65 PCIE-5565PIORC Reflective Memory Board
space.
This
gives
the
user
application
PIO
access
to
the
Reflective
Memory
locations
$00000000
up
to
$001FFFFF.
The
user
application
can
set
the
Local
Base
Address
(Remap)
register
pointing
to
any
valid
window
in
the
installed
memory.
For
example,
the
user
application
can
write
$00200000
to
the
Remap
register
to
access
the
second
2
MByte
PCI
PIO
window.
The
register
value
will
be
$00200001
since
bit
‐
0
is
hardwired
to
1.
This
gives
the
user
application
PIO
access
to
the
Reflective
Memory
locations
$00200000
up
to
$003FFFFF.
The
user
application
uses
the
same
PCIBAR3
window
ranging
from
$F7600000
up
to
$F77FFFFF.
NOTE
After writing a new value to the LAS1BA remap register, the user application should read the
LAS1BA remap register before accessing the new window. This ensures the new window mapping
has taken effect and subsequent memory accesses will be to the new memory window.
In
summary,
register
LAS1RR
is
the
range
register
corresponding
to
the
size
of
the
PCI
window
and
is
read
‐
only.
Register
LAS1BA
is
the
writeable
base
address
register.
It
is
used
to
remap
or
offset
the
PCI
PIO
window
to
access
other
sections
of
the
installed
memory.
The
RFM
‐
5565
firmware
prevents
the
user
from
entering
an
invalid
Remap
Value.
The
value
written
must
be
a
multiple
of
the
PCI
window
size.
For
example,
using
a
PCI
window
size
of
2
MByte
with
64
MByte
of
installed
memory
means
there
are
32
valid
base
address
settings
from
$00000000
to
$03E00000,
incrementing
by
$00200000
(all
other
bits
are
masked
off
when
written).
Also,
a
64
MByte
card
with
a
64
MByte
window
has
no
valid
base
address
settings
other
than
the
default
0.
Since
the
PCI
window
size
and
the
Remap
register
only
affect
PCI
PIO
accesses,
DMA
(Local
‐
to
‐
PCI
and
PCI
‐
to
‐
Local)
can
be
used
normally
to
transfer
up
to
$7FFFFF
bytes
with
another
location
on
the
PCI
bus
regardless
of
the
Remap
value.