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<DIV><FONT face=Arial size=2>Hi,</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>I am using spd_82801.c file to get the SPD values
of the my DDR SDRAM. I have checked the values and it seem to be
correct.</FONT></DIV>
<DIV><FONT face=Arial size=2>Now I want to program the DRAM registers. When I
was browsing the 440gx code, I could found that these SPD values are not used
directly to</FONT></DIV>
<DIV><FONT face=Arial size=2>get the DRAM register value. </FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>I could not understand the step used to
calculate the DRAM register values. In the specification I could see only the
description of DRAM register, not the </FONT></DIV>
<DIV><FONT face=Arial size=2>steps to calculate the value of DRAM register.
Where can I find those steps? How do you get to know for the 440gx ? Is it ok to
hardcode the values ?</FONT></DIV>
<DIV><FONT face=Arial size=2>I am going for this option because our system is a
embedded system, so the configuration will not change.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Also while browsing the 440gx code, I found
that most of the register are left with default values. Can any one
giving some idea about the set of registers which I need to
</FONT></DIV>
<DIV><FONT face=Arial size=2>program. I have attached the output of the SPD
program. But how to calculate the DRAM register values like DRB, DRT, DRC,FDHC
and etc., </FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>The Output of the SPD_82801.c file on my DDR
SDRAM:</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>[root@wipro2 scanspd]# ./spd_82801ba<BR>dev=1f,
fn=3<BR>IO_BASE=5000<BR>After reset status 0x40<BR><STRONG>SLOT
0<BR></STRONG>After reset status 0x40<BR><STRONG>Number of bytes used by module
manufacturer 0x80<BR></STRONG>After reset status 0x40<BR><STRONG>Memory Type
0x07 ---------------> DDR SDRAM<BR></STRONG>After reset status
0x40<BR><STRONG>Number of Row Address bits 0x0d<BR></STRONG>After reset status
0x40<BR><STRONG>Number of Column Address bits 0x0a<BR></STRONG>After reset
status 0x40<BR><STRONG>Number of Sides 0x01<BR></STRONG>After reset status
0x40<BR><STRONG>DIMM Configuratio type 0x00<BR></STRONG>After reset status
0x40<BR><STRONG>Refresh Rate 0x82-------------------------------> refresh
rate is 7.8 micro sec<BR></STRONG>After reset status 0x40<BR><STRONG>Number of
Banks 0xa0<BR></STRONG>After reset status 0x40<BR><STRONG>Module Bank Density
0x40<BR></STRONG>After reset status 0x40<BR><STRONG>SPD Revision Code
0x00<BR></STRONG>After reset status 0x40<BR><STRONG>CAS # Latency
0x0c
-----------------------> 2.5<BR></STRONG>After reset status
0x40<BR><STRONG>Min Row Precharge 0x50<BR></STRONG>After reset status
0x40<BR><STRONG>Min RAS to CAS Delay 0x50 ------------------------------> 20
ns<BR></STRONG>After reset status 0x40<BR><STRONG>Min RAS Pulse Width
0x2d<BR></STRONG>[root@wipro2 scanspd]#<BR></FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Thanks,</FONT></DIV>
<DIV><FONT face=Arial size=2>Siva</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
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