cc65/libsrc/atari/dio_stc.s

71 lines
1.6 KiB
ArmAsm

;
; Christian Groessler, October 2000
;
; this file provides the _dio_log_to_phys function
; (previously called _dio_snum_to_chs, so the filename)
;
; on the Atari this function is a dummy, it returns
; cylinder and head 0 and as sector the sectnum it got
;
; unsigned char __fastcall__ dio_log_to_phys(dhandle_t handle,
; unsigned *sectnum, /* input */
; dio_phys_pos *physpos); /* output */
;
; dhandle_t - 16bit (ptr)
;
.export _dio_log_to_phys
.include "atari.inc"
.importzp ptr1,ptr2,ptr3
.import popax,popptr1,___oserror
.proc _dio_log_to_phys
sta ptr2
stx ptr2+1 ; pointer to output structure
jsr popptr1 ; save pointer to input data
jsr popax
sta ptr3
stx ptr3+1 ; pointer to handle
ldy #sst_flag
lda (ptr3),y
and #128
beq _inv_hand ; handle not open or invalid
lda #0
tay
tax
sta (ptr2),y ; head
iny
sta (ptr2),y ; track (low)
iny
sta (ptr2),y ; track (high)
iny
lda (ptr1,x)
sta (ptr2),y
iny
inc ptr1
bne _l1
inc ptr1+1
_l1: lda (ptr1,x)
sta (ptr2),y
txa
ret:
sta ___oserror
rts ; return success
; invalid handle
_inv_hand:
ldx #0
lda #BADIOC
bne ret
.endproc