Programming Model
DRAM Controller 7-13
The REF value is the time of 1 refresh cycle.
Example 7-1. Calculating REF Field Values for Refresh Times
When CLK =0, 32 kHz (or 34.8kHz) is used for refresh control.
If REF =0, the refresh rate =2 ×32kHz.
If REF =1, the refresh rate =32 kHz.
If REF =(2 to 15), t he refresh rate= 32 kHz/ (REF +1).
When CLK =1, the system clock is used for refresh control.
The refresh rate= SYSCLK /(32 ×(REF+ 1)).
REF
Bits 4–0 Refresh Cycle—This value determines the refresh rate for
the DRAM controller. The refresh rate can be calculated
using the equation shown in Example7-1.
See description
Table 7-6. DRAM Memory Configuration Register Description (Continued)
Name Description Setting