IBM PC CONVERTIBLE

= 0001
0000
0000
0001
0002
0005
0005
0007
0009
OOOB
0000
0010
0012
0015
0018
0018
OOIB
001B
ODIC
0010
OOIE
0020
0024
0025
0026
0026
0029
002A
002B
002C
002E
0032
0033
0034
0034
0035
0038
0030
0041
0045
FB
IE
E8 0000
OA E4
74 2B
FE CC
74 3A
80 FC 09
73 06
E8 0000 E
EB 40 90
E8 0000
FB
IF
55
8B EC
80 66 06
50
CF
E8 0000
FB
IF
55
8B EC
I NTERNALL Y REFERENCED ROUTINES:
INITIALIZE_STATUS INITIALIZES RTC REGISTERS A THRU D
UPD_IN_PR WAITS UNTIL CLOCK NOT BEING UPDATED
SELALRM SETS RTC ALARM TIME BYTES AND ENABLES
THE RTC ALARM
EXTERNALL Y REFERENCED ROUTI NES:
DDS
GELRTCNMI
PULRTCNMI
ENABLCNMI
DISABLE_NMI
ESTABLISH SEGMENT
ADDRESSES AND READS A RTC REGISTER
AH = REGISTER #, AL = DATA READ
ADDRESSES AND PUTS A RTC REGISTER
AH = REGISTER #, AL = DATA PUT
ENABLE NMI' S
DISABLE NMI'S
*********************************************************************
SELCF
EQU
01H
TOD_PROC
PROC FAR
STI
INTERRUPTS ON FOR TIMER
PUSH OS SAVE SEGMENT
CALL DDS SET DATA SEGMENT
;-------CHECK FOR FUNCTION REQUESTS 0 AND
1- - - - - - - - - - - - - - - - - - - - - - - - --
RTCCHKO:
OR AH,AH I F PARAMETER AH=O
JZ RTCO THEN READ TIMER
DEC AH
I F PARAMETER AH=l
JZ RTCI THEN SET TIME
CMP AH,9 CHECK IF VALID DATA PASSED IN AH
(0 <= AH <= 9)
JAE
TOD_NRET
NORMAL RETURN IF NOT VALID
CALL
DISABLE_NMI
DISABLE NMI' S
JMP RTCCHKl GO CHECK FOR OTHER FUNCTIONS
; ---- --- TOD_PROC NORMAL RETURN- ---- -----------------------------------
TOD_NRET:
CALL
ENABLE_NMI
RE-ENABLE NMI' S
TOO_RET:
STI ENABLE INTERRUPTS FOR TIMER
POP OS RECOVER SEGMENT
PUSH BP
MOV
BP ,SP
FE AND BYTE PTR SS: [BP+6], NOT SELCF
RST CARRY OF FLAGS I N STACK
POP BP
IRET ; RETURN WITH GOOD CODE (CF=O)
; ------- TOD_PROC ERROR RETURN---- -------- -------------- - ------- ---- ---
TOD_ERET:
CALL
ENABLE_NMI
STI ENABLE INTERRUPTS FOR TIMER
POP OS RECOVER SEGMENT
PUSH BP
MOV BP, SP
80 4E 06 01 OR BYTE PTR 55: [BP+6-,SELCF ; SET CARRY OF FLAGS
50 POP BP
CF IRET
; RETURN WITH ERROR CD (CF=l)
;-------G E T
T
MER OAT A----- FUNCTION DOH
------- --- - - - - --
RTCO:
FA CLI
DISABLE INTERRUPTS FOR READ
AO 0070 R MOV
AL, TIMER_OFL GET OVERFLOW, AND
C6 06 0070 R 00 MOV TIMER_OFL,O RESET THE FLAG
8B OE 006E R MOV CX, TIMEILHIGH
CX RETURNS TIMER_HIGH DATA
8B 16 006C R MOV OX, TIMEILLOW
OX RETURNS TIMER_LOW DATA
EB 04 JMP
TOD_RET
NORMAL RETURN WITH TMR DATA
;-------S E T T
M E
R---------------
FUNCTION
OlH --------------
2-156 ROM BIOS