IBM 5170 Technical Reference page 304

01F8 B20A
MOV DL,OAH TURN OFF PIE
OHA E8 018B R
CALL PORT INC
OlFD E4 71
IN AL, CMOS_PORT+l
01 FF 24 BF
AND AL,OBFIi
0201 50 PUSH AX
0202 B2 OA
MOV DL,OAH
0204 E8 018B R
CALL PORT INC
0207 58
POP A X ­
0208 E6 71 OUT CMOS_PORT+l,AL
O?OA c6 06 OOAO R 00
MOV RTC_WAIT_FLAG,O ; SET FUNCTION ACTIVE FLAG OFF
020F C5 3E 0098 R
LOS DI,DWORD PTR USER_FLAG; SET UP DS,DI TO POINT TO USER FLAG
0213 C6 0') 80
MOV BYTE PTR[Dlj,80H ; TURN ON USERS FLAG
0216 RTC_' NT_9
0216 58
POP
AX
GET I NTERRUPT SOURCE BACK
0217 A8 20
TEST AL,20H TEST FOR ALARM INTERRUPT
0219 74 02 JZ
RTC I NT 10 NO - GO AROUND
021B CD 4A INT TRANSFER TO USER ROUT
I
NE
4AH- ­
0210 RTC_INT_l0·
0210 BO 20 MOV
AL, EOI END OF I NTERRUPT TO 8259 - 2
021F E6 AO OUT
OAOH,AL
0221 E6 20 OUT
020H,AL AND TO 8259 - 1
0223 5F
POP
01 RESTORE REG I STERS
0224 5A
POP
OX
0225 58 POP
AX
0226 1 F POP as
0227 CF IRET
END OF INTERRUPT
0228 RTC_'NT ENDP
PAGE
; -- I NT 8 (LEVEL 0) ---------------------------------------------:
Tii 1 S ROUT I NE HANDLES THE T I MER I NTERRUPT FROM
CHANNEL 0 OF THE 8253 TIMER. INPUT FREQUENCY IS 1.19318 MHZ :
AND THE DIVISOR IS 65536, RESULTING IN APPROX. 18.2 INTERRUPTS:
EVERY SECOND.
THE INTERRUPT HANDLER MAINTAINS A COUNT OF INTERRUPTS SINCE
POWER ON TIME, WHICH MAY BE USED TO ESTABLISH TIME OF DAY.
THE INTERRUPT HANDLER ALSO DECREMENTS THE MOTOR CONTROL COUNT
OF THE DISKETTE, AND WHEN IT EXPIRES, WILL TURN OFF THE
DISKETTE MOTOR(s), AND RESET THE MOTOR RUNNING FLAGS.
THE INTERRUPT HANDLER WILL ALSO INVOKE A USER ROUTINE THROUGH
INTERRUPT lCH AT EVERY TIME TICK. THE USER MUST CODE A
ROUTINE AND PLACE THE CORRECT ADDRESS IN THE VECTOR TABLE.
;
-
--- --- -
--------------------------------------------------
-
----
:
0228 TIMER INT 1 PROC FAR
0228 FB
- STI
I NTERRUPTS BACK ON
0229 1E PUSH as
022A 50 PUSH
AX
022B
52
PUSH OX SAVE MACHINE STATE
022C E8 0000 E CALL 005 ESTABL I SH ADDRESSAB I L I TY
022F
FF 06 006C R INC
TIMER LOW INCREMENT T I ME
0233 75 04 JNZ
T4 -
TEST DAY
0235 FF 06 006E R INC T I MER_H I GH INCREMENT HIGH WORD OF TIME
0239 T4:
TEST DAY
0239
023E
83 3E 006E R 18
75 15
CMP
JNZ
TIMER HIGH,018H
T5 -
TEST-FOR COUNT EQUALLI NG 24 HOURS
01 SKETTE_CTL
0240
0246
81 3E 006C R OOBO
75 00
CMP
JNZ
~~
MER_LOW, OBOH
T I MER HAS GONE 24 HOURS
0248
2B CO
SUB AX,AX
024A A3 006E R MOV TIMER HIGH,AX
0240 A3 006C R MOV TIMER-LOW,AX
0250 c6 06 0070 R 01 MOV TIMER=OFL,l
;------ TEST FOR DISKETTE TIME OUT
0255
T5:
;
01 SKETTE_CTL
0255 FE OE 0040 R OEC MOTOR_COUNT
0259 75 OB
JNZ
T6 RETURN I
r
COUNT NOT OUT
025B 80 26 003F R Fa ANa MOTOR_STATUS,OFOH
;
TURN OFF MOTOR RUNNING BITS
0260 BO DC
MOV
AL,OCH
0262 BA 03F2
MOV
DX,03F2H
FDC CTL PORT
0265 EE OUT
DX,AL TURN OFF THE MOTOR
0266 T6: TIMER RET:
0266 CO lC INT
lCH
TRANSFER CONTROL TO A USER ROUT I NE
0268 BO 20 MOV
AL, EOI
026A E6 20 OUT
0201-l,AL END OF I NTERRUPT TO 8259
026C 5A POP
ox
0260
58
POP
AX
026E 1F POP as
RESET MACH I NE STATE
026F CF
IRET RETURN FROM INTERRUPT
0270 TIMER - I NT_l ENDP
I NT 5 ------------------------------------------------------------- ­
THIS LOGIC WILL BE INVOKED BY INTERRUPT 05H TO PRINT
THE SCREEN. THE CURSOR POSITION AT THE TIME THIS ROUTINE
IS INVOKED WILL BE SAVED AND RESTORED UPON COMPLETION. THE
ROUTINE IS INTENDED TO RUN WITH INTERRUPTS ENABLED.
I F A SUBSEQUENT' PRINT SCREEN KEY IS DEPRESSED DURING THE
TIME THIS ROUTINE IS PRINTING IT WILL BE IGNORED.
ADDRESS 50:0 CONTAINS THE STATUS OF THE PRINT SCREEN:
50:0 EITHER PR I NT SCREEN HAS NOT BEEN CALLED
OR UPON RETURN FROM A CALL THIS INDICATES
A SUCCESSFUL OPERATION.
=1 PR I NT SCREEN I SIN PROGRESS
=255 ERROR ENCOUNTERED OUR I NG PR I NT I NG
ASSUME CS:CODE,DS:XXDATA
0270 PR I NT _SCREEN_l PROC
FAR
0270 FB STI !",UST RUN WITH INTERRUPTS ENABLED
0271 lE PUSH as MUST USE 50:0 FOR DATA AREA STORAGE
0272 50 PUSH AX
0273 53 PUSH
BX
0274 51 PUSH CX WILL USE THIS LATER FOR CURSOR LIMITS
0275 52
PUSH
OX WILL HOLD CURRENT CURSOR POS I T I ON
0276 B8 ---- R
MOV
AX,XXDATA HEX 50
0279 8E 08 MOV
DS,AX
027B 80 3E 0000 R 01
CMP
STATUS_BYTE,l SEE I F PR I NT ALREADY I N PROGRESS
0280 74 5F
JZ
EXIT JUMP IF PR I NT ALREADY I N PROGRESS
0282 C6 06 0000 R 01 MOV STATUS BYTE,l INDICATE PRINT NOW IN PROGRESS
0287 B4 OF
MOV
AH,15 -
WI LL REQUEST THE CURRENT SCREEN MODE
0289 CD 10
INT 10H [ALj=MODE
; [AH}=NUMBER COLUMNS/LINE
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5-162 BIOS 2