diff options
Diffstat (limited to 'programs/sub-suite/print_char.s')
| -rw-r--r-- | programs/sub-suite/print_char.s | 147 |
1 files changed, 147 insertions, 0 deletions
diff --git a/programs/sub-suite/print_char.s b/programs/sub-suite/print_char.s new file mode 100644 index 0000000..e12461c --- /dev/null +++ b/programs/sub-suite/print_char.s @@ -0,0 +1,147 @@ +print_char: +; sta a ; Save the typed character for now. + pha ; Preserve the character. +; ldb #2 ; Make sure that set_ptr sets the third pointer. + lda.d #buffer ; Set the third pointer to the start of the screen buffer. + pha.q ; Push the pointer onto the stack. + lda sp+9 ; Get the character back. +; jsr set_ptr ; +; ldb #0 ; Set B to zero. +; tba ; Set the Accumulator to zero. +; lda a ; Get back the character. + cmp #$1B ; Did the user type an escape character? + beq esc ; Yes, so go check the escape code. + cmp #'\n' ; No, but did the user type a newline? + beq nl ; Yes, so handle the newline. + cmp #$C ; No, but did the user type Ctrl+L? + beq clr_scr ; Yes, so clear the screen. + cmp #19 ; No, but did the user type Ctrl+S? + beq en_step ; Yes, so enable clock/instruction stepping. + cmp #18 ; No, but did the user type Ctrl+R? + beq dis_step ; Yes, so disable clock/instruction stepping. + cmp #'\b' ; No, but did the user type a backspace? + beq bs ; Yes, so handle the backspace. + cmp #$7F ; No, but did they type Delete? + beq bs ; Yes, so treat it as a backspace. +printc: + lda #0 ; No, so start trying to print a character. + sta d ; + lda (sp+1), y ; Are we at the end of the string? + beq @save ; Yes, so just print the character. + lda b ; No, but was the flag set? + 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. + bra @shift ; Start shifting the line right. +@update: + lda scr_col ; Save the current column position for later. + sta scr_tcol ; +@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. +@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. + sta scr_row ; + lda scr_tcol ; Get the real column position back. + sta scr_col ; + jsr update_pos ; Update the cursor's position. + dec d ; + bra @save1 ; +@shift: + ldy.w scr_ptr3 ; + inc scr_ptr3 ; + tyx ; + dey ; + ldb #1 ; + stb d ; + jsr shftln ; + ldb #1 ; + stb d ; +; lda a ; + lda sp+9 ; + sta (sp+1), y ; store typed character into the input buffer. + lda scr_row ; + sta scr_trow ; + bra @update ; +@save: + ldb d ; + bne @update ; +@save1: +; lda a ; + lda sp+9 ; + sta (sp+1), y ; store typed character into the input buffer. +@incr: + inc scr_col ; Increment the cursor's x coordinate. + iny ; +@wrapped: + ldb #1 ; + stb f ; + ldb scr_col ; + cpb #maxcol+1 ; + bcs @scrolled ; +@print: + sta scr ; Echo typed character. + ldb f ; + beq @wrap ; + bra printc_end ; +@scrolled: + ldb scr_row ; + cpb #maxrow ; + bcs @scroll ; +@wrapped2: + ldb #0 ; + stb f ; + bra @print ; +@scroll: + sta scr ; Echo typed character. + clc ; + lda #1 ; + sta wrapped ; + jsr scrl_down ; +@wrap: + ldb #0 + stb scr_col ; + ldb scr_row ; + cpb #maxrow ; + bcs @wrap2 ; +@wrap1: + inc scr_row ; +@wrap2: + phx.w ; + clc ; + lda scr_row ; + adc scr_str ; + tax ; + jsr setbit ; + plx.w ; + jsr update_pos ; +printc_end: + pla.q ; Pull the pointer off the stack. + pla ; Pull the character off the stack. + and #0 ; Reset A. + rts ; + +nl: + lda #0 ; Reset A. + ldb (sp+1), y ; Is this character not a null terminator? + bne @scroll ; Yes, so don't overwrite it. + sta (sp+1), y ; No, so overwrite it. +@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 @incr ; No, so move down one line. + jsr scrl_down ; Yes, so scroll down one line. + bra @end ; We are done. +@incr: + inc scr_row ; Move the cursor down by one line. + jsr update_pos ; Update the cursor's position. +@end: + lda #'\n' ; Print the newline. + sta a ; + rts ; |