Driver Read / Write
--------------------
Specifications:
1) The length - 166 bytes.
2) TURBO read / write.
3) Floppy Drive A-D.
4) The bug - do not hang up, unlike
drivers, using chunks of MAGIC in
TR-DOS.
5) Does not reset when the PC TURBO
6) Works best on 5.03, 5.04 and
similar to them. At 1.5 can (?) Format
nut track ...
7) Called by the same # 3D13, C = 5 / 6.
8) Can work and allowed interrupt
vaniyah (but slow).
9) A simplified error handling: if the bits
0-6 Register # 1F dropped - it is believed
that there is no error. Otherwise - repeat.
A) You can change the Number of attempts to read
and writing. If the sector is still no problem
remains to (not written), it is determined but
measures under the head track and is
Repositioning (well, the word ...).
B) driver is necessary buffer for reading identification
fikatora sector (6 bytes).
C) not really been tested ...
ORG # 6000
ENT
; Written by Max / CBX / BD
; XAS Assembler, 06.08.98.
LD A, (# 5D16)
AND 3
LD (DRV +1), A; Number of drive.
LD HL, # 4000
LD DE, # 0000
LD BC, # 1805
CALL DRIVER
RET
DRIVER DI
LD IX, # 3FE5
LD A, # 80
BIT 0, C
JR NZ, LD_MODE
LD LX, # CA
LD A, # A0
LD_MODE LD (CMD +1), A
LD (PROC +2), IX
MAIN LD A, # 2C
BIT 0, D
JR NZ, DRV
LD A, # 3C
DRV OR 0
LD C, # FF
CALL REG
LD A, D
RRA
LD C, # 7F
CALL REG
LD A, # 18
CALL CMD_RDY
LD C, 8; Number of attempts.
ERR PUSH HL, BC
XOR A
LD (# 5CD6), A
OUT (# FE), A
LD A, E
INC A
LD C, # 5F
CALL REG
CMD LD A, # 80
CALL COMM
PROC LD IX, # 3FE5
LD C, # 7F
CALL TODOS
LD BC, CONT
PUSH BC
ONE LD BC, ONE
PUSH BC
LD B, # 01
PUSH BC
LD BC, # 2099
PUSH BC
JR DOS; Check # 1F.
CONT DI
POP BC, HL
LD A, (# 5CD6)
AND A
JR Z, NOERR
DEC C
JR NZ, ERR
OUT (# FE), A
PUSH HL
LD HL, TRK_BF
LD A, # C0
CALL CMD_RDY
POP HL
LD A, (TRK_BF)
LD C, # 3F
CALL REG
JR MAIN
NOERR INC H
INC E
BIT 4, E
JR Z, CNT
LD E, A
INC D
CNT DJNZ MAIN
EI
RET
COMM LD C, # 1F
REG LD IX, # 2A53
TODOS PUSH IX
DOS JP # 3D2F
CMD_RDY CALL COMM
LD C, # 7F
READY LD IX, # 3FE5
JR TODOS
TRK_BF EQU # 8000
P.S. In the last issue was my little article on
free download beysika.Privedennaya there a procedure designed
to read driver who, after his work in the HL shows the address
byte located after the last loaded sector.
If someone is using my prog,
Expect it.
*
Did you know that the work of the Player in STP
depends on the contents of the register A?
Explained:
ORG +6 JP PLAY; entry point for PLAY.
.......
PLAY DI
LD (XXXX), SP
LD D, 0 *
EXX
LD BC, XXXX
LD HL, XXXX
DEC (HL)
JP NZ, XXXX
LD (HL), 5; temp Mouzon.
INC HL
DEC (HL)
JP P, XXXX
LD HL, XXXX
OR (HL); Testing (HL) to zero.
JP Z, XXXX; Branching.
.......
NOTE: XXXX designated nonessential
in this case values.
As seen from the fragment
accumulator value is nowhere exposed. If the register A is not
zero - checking OR (HL) or in zhist not work ...
What this bug (?) Influences - is unknown, but the rumor
seems to be no differences.
Nevertheless, we can fix it (why?)
PLAYER, replacing marked '*' command LD D, 0 into two: XOR A:
LD D, A.
