131
DRAM control register (DCR) is set to 1 to use the address multiplex function, bits A23–A0 are
multiplexed and output from pins A15–A0, so a maximum 16-Mbyte space can be used. When
DRAM space is accessed, the
CS1
signal is not valid and the pin function controller should be set
for access with
CAS
(
CASH
and
CASL
) and
RAS
signals.
H'9000000
H'93FFFFF
H'9400000
H'97FFFFF
H'9800000
H'9BFFFFF
H'9C00000
H'9FFFFFF
H'1000000
H'1400000
H'1800000
H'1C00000
H'13FFFFF
H'17FFFFF
H'1BFFFFF
H'1FFFFFF
Shadow
Shadow
Shadow
External
memory
space
(4 Mbytes)
A27 = 0:
8-bit space
• Valid
address
A21–A0
(A23 and
A22 not
output)
•
CS1
valid
DRAME = 0 or DRAME = 1, MXE = 0
Logical address space
H'9000000
H'9FFFFFF
H'1000000
H'1FFFFFF
DRAM
space
(maximum
16 Mbytes)
DRAME = 1
Logical address space
Actual space
A27 = 1:
16-bit space
A27 = 0:
8-bit space
A27 = 1:
16-bit space
• Multiplexed
(MXE = 1):
16-bit space
• Not multi-
plexed
(MXE = 0):
4-Mbyte
space
•
CS1
not
valid (
CAS
,
RAS
output)
Actual space
Shadow
Shadow
Figure 8.6 Memory Map of Area 1
Areas 2–4: Areas 2–4 are areas with address bits A26–A24 set to 010, 011, and 100, respectively,
and address ranges of H'2000000–H'2FFFFFF and H'A000000–H'AFFFFFF (area 2), H'3000000–
H'3FFFFFF and H'B000000–H'BFFFFFF (area 3), and H'4000000–H'4FFFFFF and H'C000000–
H'CFFFFFF (area 4). Figure 8.7 shows a memory map of area 2, which is representative of areas
2–4.
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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