Programming Model
http://www.motorola.com/computer/literature 3-33
3
Revision ID/General Control Register
REVID The REVID bits are hard-wired to indicate the revision level of
the Falcon. The value for the first revision is $01, for the second is $02, for
the third it is $03.
aonly_en Normally, the Falcon pair responds to address-only cycles only
if they fall within the address range of one of its enabled map decoders.
When the aonly_en bit is set, the Falcon pair also responds to address-only
cycles that fall outside of the range of its enabled map decoders provided
they are not acknowledged by some other slave within 8 clock periods.
aonly_en is read-only and reflects the level that was on the CKD4 pin at
power-up reset.
isa_hole When it is set, isa_hole disables any of the DRAM or
ROM/Flash blocks from responding to PowerPC accesses in the range
from $000A0000 to $000BFFFF. This has the effect of creating a hole in
the DRAM memory map for accesses to ISA. When isa_hole is cleared,
there is no hole created in the memory map.
adis When adis is clear, fast page mode operation is used for back-to-back
pipelined accesses to the same page within DRAM. When it is set, RAS is
cycled between accesses. This bit should normally be cleared unless the
Falcon has a problem operating that way.
Address
$FEF80008
Bit
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
Name
REVID
0
0
0
0
0
0
aonly_en
isa_hole
0
0
0
adis
ram fref
ram spd0
ram spd1
chipu
Operation
READ ZERO READ ONLY
R
R
R
R
R
R
R
R/W
R
R
R
R/W
R/W
R/W
R/W
R
Reset
X $03
X
X
X
X
X
X
V P
0 PL
X
X
X
0 P
1 P
0 P
0 P
V P
To Next Page
Loading...
Need help?
General
