3-24
Computer Group Literature Center Web Site
Falcon ECC Memory Controller Chipset
3
Figure 3-5. Data Path for Writes to the Falcon Internal CSRs
External register data that is written on the upper data bus goes through the
upper Falcon, while data that is written on the lower data bus goes through
the lower Falcon. Unlike the internal register set, there is no automatic
copying of upper data to lower data for the external register set.
CSR read accesses can have a size of 1, 2, 4, or 8 bytes with any alignment.
CSR write accesses are restricted to a size of 1 or 4 bytes and they must be
aligned. Some Tester registers are limited to 4-byte only accesses.
, and
show the memory map for the
different kinds of access.
Upper FALCON
1904 9609
Up
p
e
r
Da
ta
Bu
s
Lo
w
er
Da
ta
Bu
s
CSR
MPC60
x
Master
Lower FALCON
CSR