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Amazing #02
14 июля 1998 |
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Assembler - SH-93: Procedures for direct work with the floppy drive controller.
(C) 1998 by Dr. Serg
Music by Spider
; Sector write procedure
; Entry: BC-trek, sect
; Recording from addresses HL
; (WrMode) keeps a record type sector
; 00 bit 2 is set (# FB)
; 10100h00
; # FF bit 2 set (# F8)
, Output: A = 0 OK.v HL-next addres
; A = a positioning error
; A = 2 error records
; After the disk status register.
, Is rewritten by (ErrWG)
, With type 2 error is repeating
; Attempt to read (PowtRDS) raz.pri this
; Increasing. value (Bader) 1
WrSect ld a, (WrMode)
ld ix, Wrseccom
res 0, (ix +1)
and a: jr z, Wrsec1
set 0, (ix +1)
Wrsec1 ld de, PowtRDS
ld a, (de): inc de
ld (de), a
ld (Wrsec6 +1), hl
ld a, -1
call Posic
and a
jr nz, Wrsec3
Wrsec2 push bc
ld a, c
ld c, # 5f
call Dos1; Register sector
ld c, # 1f
Wrseccom ld a,% 10100000
call Dos1; command register
ld c, # 7f
ld ix, # 3fba
call Dos2; write cycle
ld ix, # 3c30
call Dos2
ld (ErrWG), a; registration status
push hl
Wrsec6 ld de, 0
inc de
and a
sbc hl, de
pop hl
pop bc
jr z, Wrsec4; not write
and% 11111111
jr nz, Wrsec4
xor a
jr Wrsec5
Wrsec4 ld hl, (Baderr)
inc hl
ld (Baderr), hl
ld hl, (Wrsec6 +1)
ld a, (PowtRDS +1)
dec a
ld (PowtRDS +1), a
ld a, 2
jp m, Wrsec5
jr Wrsec2
Wrsec3 ld a, 1
Wrsec5 out (# fe), a
ret
; Procedure readout sector
; Entry: BC-trek, sect
; Reading is made at HL
, Output: A = 0 HL-len load data (128,256 ..)
; A = a positioning error
; A = 2 error load data
; After the disk status register.
, Is rewritten by (ErrWG)
, With type 2 error is repeating
; Attempt to read (PowtRDS) n raz.pri this
; Increasing. value (Bader) 1
Rd1Sec ld de, PowtRDS
ld a, (de)
inc de
ld (de), a
ld (Rdsec6 +1), hl
ld a, -1
call Posic
and a
jr nz, Rdsec3
Rdsec2 push bc
ld a, c
ld c, # 5f
call Dos1; Register sector
ld c, # 1f
ld a,% 10000000
call Dos1; command register
ld c, # 7f
ld ix, # 3fd5
call Dos2; cycle read
ld ix, # 3c30
call Dos2
ld (ErrWG), a; registration status
push hl
Rdsec6 ld de, 0
inc de
and a
sbc hl, de
pop hl
pop bc
jr z, Rdsec4; not read
and% 11011111
jr nz, Rdsec4
out (# fe), a
ret
Rdsec4 ld hl, (Baderr)
inc hl
ld (Baderr), hl
ld hl, (Rdsec6 +1)
ld a, (PowtRDS +1)
dec a
ld (PowtRDS +1), a
ld a, 2
jp m, Rdsec5
jr Rdsec2
Rdsec3 ld a, 1
Rdsec5 out (# fe), a
ret
WrMode DB 0
PowtRDS DB 10,0
Baderr DW 0
; Procedure of positioning the head
; Login: B - track number 0-159
;: A = 0 test position 1
; (0001 1h00)
;: A = 255 not verify 0
; Output: A = 0 O.K.
; A <> 0 Error, bit 7, a = 1 command is not
, Adopted
; Bit 4, a = 1 error on; zitsionirovaniya
; Bit 0, a = 1 controller
; Not ready to receive
; Changes IX, AF
; Service Registry => (ErrWG)
; When starting the engine pauses
; Opred.konstantoy => (DrPause)
Posic push bc
ld ix, posicC
and a
set 2, (ix +1)
jr z, posic3
res 2, (ix +1)
posic3 ld ix, posicex
push ix
; Ust.side
ld a, b
srl a
ld b, a
ld ix, # 1feb
jr nc, posic1
ld ix, # 1ff6
posic1 call Dos2
ld ix, # 3c30
call Dos2
bit 0, a
jr z, posic4
; SH not gotova.preryvanie Kamanda
ld a,% 11010000
ld c, # 1f
ld ix, # 2a53
jr posic1
; Checking motor rotation
, And the modification of const. delay
posic4 ld ix, 1
bit 7, a
jr z, posic5
ld ix, (DrPause)
posic5 ld (posicp +2), ix
ld a, b
ld c, # 7f
call Dos1; ust.nom.treka
posicC ld a,% 00011100; bit 2-way navigation key and check ..
ld c, # 1f
call Dos1; Track Search
ld ix, # 3c30; in a, (# 1f)
posic2 call Dos2
bit 0, a; is the command
jp nz, posic2
bit 7, a
ret nz; Emergency exit
; Drive worth!
bit 4, a
ret nz; error search
bit 3, a
ret nz; error control.
; Code (if CHECK)
ld (ErrWG), a
; Pause, if there was engine start
posicp ld ix, 0
posic6 dec ix
ld a, xl
or xh
jr nz, posic6
pop bc
pop bc
ret
posicex ld (ErrWG), a
pop bc
ret
; Procedure to pass in TR.DOS
; On # 2A53: OUT (BC), A: RET
Dos1 ld ix, # 2a53; out (c), a: ret
Dos2 push ix
jp # 3d2f
ErrWG DB 0
DrPause DW # A000
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