![](http://datasheet.mmic.net.cn/30000/MC68EN360FE33_datasheet_2368935/MC68EN360FE33_808.png)
Applications
9-88
MC68360 USER’S MANUAL
one refresh every 15.6
s.
RFEN should be set.
RCYC depends on the DRAM speed. At 25 MHz (an 80-ns DRAM SIMM), RCYC should
be 00.
PGS2–PGS0 should be set to 011 for the 1M
× 32 DRAM SIMM.
DPS should be set to 00 (32-bit DRAM port size).
WBT40 does not apply to this application.
WBTQ depends on timing; it should be set for 80-ns MCM32100 SIMMs.
DWQ should be set if page mode enabled (PGME = 1).
DW40 does not apply to this application.
EMWS is not used in synchronous mode. (SYNC = 1)
SYNC should be set for a synchronous operation of the memory controller.
OPAR does not apply to this application.
PBEE does not apply to this application.
TSS40 does not apply to this application.
NCS should normally be cleared.
GAMX should be cleared for an external master system.
The memory controller status register (MSTAT) is used for reporting write protect and parity
errors and does not require initialization.
The eight base registers (BRs), one for each memory bank, should be configured as follows:
The BA27–BA11 bits may be set as desired. Different memory arrays should not overlap.
BA31–BA28 should be cleared since the byte write lines are used with an external master
in the system.
For simplicity, FC3–FC0 can be cleared.
TRLXQ depends on timing of memory/peripheral.
BACK40 does not apply to this application.
CSNT40 does not apply to this application.
CSNTQ should normally be cleared.
PAREN should be cleared since parity is not used in this application.
WP should be set for EPROM and flash EPROM; otherwise, it should be cleared.
V should be set if the memory bank is used.
The eight option registers (ORs), one for each memory bank, should be configured as fol-
lows:
The TCYC bits should be set to determine the number of wait states required.
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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