Improved device I/O under DOS 3.3

Certain scenarios (e.g. not running any Applesoft program at all since booting DOS 3.3) can make DOS 3.3 consider cc65 device input (e.g. getchar()) that reads a CR interpreting the command in the keyboard buffer. Setting the hibyte of the Applesoft currently executed line number to some value <> $FF (beside setting the input prompt to some value <> ']') makes DOS 3.3 understand that we're not in intermediate mode and that therefore I/O not preceded with ctrl-d mustn't be fiddled with (see DOS 3.3 routine at $A65E).
This commit is contained in:
Oliver Schmidt
2020-12-19 19:54:12 +01:00
parent 59c58acbe3
commit 0f4cb443b4
2 changed files with 7 additions and 3 deletions

View File

@@ -15,6 +15,7 @@ PROMPT := $33 ; Used by GETLN
RNDL := $4E ; Random counter low
RNDH := $4F ; Random counter high
HIMEM := $73 ; Highest available memory address+1
CURLIN := $75 ; Current line number being executed
;-----------------------------------------------------------------------------
; Vectors