MVME5100 Single Board Computer Programmer's Reference Guide

Scrub Address Register
Programming Model
Note that when this register is all 0’s, the scrub prescale
counter does not increment, disabling any scrubs from
occurring. Since SCRUB_FREQUENCY is cleared to
0’s at power-up reset, scrubbing is disabled until software
programs a non-zero value into it.
0
0
R
RR
R
RR
X
XX
X
Address
Bit
$FEF80048
Name SCRUB ADDRESS
Operation READ/WRITE
Reset 0 P
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
0
0
SCRUB ADDRESS These bits form the address counter used by the scrubber
for all blocks of SDRAM. The scrub address counter
increments by one each time a scrub to one location
completes to all of the blocks of SDRAM. When it
reaches all 1s, it rolls back over to all 0s and continues
counting. The SCRUB_ADDRESS counter is readable
and writable for test purposes.
Note that for each block, the most significant bits of
SCRUB ADDRESS COUNTER are meaningful only
when their SDRAM devices are large enough to require
them.
http://www.motorola.com/computer/literature 3-53
30
31
0
0
X
X
3