IBM 770 manual Power-On Password, Other Passwords, System Board, Reference

Bit

6

If

set

to

1,

this

bit

indicates that

a

channel check has

occurred.

Bit

5

If

read,

this bit indicates the condition of the timer/counter

2

‘output’

signal.

Bit

4

If

read,

this

bit

toggles for each refresh request.

Bit

3

If

set

to

0,

this

bit

enables the channel check. This bit is

set to

1

during a

power-on reset.

Bit

2

If

set

to

0,

this

bit

enables

the

PCI

SERR#.

Bit

1

If

set

to

1,

this

bit

enables

the

speaker

data.

Bit

0

If

set

to

1,

this

bit

enables

the

timer

2

gate.

Power-On Password

RT/CMOS RAM	has	8	bytes reserved		for the power-on password
and the check character. The 8 bytes are initialized to								hex 00. The
microprocessor		can access		these	bytes only during POST. After
POST is completed, if a power-on					password	is installed,	the
password	bytes		are locked	and	cannot be	accessed by	any program.

During power-on password installation, the password (1 to 7 characters) is stored in the security space.

Installing the password is a function of the built-in system program Easy-Setup. The power-on password does not appear on the screen when it is installed, changed, or removed. After the power-on password has been installed, it can be changed or removed only during POST.

The computer also can have a keyboard password. For more

information, see the keyboard and auxiliary device controller section of theIBM Personal System/2 Hardware Interface Technical

Reference.

Other Passwords

In	addition to the power-on password, the computer provides two
more	passwords:

ŸThe hard-disk password (HDP) protects the data on your

removable hard disk drive from being accessed by unauthorized persons.

2-32 System Board