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Chapter 7
Bus and Memory Control (BCU, MEMC)
Preliminary User’s Manual U17566EE1V2UM00
(2)
16-bit data bus width
The page size or the number of continuously readable bits is 8 x 16 bit. To
provide 8 addresses, a 3-bit on-page address is required. Therefore, set
PRC.MA[6:3] = 0001
B
.
Note
For a 16-bit data bus, bit A0 of the output address is not used.
Figure 7-6
16-Mbit page ROM (1 M × 16 bits), page size 8 x 16 bit
(3)
32-bit data bus width
The page size or the number of continuously readable bits is 2 x 32 bit. To
provide 2 addresses, a 1-bit on-page address is required. Therefore, set
PRC.MA[6:3] = 0000
B
.
Note
For a 32-bit data bus, bits A0 and A1 of the output address are not used.
A4
A0
Internal address latch
(immediately preceding
address)
Output address
Page ROM address
Off-page address
MA6
0
MA5
0
MA4
0
MA3
1
PRC register setting
Comparison
A3
A5
A6
A7
...
...
A22
A4
A3
A5
A6
A7
A22
A2
A1
A2
A1
A3
A4
A6
A18
A0
On-page address
...
A5
A19
A19
A21
A20
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