Key Module Operation; Shift-Lock Mechanism; Basic Assurance Test (Bat) - IBM 6580 Product Support Manual

Flat
Spring
Fly Plate
~]~~3~-;
Compression Spring
Spring_;~!~~~~~~~~;;
Fly Plate
Normal
FullyP,BIS8d
Pad Card Capacitor Plate
Stem
Assembly
Key Module Operation
Shift Reset
Bail
Shift-Lock Restoring Mechanism
Key Module Operation,
KEYBOARD - Shift Lock Mechanism, BAT
-7-
BASIC ASSURANCE TEST (BAT)
A Power on Reset (POR) of the system will automatically
start the keyboard Basic Assurance Test (BAT) and perform
wrap tests on the keyboard adapter circuits of the system
card.
The keyboard BAT will verify the keyboard microproces·
sor, located on the keyboard logic card is operating cor·
rectly. The keyboard notifies the system processor of the
keyboard status by transmitting a specified sequence of
two bytes of data. Successful completion of the BAT is
necessary for the keyboard to proceed with normal sys·
tern operation.
A third byte containing the keyboard ID is also transmitted
to provide configuration information.
System Power·On· Reset
BAT Signal to Keyboard Microprocessor
BAT Self·test of Keyboard Microprocessor
BAT Completion Codes Transmitted
System Electronics Accepts Data Byte Codes
Keyboard ID Transmitted
Keyboard Operational