--- /dev/null
+;
+; Maciej 'YTM/Elysium' Witkowiak
+; 2.7.2001
+;
+;
+; unsigned char __fastcall__ dio_phys_to_log(dhandle_t handle,
+; dio_phys_pos *physpos, /* input */
+; sectnum_t *sectnum); /* output */
+;
+; dhandle_t - 16bit (ptr)
+; sectnum_t - 16bit
+;
+
+ .export _dio_phys_to_log
+ .export sectab_1541_l, sectab_1541_h ; for log_to_phys
+ .import popax,__oserror
+ .importzp ptr1,ptr2,ptr3,tmp1,tmp2,tmp3,tmp4
+ .include "../inc/dio.inc"
+ .include "../inc/geossym.inc"
+ .include "../inc/const.inc"
+
+.proc _dio_phys_to_log
+ sta ptr1
+ stx ptr1+1 ; pointer to result
+
+ jsr popax
+ sta ptr2
+ stx ptr2+1 ; pointer to input structure
+
+ 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
+
+
+ ldy #diopp_head
+ lda (ptr2),y
+ bne _inv_data ; there is only head 0
+ ldy #diopp_track
+ lda (ptr2),y
+ beq _inv_data ; there is no track 0
+ sta tmp1
+ iny
+ lda (ptr2),y
+ bne _inv_data ; there are no more than 256 tracks
+ dec tmp1 ; normalize track to start from 0
+ ldy #diopp_sector
+ lda (ptr2),y
+ sta tmp2
+ iny
+ lda (ptr2),y
+ bne _inv_data ; there are no more than 256 sectors
+
+; tmp1 (int) holds track+sector, translate it using device info
+
+ ldy #sst_driveno
+ lda (ptr3),y
+ tay
+ lda driveType,y
+ and #%00000011 ; this is for RamDrive compatibility
+ cmp #DRV_1541
+ beq dio_cts1541
+ cmp #DRV_1571
+ beq dio_cts1571
+ cmp #DRV_1581
+ beq dio_cts1581
+
+ lda #DEV_NOT_FOUND ; unknown device
+ ldx #0
+ beq ret
+
+dio_ctsend:
+ ldy #1
+ lda tmp2
+ sta (ptr1),y
+ dey
+ lda tmp1
+ sta (ptr1),y
+
+ ldx #0
+ txa
+ret:
+ sta __oserror
+ rts ; return success
+
+; errors
+
+_inv_data:
+ lda #INV_TRACK
+ .byte $2c
+_inv_hand:
+ lda #INCOMPATIBLE
+ ldx #0
+ beq ret
+
+; device-depended stuff, tmp1=track-1, tmp2=sector
+
+dio_cts1541:
+ ldy tmp1
+ cpy #35
+ bcs _inv_data
+ lda sectab_1541_l,y
+ clc
+ adc tmp2
+ sta tmp1
+ lda sectab_1541_h,y
+ adc #0
+ sta tmp2
+ jmp dio_ctsend
+
+dio_cts1571:
+ lda tmp1
+ cmp #70
+ bcs _inv_data
+ cmp #35 ; last track of one side
+ bcs _sub35
+ jmp dio_cts1541 ; track <=35 - same as 1541
+
+_sub35:
+ sec
+ sbc #35
+ sta tmp1
+ jsr dio_cts1541 ; get offset on second side of disk
+ lda tmp1 ; add second side base
+ clc
+ adc #<683
+ sta tmp1
+ lda tmp2
+ adc #>683
+ sta tmp2
+ jmp dio_ctsend
+
+dio_cts1581:
+; 1581 has 80 tracks, 40 sectors each secnum=track*40+sector
+ ldx #0
+ stx tmp3
+ stx tmp4
+ lda tmp1
+ beq _nomult
+ cmp #80
+ bcs _inv_data
+
+; mul40 by Christian Groessler
+ sta tmp4
+ asl a
+ rol tmp3
+ asl a
+ rol tmp3 ; val * 4
+ adc tmp4
+ bcc L1
+ inc tmp3 ; val * 5
+L1: asl a
+ rol tmp3 ; val * 10
+ asl a
+ rol tmp3
+ asl a
+ rol tmp3 ; val * 40 = AX
+ ldx tmp3
+ sta tmp3
+ stx tmp4
+
+_nomult:
+ lda tmp2
+ clc
+ adc tmp3
+ sta tmp1
+ lda tmp4
+ adc #0
+ sta tmp2
+ jmp dio_ctsend
+
+.endproc
+
+.rodata
+
+sectab_1541_l:
+ .byte $00, $15, $2a, $3f, $54, $69, $7e, $93
+ .byte $a8, $bd, $d2, $e7, $fc, $11, $26, $3b
+ .byte $50, $65, $78, $8b, $9e, $b1, $c4, $d7
+ .byte $ea, $fc, $0e, $20, $32, $44, $56, $67
+ .byte $78, $89, $9a, $ab
+sectab_1541_h:
+ .byte $00, $00, $00, $00, $00, $00, $00, $00
+ .byte $00, $00, $00, $00, $00, $01, $01, $01
+ .byte $01, $01, $01, $01, $01, $01, $01, $01
+ .byte $01, $01, $02, $02, $02, $02, $02, $02
+ .byte $02, $02, $02, $02
projects / cc65 / blobdiff