IBM 560 - Manual (Page 84)

System Configuration Service
Get Display Device State
Input Field
Major Function Number - 1 h
Minor Function Number -
h
Parameter 1 - Reserved
Parameter 2 - Request Type
= h : Current hardware
= 1h : CMOS (effective after reboot)
Parameter 3 - Reserved
Parameter 4 - Reserved
Parameter 5 - Reserved
A-20 ThinkPad 560/560E SMAPI BIOS