Allow to influence the user abort check.

It's imho in general a pretty unfortunate design to have IP65 check the keyboard during blocking operations. Rather it should call back into the application and have that decide what type of user abort it wants to offer.

Anyhow I don't want to change all that - at least not now. Therefore I just added the option to influence which key is considered the abort key - and provide a key value that isn't actually used and as such disables the abort check.

drivers/a2input.s

@@ -2,10 +2,18 @@
 .export check_for_abort_key
 .export get_key_if_available
 .export get_key_ip65
+.export abort_key
+.exportzp abort_key_default = $9b
+.exportzp abort_key_disable = $80
 
 .import ip65_process
 
 
+.data
+
+abort_key: .byte $9b            ; ESC
+
+
 .code
 
 ; use Apple 2 monitor ROM function to read from keyboard
@@ -31,12 +39,12 @@ got_key:
   and #$7f
   rts
 
-; check whether the escape key is being pressed
+; check whether the abort key is being pressed
 ; inputs: none
-; outputs: sec if escape pressed, clear otherwise
+; outputs: sec if abort key pressed, clear otherwise
 check_for_abort_key:
   lda $c000                     ; current key pressed
-  cmp #$9b
+  cmp abort_key
   bne :+
   bit $c010                     ; clear the keyboard strobe
   sec

drivers/atrinput.s

@@ -4,14 +4,18 @@
 .export check_for_abort_key
 .export get_key_if_available
 .export get_key_ip65
+.export abort_key
+.exportzp abort_key_default = 0
+.exportzp abort_key_disable = 0
 
 .import ip65_process
 
 
 .data
 
-iocb:  .byte 0
-kname: .byte "K:",155
+abort_key: .byte 0              ; ???
+iocb:      .byte 0
+kname:     .byte "K:",155
 
 
 .code
@@ -63,9 +67,9 @@ get_key_ip65:
   beq get_key_ip65
   rts
 
-;check whether the ??? key is being pressed
+;check whether the abort key is being pressed
 ;inputs: none
-;outputs: sec if ??? pressed, clear otherwise
+;outputs: sec if abort key pressed, clear otherwise
 check_for_abort_key:
   ; TODO: implement actual check
   clc

drivers/c64input.s

@@ -2,10 +2,18 @@
 .export check_for_abort_key
 .export get_key_if_available
 .export get_key_ip65
+.export abort_key
+.exportzp abort_key_default = $3f
+.exportzp abort_key_disable = $ff
 
 .import ip65_process
 
 
+.data
+
+abort_key: .byte $3f            ; RUN/STOP
+
+
 .code
 
 ; use C64 Kernel ROM function to read a key
@@ -14,8 +22,9 @@
 get_key:
   ldy #0
   sty $cc                       ; cursor on
+@loop:
   jsr get_key_if_available
-  beq get_key
+  beq @loop
   ldy #1
   sty $cc                       ; cursor off
   rts
@@ -32,18 +41,18 @@ get_key_ip65:
   beq get_key_ip65
   rts
 
-; check whether the RUN/STOP key is being pressed
+; check whether the abort key is being pressed
 ; inputs: none
-; outputs: sec if RUN/STOP pressed, clear otherwise
+; outputs: sec if abort key pressed, clear otherwise
 check_for_abort_key:
   lda $cb                       ; current key pressed
-  cmp #$3F
+  cmp abort_key
   bne @not_abort
 @flush_loop:
   jsr get_key_if_available
   bne @flush_loop
   lda $cb                       ; current key pressed
-  cmp #$3F
+  cmp abort_key
   beq @flush_loop
   sec
   rts

drivers/vic20input.s

@@ -2,10 +2,18 @@
 .export check_for_abort_key
 .export get_key_if_available
 .export get_key_ip65
+.export abort_key
+.exportzp abort_key_default = $18
+.exportzp abort_key_disable = $ff
 
 .import ip65_process
 
 
+.data
+
+abort_key: .byte $18            ; RUN/STOP
+
+
 .code
 
 ; use Vic 20 Kernel ROM function to read a key
@@ -14,8 +22,9 @@
 get_key:
   ldy #0
   sty $cc                       ; cursor on
+@loop:
   jsr get_key_if_available
-  beq get_key
+  beq @loop
   ldy #1
   sty $cc                       ; cursor off
   rts
@@ -32,18 +41,18 @@ get_key_ip65:
   beq get_key_ip65
   rts
 
-; check whether the RUN/STOP key is being pressed
+; check whether the abort key is being pressed
 ; inputs: none
-; outputs: sec if RUN/STOP pressed, clear otherwise
+; outputs: sec if abort key pressed, clear otherwise
 check_for_abort_key:
   lda $cb                       ; current key pressed
-  cmp #$18
+  cmp abort_key
   bne @not_abort
 @flush_loop:
   jsr get_key_if_available
   bne @flush_loop
   lda $cb                       ; current key pressed
-  cmp #$18
+  cmp abort_key
   beq @flush_loop
   sec
   rts