Read Status Register, 0xF6
GATEA20
BIT 0
GATEA20 is an internal signal from the
When set, indicates that data in the Read
EEPROM data register is valid. This bit is
cleared when EEPROM Data is read until the
next byte is valid. Reading the Read EEPROM
data register when bit 0 is clear will have no
detrimental effects; the data will simply be
invalid.
keyboard
controller
(Port
21).
The
FDC37C93xFR may be configured to drive this
signal onto GP25 by programming its GPI/O
Configuration Register. See the 8042 Keyboard
Controller section for more information.
133