User guide

8.1 Ethernet Controller
The physical connection to the network is the Ethernet twisted-pair connector
located on the front panel of the module.
The Ethernet controller is based on the DECchip 21040-AA. This chip is a PCI-
based Ethernet solution that keeps processor intervention in LAN control to a
minimum. The DECchip 21040-AA behaves as a bus slave when communicating
with the PCI bus for access to configuration registers and control/status registers
(CSRs), and behaves as a bus master when communicating with memory.
Refer to the DECchip 21040-AA specification for details of programming and use.
8.1.1 PCI Configuration Registers
CPU Address: 0x1E0010000 - 0x1E0011FE0
PCI Address: 0x00001000 - 0x000010FF
The Ethernet controller responds to PCI configuration reads and writes to
its configuration registers (see Figure 8–2). For full bit definitions of these
registers, refer to the DECchip 21040-AA specification. Figure 8–2 shows the PCI
configuration space addresses of each register.
PCI bus 8–3