AMD
P R E L I M I N A R Y
ISAPlugandPlayRegisterSet —TheAm79C930de-
vice fully supports the ISA Plug and Play specification,
revision 1.0a.
ADDRESS Auto-configuration Port, WRITE_DATA
Auto-configuration Port, and READ_DATA Auto-con-
figuration Port are all supported and are mapped into
ISA I/O space as follows:
The Am79C930 device supports the Plug and Play
Auto-configuration scheme. The Plug and Play
Am79C930 Device ISA Plug And Play Mode Supported Auto-Configuration Ports
Port Name
ISA (IEEE P996) I/O Address
Access
ADDRESS
WRITE_DATA
READ_DATA
0279h
0A79h
Write only
Write only
Read only
0203h – 03FFh (relocatable)
The location of the READ_DATA Auto-configuration
port is only fixed within the range 0203h–03FFh. The
exactlocationisdeterminedbyawritetotheappropriate
Plug and Play Auto-configuration port (Set
READ_DATA Auto-configuration port).
All Plug and Play ports are 8 bits in width.
To fully support the Plug and Play mechanism, the fol-
lowing additional register locations are defined within
the Am79C930 device. Except for the Resource Data
register, these registers are physically located within the
BIU and are accessed indirectly, through setting the
Plug and Play Port Address in the Plug and Play
ADDRESS port (location I/O 0279h) and then by ac-
cessing either the WRITE_DATA port or the
READ_DATA port. The 80188 embedded core does not
have access to the registers in the following table.
The WRITE_DATA port and the READ_DATA port are
not active until the Initiation Key has been sent to the
Am79C930 device through the ADDRESS port. This be-
havior conforms to the requirements of the Plug and
Play specification.
The Am79C930 device implements the four Plug and
Play configuration states: “Wait for Key,” “Sleep,”
Isolation,” and “Config.”
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Am79C930
AMD [ AMD ]
