IBM 5150 Hardware Reference Manual page 232

LOt OBJ LINE SOURCE
fFOZ E605
fF04 8;'C4
EFOb E60S
EFDa 59
EF09 58
EFOA 03Cl
fFoe S9
EFOD B002
EFOF E60A
EFll C3
EFI2
Eft2: E81EOO
EFlS 7214
EFI? 8408
Ef19 E828FF
EFtC EMCOD
EFIF 720A
EF21 A04200
EF24 2460
EF26 3e60
EF2:6 7<+02
EFlA Fe
EF2B
EF2B C3
EF2:C
EF2C 800E410040
Enl F9
EF32 C3
EF33
EF33 FB
EF34
53
Ens 51
EFl6 8302
EF38 33C9
EnA
EF3A F6063E0080
EF3F 750C
EF41 E2F7
EF43 FECB
EF45 7SF3
EF47 800E410080
EF4C F9
EF40
EF40 9C
EF4E 80263E007F
EF53 9D
EF54 59
EF55 58
EF56 C3
OUT DNA+5,Al
MOV
AL,AH
OUT
DMA+5,AL
POP CX
POP
AX
ADO
Ax.ex
POP CX
2800 MOV Al,2 ; MODf FOR 8Z37
2801 OUT DMA+IO ,AL
; IUITIAlIZE THE DISKETTE CHANNEL
2:802 RET ; RETURN TO CALLER. eFl SET BY ABOVE IF ERROR
,e03
DNA_SETUP ENIlP
2804 ; --------------­ -----------------­ - ---------­
2805
j
CHK_STAT_2
2806 THIS ROUTINE HANDLES THE INTERRUPT RECEIVED AFTER
2607 A RECALIBRATE. SEEK, OR RESET TO THE ADAPTER.
2606 THE ItITERRUPT IS WAITED FOR. THE INTERRUPT STATUS SENSED.
2609 AUQ THE RESULT
RETUR~IED
TO THE CALLER.
2810 INPUT
2&11 NONE
2612 ; OUTPUT
2813
ty ; a
SUCCESS
2814 CY ;
1
FAILURE -­ ERROR IS IN DISKETTE_STATUS
2815
(AX)
DESTROYED
2816 ; --­ --------­ ---------------­ -----­ ---------­
2817 CHK_STAT_, PROC NEAR
2818
CALL WAIT_INT ; WAIT FOR THE INTERRUPT
2819
JC J34
; IF ERROR, RETURN IT
2820
MOV
AH,OBH
; SENSE INTERRUPT STATUS COMMAND
2521 CALL NEC_OUTPUT
2822 CALL RESULTS ; READ IN THE RESULTS
2523 JC
J34
; CHK2_RETURN
2824
MOV Al,t4EC_STATUS ; GET THE FIRST STATUS BYTE
2825
ANO
AL,060H ; ISOLATE THE SITS
2826 CHP AL,060H
; TEST FOR CORRECT VALUE
2827
JZ J3S i
IF ERRO~.
GO MARK
IT
28,8
CLC ; GOOD RETURN
2829 J34:
2830 RET ; RETURN TO CALLER
2831 J35:
; CHK,_ERROR
2832
OR
o
ISKETTE_ST A TUS, BAD_SEEK
2833
STC ; ERROR RETURN CODE
2834 RET
2835 CHK_STAT_2
ENDP
2836 ; ---­ ---------------------------------------­
2837 ; WAIT_INT
2838
nils
ROUTINE WAITS FOR AN INTERRUPT TO OCCUR
2839 A TIME OUT ROUTINE TAKES PLACE OU;;!WG THE WAIT, SO
2840 THAT AN ERROR MAY BE RETURUED IF THE DRIVE IS NOT READY
2841 ; INPUT
2842 ~lONE
2843 OUTPUT
2844 CY ; 0 SUCCESS
2845 CY
=
1
FAILURE -­ DISKETTE_STATUS IS SET ACCORDINGLY
2846
2847
(AX I DESTROYED
J------------------------------------------- ­
2848 WAIT_INT PROC' NEAR
2849 STI ; TURN ON INTERRUPTS, JUST IN CASE
2850 PUSH
ax
2851
PUSH CX
; SAVE REGISTERS
2852 MOV BL,2 ; CLEAR THE COUNTERS
2853
XOR
ex,cx
; FOR 2 SECOND WAIT
Z554 J36:
2855
TEST
SEEK_STATUS, HITJlAG ; TEST FOR INTERRUPT OCCURRING
2856 JHZ J37
2857 LOOP
J3'
COUNT DOWN WHILE WAITING
2858
DEC
BL SECOND LEVEl COUNTER
2859
Jt~Z J36
2860
OR
DISKETTE_STATUS, TIME_OUT
I
NOTHWG HAPPENED
2861
STC
ERROR RETURN
2862 J37:
2863 PUSHF ; SAVE CURRENT CARRY
2864
Arm
SEEK_STATUS,NOT INTJLAG ; TURN OFF INTERRUPT
FLAG
2865
POPF
; RECOVER CARRY
2866 POP
cx
2867 POP
ax
j
RECOVER REGISTERS
2868 RET ; GOOD RETURN CODE COMES FROM TEST INST
2869 WAlT_1NT ENDP
A-39