Low Battery Check (Low_Bat - IBM PC CONVERTIBLE Technical Reference

0623 E8 076E R CALL NMLCYCLE CYCLE NMI , RESTORE INT FLAGS
0626 B9 64C8
MOV
CX,100*MS_DELAY
0629 E2 FE LOOP $
062B 24 OF
AND
AL, NOT SYNCENABLE TURN OFF SYNCS FOR POWER
0620 E6 75 OUT LCD_DATA,AL
,
062F 80 OE 0016 R 80 OR BIOS_STATUS,DSP_BLANKED ; SET DISPLAY BLANKED STATUS
0634 EB 11 JMP
SHORT RTCINL14 ; EXIT
TURN OFF SYSTEM
0636 DEACLSYSTEM:
0636 80 OE 0016 R 40 OR BIOS_STATUS,F_RESUME ; INDICATE FORCED RESUME MODE
063B E4 7F
IN AL,PWILSTAT GET POWER STAT/CNTL REG
0630 24 F7 AND AL, NOT HDWR_RESET TURN OFF RESET FLAG
063F OC 04 OR AL, EN_SUS_NMI ENABLE SYSTEM SUSPEND NMI
0641 E6 7F OUT PWILSTAT ,AL
0643 OC 02
OR AL, REQ_POFF REQUEST POWER OFF
0645 E6 7F OUT PWR_STAT ,AL
EXIT FROM RTC INTERRUPT
0647 RTCINLI4:
0647 E9 0050 R JMP NMIH_EXIT RETURN TO FIRST LEVEL HANDLER
064A RTCALARM_NMI ENDP
Low Battery Check (LOW_BAT_CHK)
064A
064A
064F
0651
0654
0656
0658
065A
065C
065E
0660
; **************************************************************************
LOW BATTERY CHECK
THIS ROUTINE CHECKS FOR A LOW BATTERY CONDITION AND IF DETECTED WILL ISSUE
A WARNING. THE LOW BATTERY WARNING WILL OCCUR AFTER TWO CONSECUTIVE LOW
BATTERY SENSES, NO EXTERNAL POWER SUPPLIED AND THE LOW BATTERY WARNING
FLAG IS ENABLED IN SYSTEM PROFILE. THE WARNING ISSUED WILL SOUND THREE
SHORT BEEPS, FLASH THE SCREEN ON AND OFF AT AN ONE SECOND INTERVAL AND
EXECUTE A PAUSE. THE PAUSE WILL HOLD UP ALL MAIN LEVEL PROCESSING AND
LOCK OUT NON- I NTERRUPT DR I VEN PROCESS I NG. ONCE TH E USER ACKNOWLEDGES THE
WARNING, EITHER BY PRESSING A KEY OR APPLYING EXTERNAL POWER, THE SCREEN
FLASHING WILL STOP AND MAIN LEVEL PROCESSING WILL CONTINUE.
AT SUCCESSIVE TWO MINUTE INTERVALS, THE LOW BATTERY WARNING WILL BE
REISSUED IF THE LOW BATTERY CONDITION STILL EXISTS OR EXTERNAL POWER HAS
NOT BEEN APPLIED. IF TWO MINUTES HAVE ELAPSED AND THE WARNING HAS NOT BEEN
ACKNOWLEDGED, THE APPLICATION WILL BE SUSPENDED AND THE SYSTEM POWERED OFF.
THIS ROUTINE IS CALLED BY THE RTCALAR~NMI ROUTINE EVERY ONE SECOND TO CHECK
ON THE BATTERY CONDITION. IF LOW BATTERY IS DETECTED, THIS ROUTINE WILL
CALL WAIT ON EXTERNAL EVENT. THIS WILL ALLOW THE SYSTEM TO SLEEP WHILE
WAITING FOR A KEY TO BE PRESSED. WHILE WAITING, THE ONE SECOND INTERRUPT CAN
OCCUR AGAIN CAUSING THE LOW BATTERY CHECK ROUTINE TO BE CALLED AGAIN. SO
THIS ROUTINE IS RECURSIVE.
LOW BATTERY CHECK IS DISABLED DURING POST
; ******************************************************************************
LOW_BALCHK PROC NEAR
F6 06 0012 R 01 TEST POSLSTATUS, POSLACTIVE ; IS POST CURRENTLY ACTIVE?
J FNZ LOWBEND YES, JUMP TO END
74 03 JZ $+5 IF NOT NOT ZERO JUMP AROUND JUMP
E9 0746 R JMP LOWBEND ELSE TAKE A LONG JUMP
E4 7F IN AL,PWR_STAT GET POWER INTERFACE
A8 80
TEST AL,LOW_BAT LOW BATTERY SIGNAL ON?
74 lC JZ LO NO LOW BATTERY SIGNAL - JUMP TO END
A8 40
TEST AL, EXLPWR I S EXTERNAL POWER SUPPLI ED?
75 18
JNZ LO YES EXTERNAL POWER - JUMP TO END
B4 17 MOV AH,RTCSYS_PROFI
E8 0747
CALL GELRTCNMI GET SYSTEM PROFILE
ROM BIOS 2-47