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Using the DDR2 Memory Controller
Table 15. SDTIM2 Configuration
  | DDR2 SDRAM Data | 
  | 
  | 
  | 
  | 
Register Field | Sheet Parameter | 
  | Data Sheet  | Formula (Register  | Field  | 
Name | Name  | Description | Value  | Field Must Be ³)  | Value  | 
T_ODT  | tAOND  | tAOND specifies the ODT  | 2 (tCK cycles)  | CAS latency - tAOND - 1  | 1  | 
  | 
  | 
  | 
  | 
  | |
T_SXNR  | tSXNR  | Exit self refresh to a   | 137.5 nS  | (tSXNR ´ fDDR2_CLK) - 1  | 36  | 
  | 
  | command  | 
  | 
  | 
  | 
T_SXRD  | tSXRD  | Exit self refresh to a read  | 200 (tCK cycles)  | (tSXRD) - 1  | 199  | 
  | 
  | command  | 
  | 
  | 
  | 
T_RTP  | tRTP  | Read to precharge command  | 7.5 nS  | (tRTP ´ fDDR2_CLK) - 1  | 1  | 
  | 
  | delay  | 
  | 
  | 
  | 
T_CKE  | tCKE  | CKE minimum pulse width  | 3 (tCK cycles)  | (tCKE) - 1  | 2  | 
3.2.4Configuring the DDR2 Memory Controller Control Register (DMCCTL)
The DDR2 memory controller control register (DMCCTL) contains a read latency (RL) field that helps the DDR2 memory controller determine when to sample read data. The RL field should be programmed to a value equal to CAS latency plus 1. For example, if a CAS latency of 4 is used, then RL should be programmed to 5.
Table 16. DMCCTL Configuration
  | 
  | Register  | 
Register Field Name | Description | Value  | 
IFRESET  | Programmed to be out of reset.  | 0  | 
RL  | Read latency is equal to CAS latency plus 1.  | 5  | 
SPRUF85   | DSP DDR2 Memory Controller  | 35  | 
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