Analog Devices ADSP-21535 E-KIT LITE Manual Do Utilizador

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3.4  Using the SDRAM Interface 
In order to use the 4M x 32 bits (16 MB) of SDRAM memory, the three SDRAM 
control registers must be initialized.  The following table shows the standard 
configuration for these registers when using the EZ-KIT Lite in the default 
configuration.  These numbers were derived using the M48LC4M16ATG-75 with 
a system clock frequency of 120 MHz.   
Table 3-2: SDRAM Default Settings 
Register 
Value 
Function 
EBIU_SDRRC 
0x0000074A  RDIV = 1866 clock cycles 
EBIU_SDBCTL  0x00000001 
Bank 0 enabled 
Bank 0 size = 16 MB 
Bank 0 column address width = 8 bits 
EBIU_SDGCTL  0x0091998F  32 bit data path 
External buffering timing disabled 
t
WR
 = 2 SCLK cycles 
t
RCD
 = 3 SCLK cycles 
t
RP
 = 3 SCLK cycles 
t
RAS
 = 6 SCLK cycles 
pre-fetch disabled 
CAS latency = 3 SCLK cycles 
SCLK1 disabled 
 
If you are in an EZ-KIT Lite session (that is, not using an emulator), the SDRAM 
registers are configured automatically through the debugger.  The debugger uses 
the values in 
whenever bank 0 is accessed through the debugger (such 
as viewing memory windows or loading a program).  Clearing the appropriate 
checkbox on the Target Options dialog box, which is accessible through the 
Settings pull-down menu, disables this feature and allows manual configuration.  
An example program is included in the EZ-KIT installation directory, which 
demonstrates how to setup the SDRAM interface.   
3.5  Using Flash Memory 
The DSM2150 Flash/PLD chip provides a total of 272K x 16 bits of external flash 
memory, arranged into two independent flash arrays (boot and main).  The chip 
also has a series of configuration registers to control I/O and PLD.  This chip is 
initially configured with the memory sectors mapped to the DSP as shown below 
in 
 
 
ADSP-21535 EZ-KIT Lite Evaluation System Manual 
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