Rev. 1.0, 09/01, page 180 of 904
6.7
Synchronous DRAM Interface
In the H8S/2378R Series, external address space areas 2 to 5 can be designated as continuous
synchronous DRAM space, and synchronous DRAM interfacing performed. The synchronous
DRAM interface allows synchronous DRAM to be directly connected to this LSI. A synchronous
DRAM space of up to 8 Mbytes can be set by means of bits RMTS2 to RMTS0 in DRAMCR.
Synchronous DRAM of CAS latency 1 to 4 can be connected.
Note: * The synchronous DRAM interface is not supported in the H8S/2378 series.
6.7.1
Setting Continuous Synchronous DRAM Space
Areas 2 to 5 are designated as continuous synchronous DRAM space by setting bits RMTS2 to
RMTS0 in DRAMCR. The relation between the settings of bits RMTS2 to RMTS0 and
synchronous DRAM space is shown in table 6.7. Possible synchronous DRAM interface settings
are and continuous area (areas 2 to 5).
Table 6.7
Relation between Settings of Bits RMTS2 to RMTS0 and Synchronous DRAM
Space
RMTS2
RMTS1
RMTS0
Area 5
Area 4
Area 3
Area 2
0
0
1
Normal space
Normal space
Normal space
DRAM space
1
0
Normal space
Normal space
DRAM space
DRAM space
1
DRAM space
DRAM space
DRAM space
DRAM space
1
0
Continuous synchronous DRAM space
*
0
1
Mode settings of synchronous DRAM
1
0
Reserved (setting prohibited)
1
Continuous DRAM space
With continuous synchronous DRAM space,
&6
5
,
&6
6
,
&6
7
pins are used as
5$6
,
&$6
,
:(
signal. The (
2(
) pin of the synchronous DRAM is used as the CKE signal, and the
&6
8
pin is
used as synchronous DRAM clock (SDRAM
φ
). The bus specifications for continuous
synchronous DRAM space conform to the settings for area 2. The pin wait and program wait for
the continuous synchronous DRAM are invalid.
Commands for the synchronous DRAM can be specified by combining
5$6
,
&$6
,
:(
, and
address-precharge-setting command (Prechrge-sel) output on the upper column addresses.
Commands that are supported by this LSI are NOP, auto-refresh (REF), self-refresh (SELF), all
bank precharge (PALL), row address strobe bank-active (ACTV), read (READ), write (WRIT),
and mode-register write (MRS). Commands for bank control cannot be used.
Содержание H8S/2376 F-ZTAT
Страница 24: ...Rev 1 0 09 01 page xxiv of xliv ...
Страница 38: ...Rev 1 0 09 01 page xxxviii of xliv ...
Страница 44: ...Rev 1 0 09 01 page xliv of xliv ...
Страница 60: ...Rev 1 0 09 01 page 16 of 904 ...
Страница 96: ...Rev 1 0 09 01 page 52 of 904 ...
Страница 116: ...Rev 1 0 09 01 page 72 of 904 ...
Страница 148: ...Rev 1 0 09 01 page 104 of 904 ...
Страница 284: ...Rev 1 0 09 01 page 240 of 904 ...
Страница 422: ...Rev 1 0 09 01 page 378 of 904 ...
Страница 634: ...Rev 1 0 09 01 page 590 of 904 ...
Страница 656: ...Rev 1 0 09 01 page 612 of 904 ...
Страница 668: ...Rev 1 0 09 01 page 624 of 904 ...
Страница 780: ...Rev 1 0 09 01 page 736 of 904 ...
Страница 796: ...Rev 1 0 09 01 page 752 of 904 ...
Страница 806: ...Rev 1 0 09 01 page 762 of 903 ...
Страница 808: ...Rev 1 0 09 01 page 764 of 904 ...
Страница 921: ...Rev 1 0 09 01 page 877 of 904 ø tBRQOD tBRQOD Figure 24 24 External Bus Request Output Timing ...
Страница 938: ...Rev 1 0 09 01 page 894 of 904 ...