1
0
mirror of https://github.com/cc65/cc65.git synced 2024-11-18 00:07:21 +00:00
cc65/libsrc/apple2/cgetc.s
uz 53dd513176 This commit was generated by cvs2svn to compensate for changes in r2,
which included commits to RCS files with non-trunk default branches.


git-svn-id: svn://svn.cc65.org/cc65/trunk@3 b7a2c559-68d2-44c3-8de9-860c34a00d81
2000-05-28 13:40:48 +00:00

25 lines
468 B
ArmAsm

;;
;; Kevin Ruland
;;
;; char cgetc (void);
;;
;; If open_apple key is pressed then the high-bit of the
;; key is set.
.export _cgetc
.include "apple2.inc"
_cgetc:
lda KEY_STROBE
bpl _cgetc ; if < 128, no key pressed
;; At this time, the high bit of the key pressed
;; is set
sta CLEAR_KEY_STROBE; clear keyboard strobe
bit OPEN_APPLE ; check if OpenApple is down
bmi pressed
and #$7F ; If not down, then clear high bit
pressed:
ldx #0
rts