Ready for data transfer
Apply power
and start clock
NOP
NOP
NOP
NOP
NOP
Precharge all banks
NOP
NOP
Auto-refresh
NOP
NOP
NOP
Set SDRAM mode register
MEMSTMG1R.
INITREF
MEMSTMG0R.
TRCAR
MEMSTMG0R.
TRP
MEMSTMG1R.
TINIT
Figure 9-2 SDRAM power-on command sequence
SDRAM mode
initialization
The Memory Controller automatically sets the SDRAM devices' mode registers
during the power-up initialization.
If the SDRAM mode registers shall be rewritten during normal operation, set
MEMSCTRL.SDRMODE = 1.
After the Memory Controller finishes the SDRAM devices' mode register setting,
it clears MEMSCTRL.SDRMODE to 0.
Following parameters are written to the SDRAM devices' mode register:
Chapter 9
External Memory Interface Controller
296
Preliminary User's Manual S19203EE1V3UM00
Summary of Contents for uPD72256
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