Hayes Microcomputer Products RCV56HCF - Manual (Page 62)

RCV56HCF PCI/CardBus Modem Designer’s Guide
ROCKWELL PROPRIETARY INFORMATION 1129 5-4
5.3 SERIAL EEPROM INTERFACE
The serial EEPROM interface is used to load PCI configuration parameters and CIS information (required for Card Bus
operation) after a reset occurs. The PCI configuration information to be loaded requires 10 bytes of data. The CIS
information requires 384 bytes of data. The minimum serial EEPROM size is 512 bytes (4096 bits). After the PCI reset signal
is negated, the configuration data is read from the serial EEPROM and stored in the PCI configuration registers as required,
then the CIS information is read from the serial EEPROM and stored in the internal RAM of the BIF. While the serial
EEPROM data is being read and is being loaded in the configuration registers and the CIS RAM, any PCI access that occurs
will receive a RETRY signal from the BIF device. After completion of the serial EEPROM reads, the BIF device will accept
PCI transactions.
The data stored in the serial EEPROM is in 16 bit word format. The configuration data to be read from the serial EEPROM is
shown in Table 5-5.
Table 5-5. EEPROM Configuration Data
EEPROM Address Copied to
0x0 Configuration Register Device ID
0x1 Configuration Register Vendor ID
0x2 Configuration Register Subsystem Device ID
0x3 Configuration Register Subsystem Vendor ID
0x4 (LSBs) Configuration Register Min Grant
0x4 (MSBs) Configuration Register Max Latency
Beyond 0x4 CIS RAM