IBM 5150

LOC OBJ LINE SOURCE
EE52: 800£410080
2639
OR o ISKETTE_ST ATUS. TIME_OUT
££57 59 2640 POP CX
EE58 SA 2641
POP OX
; SET ERROR CODE AND RESTORE REGS
EES9 56
2.642
POP AX
; DISCARD THE RETUF!N ADDRESS
EESA F9 2643 STC
; INDICATE ERROR TO CALLER
EES9 C3
2644
Rn
2645
EESC
2646 J25:
EESC 33C9
2647
XOR cx.cx
; RESET THE COUUT
EESE
2648
J26:
EESE EC
~649 IN
.u,ox ; GET THE STATUS
EESF AB80 2650 TEST AL.OBOH
J IS IT READY
J""
r""\
fE61 7504 2651 J27
I YES. GO OUTPUT
fE63 E2F9 2652 LOOP J2.
J COUNT omm AHD TRY AGAIN
fE65 EBEB
2653
J"P J2'
J ERROR CONDITION
fE67
2654 J2:7: ; OUTPUT
fE67 84C4
2655
t10V
AL,AH • GET BYTE TO OUTPUT
E£69 BAF501 2656 DX,03F5H
; DATA PORT
""V
Efbe EE 2657 OUT
OX.AL
; OUTPUT THE BYTE
EE60 59
2:658 POP CX
; RECOVER REGISTERS
fE6E 5A
2659 POP OX
EE6F C3 2.660
Rn
; CY = 0 FROM TEST INSTRUCTION
2661 NEt_OUTPUT
ENOP
2662
; --- ----- --- ------ ---- -- -- --- --- -- ---------
2663 ; GET_PARM
2664
I
THIS ROUTINE fETCHES THE IHOEXED POINTER FROM
2665
I
THE DISK_BASE BLOCK POINTED AT BY THE DATA
2666
I
VAF!IABLE DISK_POINTER
2667 ; A eYTE FROM THAT TABLE IS THEN HOVED INTO AH,
2668 ; THE INDEX OF THAT BYTE BEING THE PARrt IN ex
2669 ; ENTRY --
2670
BX = INDEX OF BYTE TO BE FETCHED * 2
2671
IF THE lOW BIT OF ex IS ON. THE BYTE IS IMMEDIATELY
2672
OUTPUT TO THE NEC CONTROLLER
2673
EXIT --
2674
AH = THAT BYTE fROM BLOCK
2675
; - -------------------------------------------
r""\
EE70 2676 GET_PARl1
PROC t~EAR
E£70 IE 2677
PUSH
as
SAVE SEGMENT
EE71 2BCO 2678
SUB
AX.AX J ZERO TO AX
EE73 8E08 2679
"OV
OS,AX
2680
ASSUME OS:ABSO
E£75 C5367800 2681
LOS 51 ,DISK_POINTER ; POINT TO BLOCK
EE79 DIES
2682 SHR ax,l ; DIVIDE BX BY 2. AND SET flAG FOR EXIT
EE7B 8A20
2683
"OV
AH,lSI+BXl ; GET THE WORD
EE7D IF
2684 POP
OS
j RESTORE SEGMENT
268S ASSUME OS:OATA
EE7E
72C4 2686
JC NEC_OUTPUT
; IF FLAG SET, OUTPUT TO CONTROLLER
EE80 C3
2687 RET
; RETURN TO CALLER
2688
GET_PARI1 ENOP
2689
;--------------------------------------------
2690 ; SEEK
2691
THIS ROUTINE WILL MOVE THE HEAD ON THE NAMED DRIVE
2692
TO THE NAMED TRACK. IF THE DRIVE HAS NOT BEEN ACCESSED
2693 SINCE THE DRIVE RESET COMMAND WAS ISSUED, THE DRIVE WILL BE
2694 RECALIBRATED.
2695 ; INPUT
.2:696
(DU = DRrVE TO SEEK ON
2697 (CH) =TRACK TO SEEK TO
2698 ; OUTPUT
2699
CY = 0 SUCCESS
2700
CY = 1 FAILURE -- DISKETTE_STAn../S SET ACCORDINGLY
2701
(AX I DESTROYED
2702
; -- - -------------------- ----------- ----- - ----
EE81
2703
SEEK
PROC
HEAR
EE8l· 8001 2704
MV AL,1 ; ESTABLISH MASK fOR RECAL TEST
EE63 51 2705
PUSH CX
; SAVE INPUT VALUES
EE84 8ACA 2706 CL,OL ; GET DRIVE VALUE INTO CL
r""\
""V
EE86
D2CO 2707
ROL AL,CL ; SHIFT IT BY THE DRIVE VALUE
EE88 59
2708
POP CX
; RECOVER TRACK VALUE
EE89 84063EOO
2709 TEST AL,SEEK_STATUS ; TEST FOR REeAL REQUIRED
EE8D
7513 2710 JIlZ
J2.
-; NO_RECAl
EE8F 06063EOO 2711 OR SEEK_STATUS,AL ; TURn ON THE HO RECAL BIT IN FLAG
EE93
6407
2712
"OV
AH ,07H i RECALIBRATE COMMAND
EE95 E6ACFF
2713 CALL NEC_OUTPUT
EE98 6AE2 2714-
"OV
AH,DL
EE9A E6A7FF
2715 CALL tlEC_OUTPUT
; OUTPUT THE DRIVE HUMBER
A-37