NXP Semiconductors /LPC43xx /EMC /DYNAMICCONTROL

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Interpret as DYNAMICCONTROL

31 2827 2423 2019 1615 1211 87 43 0 0 0 0 0 0 0 0 00 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 (DISABLED)CE 0 (STOP)CS 0 (NORMAL_MODE)SR 0RESERVED 0 (ENABLED)MMC 0RESERVED 0 (NORMAL)I0RESERVED0RESERVED

SR=NORMAL_MODE, CS=STOP, MMC=ENABLED, I=NORMAL, CE=DISABLED

Description

Controls dynamic memory operation.

Fields

CE

Dynamic memory clock enable.

0 (DISABLED): Disabled. Clock enable of idle devices are deasserted to save power (POR reset value).

1 (ENABLED): Enabled. All clock enables are driven HIGH continuously.[1]

CS

Dynamic memory clock control. When clock control is LOW the output clock CLKOUT is stopped when there are no SDRAM transactions. The clock is also stopped during self-refresh mode.

0 (STOP): Stop. CLKOUT stops when all SDRAMs are idle and during self-refresh mode.

1 (RUN): Run. CLKOUT runs continuously (POR reset value).

SR

Self-refresh request, EMC SREFREQ. By writing 1 to this bit self-refresh can be entered under software control. Writing 0 to this bit returns the EMC to normal mode. The self-refresh acknowledge bit in the Status register must be polled to discover the current operating mode of the EMC.[2]

0 (NORMAL_MODE): Normal mode.

1 (SELF_REFRESH): Self-refresh. Enter self-refresh mode (POR reset value).

RESERVED

Reserved, user software should not write ones to reserved bits. The value read from a reserved bit is not defined.

MMC

Memory clock control.

0 (ENABLED): Enabled. CLKOUT enabled (POR reset value).

1 (DISABLED): Disabled. CLKOUT disabled.[3]

RESERVED

Reserved, user software should not write ones to reserved bits. The value read from a reserved bit is not defined.

I

SDRAM initialization.

0 (NORMAL): Normal. Issue SDRAM NORMAL operation command (POR reset value).

1 (MODE): Mode. Issue SDRAM MODE command.

2 (PALL): PALL. Issue SDRAM PALL (precharge all) command.

3 (NOP): NOP. Issue SDRAM NOP (no operation) command)

RESERVED

Reserved, user software should not write ones to reserved bits. The value read from a reserved bit is not defined.

RESERVED

Reserved, user software should not write ones to reserved bits. The value read from a reserved bit is not defined.

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