Motorola MVME5100 Manual Do Utilizador

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Programming Model
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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.
Scrub Address Register
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.
Address
$FEF80048
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
0
0
0
SCRUB ADDRESS
0
0
0
Operation
R
R
R
READ/WRITE
R
R
R
Reset
X
X
X
0 P
X
X
X