Specifications

EISA and ISA Bus Support
14.7 EISA Bus Support on DEC 2000
Note the driver is responsible for mapping the PA of the EISA board mem buffer
(=2.0000.0000 + (start_addr ^ 7)). Currently there are only 3 boards supported
which request memory buffers: DE422, DEFEA, and VGA card. However,
depending on how many of each of these cards are in the system, the available
memory resources can be exhausted. The VGA card is assigned addresses A0000-
C7FFF(3 chunks). The NI and FDDI cards compete for the same memory buffer
addresses, E0000/D0000. The NI card requires a 64K buffer, and asks for a
starting address of either E0000, or D0000. The FDDI card requires either a 32K
or 64K buffer, and asks for a starting address of either C8000, or E0000 then
D0000. So, we can not have 2 NI and 2 FDDI cards in the system at one time.
The resources limit the configuration to 1 NI & 2 FDDI or 1 FDDI & 2 NI. See
the later section on resource assignment for all the details of available resources.
14.7.6.3.3 CRB$L_NODE The CRB$L_NODE field contains information critical
to the success of these routines. If the driver is manually connected, the command
must include the "/NODE=%xyyyyzzzz" qualifier, where yyyy is the IRQ assigned,
and zzzz is the slot number the board is plugged into. For instance, if the console
assigns the board IRQ 5, and it is plugged into slot 6, the CONNECT command
would include /NODE=%x00050006. If the driver is autoconfigured, then this
field is filled in by the driver loading code.
14.7.7 DEC 2000 I/O Space Map
The Bus Support Code is responsible for creating a map of the I/O space. This is
done during bus probe time, as mentioned earlier. The ADP map created for DEC
2000 is shown in Figure 14–5.
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