Bit
Bit name
Function
1
refresh all rows
3
PRCHALG
PRCHALG determines when a row is precharged
0
immediate precharge: row precharged at end of read/write operation
1
delayed precharge: row kept open after read/write operations
2
PWDM
PWDM control the power-down mode of the Memory Controller
0
leave power-down mode
1
force power-down mode
1
SREF
SREF controls the SDRAM self-refresh mode
0
leave SDRAM self-refresh mode
1
enter SDRAM self-refresh mode
0
INIT
By use of INIT the Memory Controller can be forced to initialize the SDRAM
0
initialization sequence is complete
1
force SDRAM initialization
This bit is set to "0" automatically once initialization sequence is complete.
Note:
After reset release INIT is set to "1", but is set to "0" after initialization is completed.
External Memory Interface Controller
Chapter 9
Preliminary User's Manual S19203EE1V3UM00
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Содержание uPD72257
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