606
A.2.40
Bus Control Register (BCR)
BSC
•
Start Address: H'5FFFFA0
•
Bus Width: 8/16/32
Register Overview:
Bit:
15
14
1312
11
10
9
8
Bit name:
DRAME
IOE
WARP
RDDTY
BAS
—
—
—
Initial value:
0
0
0
0
0
0
0
0
R/W:
R/W
R/W
R/W
R/W
R/W
—
—
—
Bit:
7
6
5
4
32
1
0
Bit name:
—
—
—
—
—
—
—
—
Initial value:
0
0
0
0
0
0
0
0
R/W:
—
—
—
—
—
—
—
—
Table A.41 BCR Bit Functions
Bit
Bit Name
Value
Description
15
DRAM enable (DRAME)
0
Area 1 is external memory space
(Initial value)
1
Area 1 is DRAM space
14
Multiplex I/O enable (IOE)
0
Area 6 is external memory space
(Initial value)
1
Area 6 is address/data multiplex I/O space
13Warp mode (WARP)
0
Normal mode: External access and internal
access not performed simultaneously
(Initial value)
1
Warp mode: External access and internal
access performed simultaneously
12
RD duty (RDDTY)
0
RD
signal high width duty ratio is 50%
(Initial value)
1
RD
signal high width duty ratio is 35%
11
Byte access select (BAS)
0
WRH
,
WRL
, and A0 signals valid
(Initial value)
1
WR
,
HBS
, and
LBS
and signals valid
Summary of Contents for HD6417032
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Page 525: ...490 CK RAS CAS TRp TRc TRcc tRASD1 tRASD2 tCASD3 tCASD2 TRr tCSR Figure 20 18 Self Refresh ...
Page 578: ...543 CK RAS CAS TRp TRc TRcc tRASD1 tRASD2 tCASD3 tCASD2 TRr tCSR Figure 20 62 Self Refresh ...
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