Motorola MCF5282, MCF5281 user manual Initialization Code, Precharge Sequence, Refresh Sequence

Models: MCF5282 MCF5281

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SDRAM Example

15.3.6 Initialization Code

The following assembly code initializes the SDRAM example.

Power-Up Sequence:

move.w #0x0026, d0//Initialize DCR move.w d0, DCR

move.l #0xFF880300, d0 //Initialize DACR0 move.l d0, DACR0

move.l #0x00740075, d0//Initialize DMR0 move.l d0, DMR0

Precharge Sequence:

move.l #0xFF880308, d0//Set DACR0[IP] move.l d0, DACR0

move.l #0xBEADDEED, d0//Write and value to memory location to init. precharge move.l d0, 0xFF880000

Refresh Sequence:

move.l #0xFF888300, d0//Enable refresh bit in DACR0 move.l d0, DACR0

Mode Register Initialization Sequence:

move.l #0x00600075, d0//Mask bit 19 of address move.l d0, DMR0

move.l #0xFF888340, d0//Enable DACR0[IMRS]; DACR0[RE] remains set move.l d0, DACR0

move.l #0x00000000, d0//Access SDRAM address to initialize mode register move.l d0, 0xFF800800

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MCF5282 User’s Manual

MOTOROLA

Page 338
Image 338
Motorola MCF5282, MCF5281 Initialization Code, Precharge Sequence, Refresh Sequence, Mode Register Initialization Sequence