Int 15/AX=2400h

AX = 2400h

Return:
CF clear if successful
AH = 00h
CF set on error
AH = status
01h keyboard controller is in secure mode
86h function not supported

Notes: Also supported by AMI PCI BIOS and Qualitas 386MAX v6.01+. IBM classifies this function as optional

BUG: AMI BIOS v1.00.03.AV0M never reports an error on failure to disable the A20 gate; it simply writes 0 to PORT 0092h

See Also: AX=2401h - AX=2402h - AX=2403h - PORT 0092h