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Data Input Form

Photo by Marvin Meyer on Unsplash

Continuing the Lab 4, we are going to develop the option 2, data input form. The goal is to prompt the user to enter its name, address, city, province and postal code. Also, letting the user use up, down, left, and right arrows to navigate throughout the fields. After finishing the data input, a summary is presented at the end.

Using the ROM routines, wasn’t too hard to allow users to type data into the character display. Then, I decided to make the filed names with the same width, 14 characters, limiting the input to 40 characters. So, the user is not allowed to type in the first 14 and after 54 characters. When the user presses enter at the last field, the summary is shown. I could display the fixed message, but I couldn’t copy the inserted data. I’m still working on that, and I’ll update this post as soon I figure it out.

It is frustrating for me to spend days in basic problems that could be solved quickly using other languages. Assembly is not captivating me at all. Perhaps, this is a lesson that would make me a better developer. I believe in the SPO course and hope to use upper-level languages soon.

; ROM routines
define SCINIT $ff81 ; initialize/clear screen
define CHRIN $ffcf ; input character from keyboard
define CHROUT $ffd2 ; output character to screen
define SCREEN $ffed ; get screen size
define PLOT $fff0 ; get/set cursor coordinates
define X $f5
define Y $f6
define SCREEN_PTR $f7
define SCREEN_PTR_HI $f8
define save1 $10
jsr SCINIT
ldx #$00
ldy #$00
jmp print_form
cursor:
; delay the cursor so it can blink on high speed too
sec ; set PLOT to get mode (carry = 1)
jsr PLOT ; get the cursor position
eor #$80 ; reverse video
ldy #$00 ; clear y
sta (SCREEN_PTR),y ; save the changed char
rts ; return
handle_key:
cmp #$0d
beq handle_enter
jmp print
handle_enter:
ldy Y
cpy #$04 ; enter at the last line means all input is done
beq print_label
jmp print
print:
sec
jsr CHROUT ; print the char
jmp main
print_label:
ldx #$00
ldy #$06
clc ; set PLOT to set mode (carry = 0)
jsr PLOT ; set the cursor position
ldx #$00
ldy #$00
jmp print_label_loop
main:
sec ; set PLOT to get mode (carry = 1)
jsr PLOT ; get the cursor position
cpx #$0d ; limit 14 chars from left
bmi cursor_limit_x_min
cpx #$37 ; limit 40 chars of input
bpl cursor_limit_x_max
cpy #$05 ; limit the cursor to the form area
bpl cursor_limit_y_max
jsr cursor ; blink cursor - reverse video
jsr cursor ; blink curosr - reverse it back
jsr CHRIN ; load the typed key into A
bne handle_key ; if some key was pressed
jmp main
print_label_loop:
lda label,y
beq cursor_reset
jsr CHROUT
iny
bne print_label_loop
print_form:
lda form,y
beq cursor_reset
jsr CHROUT
iny
bne print_form
set_cursor:
clc ; set PLOT to set mode (carry = 0)
jsr PLOT ; set the cursor position
jmp main
cursor_limit_x_min:
ldx #$0d
jmp set_cursor
cursor_limit_x_max:
ldx #$36
jmp set_cursor
cursor_limit_y_max:
ldy #$04
jmp set_cursor
cursor_reset:
ldx #$0d
ldy #$00
jmp set_cursor
form:
dcb "U","s","e","r", 32,"N","a","m","e", 32, 32,":",32,13
dcb "A","d","d","r","e","s","s", 32, 32, 32, 32,":",32,13
dcb "C","i","t","y", 32, 32, 32, 32, 32, 32, 32,":",32,13
dcb "P","r","o","v","i","n","c","e", 32, 32, 32,":",32,13
dcb "P","o","s","t","a","l", 32,"C","o","d","e",":",32,00
label:
dcb "Y","o","u","r", 32
dcb "o","r","d","e","r", 32
dcb "w","i","l","l", 32,
dcb "b","e", 32
dcb "d","e","l","i","v","e","r","e","d", 32
dcb "t","o",":",13,13,00
view raw spo-lab4b.s hosted with ❤ by GitHub

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