INT 15,43 - Read System Status (convertible only)

AH = 43h

on return

AL = STATUS:

¦7¦6¦5¦4¦3¦2¦1¦0¦ AL

¦ ¦ ¦ ¦ ¦ ¦ ¦ +---- LCD detached

¦ ¦ ¦ ¦ ¦ ¦ +----- reserved

¦ ¦ ¦ ¦ ¦ +------ RS232/parallel powered on

¦ ¦ ¦ ¦ +------- internal modem powered on

¦ ¦ ¦ +-------- power activated by alarm

¦ ¦ +--------- standby power lost

¦ +---------- external power in use

+----------- battery low