IBM 6H0, Service Manual

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Message Hierarchy for Secondary I/O Drawer Operator Panel
The messages that are displayed in the operator panel on secondary I/O drawers are
arranged hierarchically, from highest priority to lowest priority. The message hierarchy is
as follows:
1. 8-character error code
This indicates a critical error; the drawer power will be shut down. Standby power is
still on, so the error message is still displayed in the operator panel. The I/O drawer
Attention LED will be on. The error code displays on the top line of the display
panel, left-justified. A FRU part number may also be displayed, right-justified, in the
second line of the display.
2. 8-character informational message
This is a noncritical message, so the drawer power will not be shut down. The
message should be investigated to see if service actions are indicated. A FRU part
number may also be displayed, right-justified, in the second line of the display.
When 8-character codes are displayed, they are in the form
10n1xxxx
, where
n
is
the drawer number.
3. 8-character checkpoint
There is one 8-character checkpoint that will be displayed, 10n100AA , where n is the
drawer number. This checkpoint indicates that the system power control network
firmware is being updated, and the checkpoint will be displayed for approximately
15 seconds. This is the only checkpoint that displays on a secondary I/O drawer
operator panel.
4. Drawer number
This will be in the form
U0.n
, where
n
is the drawer number. This message will
normally be displayed unless a higher-level message is required.
When ac power has been disconnected from the system, then reconnected, the I/O
drawer addresses on the secondary drawers will temporarily display in the format
*0n
, where
n
is the drawer number. After the system is powered on, and the boot
sequence has been initiated, the drawer numbers are restored to the
U0.n
format.
Chapter 1. Reference Information
29