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LS009.0
1997.01.16
RTL8029AS Preliminary
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6. FUNCTION DESCRIPTION
6.1. RTL8029AS Configuration Process
The RTL8029AS controller supports PCI configuration operation. In PCI system, the initial
process is completed by the system BIOS software. The system BIOS has to find where the system
resources are available, such as I/O base address, BROM memory base address, and interrupt
request line, and assigns the resources to the required devices. At the same time the RTL8029AS
controller performs a series of EEPROM read operation after power-up to set Ethernet ID, media
type, operation mode¡K, etc. The RTL8029AS's resource configuration information is stored in the
PCI configuration space as well as CONFIG registers in Group1 Page3. The CONFIG registers
power-up default values always come from the contents of 9346 and the values can be modified by
software. The update configuration is only valid temporarily and will be lost after an auto-load
command, an active RSTB, or PC power off. Permanent changes of configuration must be done by
changing the contents of 9346. Note that the BROM size can not be modified temporarily.