deac/osd-contiki
1
0
Fork 0
Code Issues Pull requests Releases Wiki Activity

status has been added for polling function.

Browse source
This commit is contained in:
matsutsuka 2007-09-19 12:47:19 +00:00
parent 8d7bb2119c
commit c99b7dc827
3 changed files with 20 additions and 13 deletions
Download patch file Download diff file Expand all files Collapse all files

19
platform/pc-6001/dev/rs232-asm.S
View file

@ -7,7 +7,7 @@
;;;
;;; @author Takahide Matsutsuka <markn@markn.org>
;;;
;;; $Id: rs232-asm.S,v 1.1 2007/09/11 12:12:59 matsutsuka Exp $
;;; $Id: rs232-asm.S,v 1.2 2007/09/19 12:47:19 matsutsuka Exp $
;;;
;; definitions of PC-6001 BIOS routines
@ -37,18 +37,25 @@ _rs232_arch_writeb:
ret
;; ---------------------------------
;; unsigned char rs232_arch_poll();
;; Stack; retl reth
;; AFBC__HL____
;; return input byte (zero if no input)
;; unsigned char rs232_arch_poll(unsigned char *stat);
;; Stack; retl reth statl stath
;; AFBCDEHL____
;; return input byte (*stat == 0 if no input)
;; ---------------------------------
_rs232_arch_poll:
ld a,#0x01
ld hl, #2
add hl, sp
ld e, (hl)
inc hl
ld d, (hl)
ld a, #0x01
ld (de), a
di
call #_char_input_sub ; read from buffer
ei
jr nz, _rs232_arch_poll_ret
xor a ; we have no data in the buffer
ld (de), a
_rs232_arch_poll_ret:
ld l, a
ret