Keyboard handling, "Type something:"

2022-05-01 14:24:09 -05:00
parent 02c75c3cae
commit f63344089a
6 changed files with 330 additions and 5 deletions
@@ -0,0 +1,131 @@
+.org 0x400
+screen: .equ 0x10000
+reg: .equ 16
+
+;;;;; Start
+    push on_key
+    setiv 5
+    setint 1
+    call clear_screen
+    call set_video
+    push msg
+    push screen
+    call print
+wfi_loop: hlt
+    jmpr @wfi_loop
+;;;;;
+
+set_video:
+    push 30
+    storew reg + 10
+    push 40
+    storew reg + 13
+    ret
+
+clear_screen:
+    push screen
+    #while
+    dup
+    lt screen + 40 * 30
+    #do
+    dup
+    swap 0
+    store
+
+    dup
+    add 40 * 30
+    swap 0b10010010
+    store
+
+    add 1
+    #end
+    pop
+    ret
+
+print: ; ( msg addr -- )
+    pushr
+    #while
+    dup
+    load
+    #do
+    dup
+    load
+    peekr
+    store
+    popr
+    add 1
+    pushr
+    add 1
+    #end
+    pop
+    popr
+    pop
+    ret
+
+on_key:
+    setint 1 ; this can be reentrant, doesn't hurt anything
+    call is_press ; check for press
+    #if
+        ; if is alpha, look up in map and print
+        dup
+        call is_alpha
+        #if
+        call to_alpha_char
+        call putc
+        #else
+        pop
+        #end
+    #else
+    ; TODO:
+    ;   if is punc, look up in punc map and print
+    ;   if shift, set shift flag
+    ;   if return inc cursor
+    ;   if backspace, clear cursor and dec
+    ; else release:
+    ;   if shift, clear shift flag
+    pop
+    #end
+    ret
+
+is_press: ; ( event -- key bool )
+    dup
+    and 0xff
+    swap
+    and 0xff00
+    ret
+
+is_alpha: ; ( key -- bool )
+    dup
+    gt 0x03
+    swap
+    lt 0x27
+    and
+    ret
+
+is_punc: ; ( key -- bool )
+    dup
+    gt 0x2b
+    swap
+    lt 0x39
+    and
+    ret
+
+to_alpha_char: ; ( key -- ch )
+    sub 0x04
+    add alpha_table
+    load
+    ret
+
+putc: ; ( ch -- ) (also modifies cursor)
+    loadw cursor
+    dup
+    pushr
+    store
+    popr
+    add 1
+    storew cursor
+    ret
+
+cursor: .db screen + 40
+msg: .db "Type something:\0"
+alpha_table: .db "abcdefghijklmnopqrstuvwxyz1234567890"