Specifications

Futurebus+ Bus Support
15.12 Futurebus+ on DEC 10000/7000
As a Futurebus+ master, the Flag can generate A32 and A64 address width
transactions, and D32 and D64 data width transactions.
As a Futurebus+ slave, the Flag accepts both A32 and A64 address width
transactions, and D32 and D64 data width transactions.
15.12.2 DEC 10000/7000 Futurebus+ Address Space
The DEC 10000/7000 system supports a 40 bit (1 TB) memory address space. The
Flag module maps Futurebus A32 space to DEC 10000/7000 memory space as
shown in Figure 15–10
Figure 15–10 Futurebus+ A32 Space
ZK−6735A−GE
CSR
space
Futurebus+ A32 Space DEC 10000/7000 System Memory
00 0000 0000
FF FFFF FFFF
0000 0000
EFFF FFFF
F000 0000
FFFF FFFF
00 EFFF FFFF
The Flag responds as a Futurebus+ slave to A32 transfers from 00000000
to EFFFFFFF in Futurebus+ 32 bit address space and passes the transfer
to DEC 10000/7000 system memory. DEC 10000/7000 system memory above
00EFFFFFFF is not accessible from the Futurebus+ using 32 bit addressing.
Since the Flag module consumes the entire A32 address region (except for CSR
space), Futurebus+ adapters which require A32 space (that is, which require A32
address space in addition to their CSR space) will not work on DEC 10000/7000.
The Flag module maps Futurebus+ 64 bit address space as shown in
Figure 15–11.
15–15