612
Table A.45 DCR Bit Functions
Bit
Bit Name
Value
Description
15
2-CAS system/2-WE
system (CW2)
0
2-CAS system:
CASH
,
CASL
, and
WRL
signals are
valid
(Initial value)
1
2-WE system:
CASL
,
WRH
, and
WRL
signals are
valid
14
RAS down (RASD)
0
RAS up mode: Returns
RAS
signal to high and waits
for next DRAM access
(Initial value)
1
RAS down mode: Leaves
RAS
signal low and waits
for next DRAM access
13Number of RAS pre-charge
0
1-cycle pre-charge cycle inserted
(Initial value)
cycles (TPC)
1
2-cycle pre-charge cycle inserted
12
Burst operation enable (BE)
0
Normal mode: Full access
(Initial value)
1
High-speed page mode: Burst operation
11
CAS duty (CDTY)
0
CAS
signal high width duty ratio is 50% (Initial value)
1
CAS
signal high width duty ratio is 35%
10
Multiplex enable (MXE)
0
Row address and column address not multiplexed
(Initial value)
1
Row address and column address multiplexed
9,8
Multiplex shift count 1,0
(MXC1, MXC0)
Row address shift
(MXE = 1)
Row address for comparison
during burst (MXE = 0 or 1)
0
0
8 bits (Initial value)
A27–A8
(Initial value)
0
1
9 bits
A27–A9
1
0
10 bits
A27–A10
1
1
Reserved
Reserved
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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