mirror of
https://github.com/cc65/cc65.git
synced 2024-07-23 03:28:58 +00:00
65 lines
1.3 KiB
ArmAsm
65 lines
1.3 KiB
ArmAsm
;
|
|
; Christian Groessler, October 2000
|
|
;
|
|
; This file provides the __sio_call function
|
|
; The function does a SIO call, it's not completely
|
|
; generic (e.g. transfer size is fixed), it's used
|
|
; to save space with _dio_read and _dio_write functions.
|
|
;
|
|
; unsigned char __fastcall__ _sio_call(_driveid_t drive_id,
|
|
; _sectnum_t sect_num,
|
|
; void *buffer,
|
|
; unsigned int sio_val);
|
|
; _driveid_t - 8bit
|
|
; _sectnum_t - 16bit
|
|
; sio_val is (sio_command | sio_direction << 8)
|
|
;
|
|
|
|
.export __sio_call
|
|
.include "atari.inc"
|
|
.import popa,popax
|
|
.import sectsizetab
|
|
|
|
.proc __sio_call
|
|
|
|
sta DCOMND ; set command into DCB
|
|
stx DSTATS ; set data flow directon
|
|
jsr popax ; get buffer address
|
|
sta DBUFLO ; set buffer address into DCB
|
|
stx DBUFHI
|
|
jsr popax
|
|
sta DAUX1 ; set sector #
|
|
stx DAUX2
|
|
jsr popa
|
|
cmp #NUMDRVS
|
|
bcs _inv_dev ; invalid device #
|
|
adc #1
|
|
sta DUNIT ; unit number (d1,d2,d3,...)
|
|
sbc #0
|
|
asl a
|
|
tax
|
|
lda sectsizetab,x
|
|
sta DBYTLO ; low byte of bytes to transfer
|
|
lda sectsizetab+1,x
|
|
sta DBYTHI ; high byte of bytes to transfer
|
|
lda #$31 ; D1 (drive_id == 0) has id $31
|
|
sta DDEVIC
|
|
lda #15
|
|
sta DTIMLO ; value got from DOS source
|
|
|
|
jsr SIOV ; execute
|
|
|
|
ldx #0
|
|
lda DSTATS
|
|
bmi _req_err ; error occurred
|
|
txa ; no error occurred
|
|
_req_err:
|
|
rts
|
|
|
|
_inv_dev:
|
|
ldx #0
|
|
lda #NONDEV ; non-existent device error
|
|
rts
|
|
|
|
.endproc
|