'C' ; Did the user press the right arrow key? - bne isright_dne ; No, so we're done. + bne @end2 ; No, so we're done. lda scr_col ; Yes, so start checking the x coordinate of the cursor. cmp #maxcol ; Is the cursor at the far right of the screen? - beq isright_wrp ; Yes, so check if this is a wrapped line. + beq @wrap ; Yes, so check if this is a wrapped line. jmp right ; No, so move the cursor right, like normal. -isright_wrp: +@wrap: inc scr_row ; Move down a row. jsr getbit ; Is the current line, a wrapped line? - bcs wrap_inc ; Yes, so leave the cursor where it is. + bcs @incr ; Yes, so leave the cursor where it is. dec scr_row ; No, so move the cursor back up a row. - jmp isright_dne ; We are done. -isright_scr: + jmp @end2 ; We are done. +@scroll: lda scr_str ; Are we at the top of the screen buffer? - beq isright_end ; Yes, so we're done. + beq @end ; Yes, so we're done. lda #1 ; No, so scroll down. sta wrapped ; Set the wrapped flag. jsr scrl_down ; Scroll down. - jmp isright_end ; We are done. -wrap_inc: + jmp @end ; We are done. +@incr: lda #0 ; Set the cursor to the far left of the screen. sta scr_col ; lda scr_row ; Get the current row number. cmp #maxrow ; Are we at the bottom of the screen? - beq isright_nd2 ; No, so we're done. - bcs isright_scr ; Yes, so check if we are scrolling down. - jmp isright_nd2 ; No, so we're done. -isright_end: + beq @end1 ; No, so we're done. + bcs @scroll ; Yes, so check if we are scrolling down. + jmp @end1 ; No, so we're done. +@end: dec scr_row ; Move back up a row. -isright_nd2: +@end1: jsr update_pos ; Update the cursor position. +@end2: isright_dne: lda #0 ; Unset the wrapped flag. sta wrapped ; @@ -948,40 +950,41 @@ isright_dne: isleft: lda c ; Load the escape code into the accumulator. cmp #'C' ; Did the user press right? - beq isleft_done ; Yes, so we're done + beq @end1 ; Yes, so we're done lda scr_col ; No, but is the cursor at the far left of the screen? - beq isleft_wrp ; Yes, so start checking if this is a wrapped line. + beq @wrap ; Yes, so start checking if this is a wrapped line. lda c ; No, so load the escape code back into the accumulator. cmp #'D' ; Did the user press the left arrow key? beq left ; Yes, so move the cursor left. - jmp isleft_done ; No, so we're done. -isleft_wrp: + jmp @end1 ; No, so we're done. +@wrap: jsr getbit ; Is the current line, a wrapped line? - bcs wrap_dec ; Yes, so wrap back up a line. - jmp isleft_done ; No, so we're done. -wrap_dec: + bcs @decr ; Yes, so wrap back up a line. + jmp @end1 ; No, so we're done. +@decr: lda scr_row ; Is the cursor at the top of the screen? - beq wrap_dec1 ; Yes, so don't move up a line. + beq @decr1 ; Yes, so don't move up a line. lda #1 ; No, so set the wrapped flag. sta wrapped ; dec scr_row ; Move the cursor up one line. -wrap_dec1: +@decr1: lda #maxcol ; Move the Cursor to the far right of the screen. sta scr_col ; lda #1 ; Tell the escape routine that we were successful. sta d ; lda scr_row ; Are we at the top of the screen? - beq isleft_scrl ; Yes, so check if we need to scroll. - jmp isleft_end ; No, so we're done. -isleft_scrl: + beq @scroll ; Yes, so check if we need to scroll. + jmp @end ; No, so we're done. +@scroll: lda wrapped ; Was the wrapped flag set somewhere else? - bne isleft_end ; Yes so we're done. + bne @end ; Yes so we're done. lda scr_str ; No, but are we actually at the top of the screen buffer? - beq isleft_done ; Yes, so we're done. + beq @end1 ; Yes, so we're done. jsr scrl_up ; No, so scroll up. - jmp isleft_done ; We are done. -isleft_end: + jmp @end1 ; We are done. +@end: jsr update_pos ; Update the cursor position. +@end1: isleft_done: lda #0 ; Unset the wrapped flag. sta wrapped ; @@ -1082,7 +1085,7 @@ getcol: sta scr ; to the screen. lda scr_col ; Get the cursor's x coordinate. div #10 ; Divide A by 10. - clc + clc ; adc #'0' ; Convert it to ascii, and sta scr ; print to the screen. tba ; Get the remainder. @@ -1103,26 +1106,26 @@ scrl_down: lda scr_row ; Get the cursor's line number. pha #1 ; Save it in the stack. lda wrapped ; Was the wrapped flag set? - beq scrldn_save ; Yes, so save the cursor position. -scrldn1: - jsr rdrw_row ; Redraw this row. + beq @save ; Yes, so save the cursor position. +@redraw: + jsr rdrw_row ; No, so redraw this row. lda wrapped ; Was the wrapped flag set? - beq scrldn_load ; Yes, so load the previous cursor position back. - jmp scrldn_end ; No, so we're done. -scrldn_save: + beq @load ; Yes, so load the previous cursor position back. + jmp @end ; No, so we're done. +@save: lda scr_col ; Get the cursor's column number. pha #1 ; Save it in the stack. - jmp scrldn1 ; Start redrawing the current row. -scrldn_load: + jmp @redraw ; Start redrawing the current row. +@load: pla #1 ; Get the cursor's previous column number back. sta scr_col ; -scrldn_end: +@end: pla #1 ; Get the cursor's previous line number back. sta scr_row ; jsr update_pos ; Update the cursor's position. lda #0 ; Clear the wrapped flag. sta wrapped ; -scrldn_done: +@end1: rts ; End of scrl_down. scrl_up: @@ -1146,37 +1149,37 @@ scrl_up: pla #1 ; sta scr_row ; jsr update_pos ; -scrlup_done: +@end: rts ; rdrw_row: lda #0 ; sta scr_col ; jsr update_pos ; -rdrow_st: +@loop: lda (ptr3), y ; - beq rdrow_inc ; + beq @incr ; sta scr ; -rdrow_inc: +@incr: inc scr_col ; lda (ptr3), y ; - beq rdrow_skip ; -rdrow_inc1: + beq @skip ; +@incr1: iny ; -rdrow_inc2: +@incr2: lda scr_col ; cmp #maxcol+1 ; - bcs rdrow_end ; - jmp rdrow_st ; -rdrow_skip: + bcs @end ; + jmp @loop ; +@skip: lda #' ' ; sta scr ; to the screen. - jmp rdrow_inc1 ; -rdrow_end: + jmp @incr1 ; +@end: lda #0 ; sta scr_col ; jsr update_pos ; -rdrow_done: +@end1: rts ; rdrw_ln: @@ -1187,17 +1190,17 @@ rdrw_ln: lda scr_col ; pha #1 ; jsr update_pos ; -rdrwln_lp: +@loop: lda scr_row ; cmp e ; - beq rdrwln_lp1 ; - bcs rdrwln_done ; -rdrwln_lp1: + beq @loop1 ; + bcs @end ; +@loop1: jsr rdrw_row ; -rdrwln_inc: +@incr: inc scr_row ; - jmp rdrwln_lp ; -rdrwln_done: + jmp @loop ; +@end: pla #1 ; sta scr_col ; pla #1 ; @@ -1210,21 +1213,21 @@ rdrwln_done: set_ptr: cpb #1 ; Are we setting the second pointer? - beq set_ptr2 ; Yes, so start setting it. + beq @ptr2 ; Yes, so start setting it. cpb #2 ; No, but are we setting the third pointer? - beq set_ptr3 ; Yes, so start setting it. -set_ptr1: + beq @ptr3 ; Yes, so start setting it. +@ptr1: stb.q ptr ; Reset the first pointer. sta.q ptr ; No, so set the first pointer. - jmp setptr_end ; We are done. -set_ptr2: + jmp @end ; We are done. +@ptr2: stb.q ptr2 ; Reset the second pointer. sta.q ptr2 ; Set the second pointer. - jmp setptr_end ; We are done. -set_ptr3: + jmp @end ; We are done. +@ptr3: stb.q ptr3 ; Reset the third pointer. sta.q ptr3 ; Set the third pointer. -setptr_end: +@end: rts ; End of set_ptr. ; Entry point for SuBAsm. -- cgit v1.2.3-13-gbd6f