Difference between revisions of "Developer Manual"

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== RAM init ==
== RAM init ==

One of the most important tasks of coreboot is to initialize your system RAM.
See [[Developer Manual/RAM init]].
=== SDRAM ===
There are a number of steps you have to perform to properly initialize SDRAM. This depends on the chipset, as well as the DIMMs which are inserted into the mainboard (and their properties, such as CAS latencies, and so on).
Sample northbridge datasheets:
* http://support.intel.com/design/chipsets/810/
* http://support.intel.com/design/chipsets/datashts/290656.htm
* http://download.intel.com/design/chipsets/datashts/29065602.pdf
Sample SDRAM datasheets:
* http://www.micron.com/products/partdetail?part=MT48LC16M16A2BG-75
* http://download.micron.com/pdf/datasheets/dram/sdram/256MSDRAM.pdf
=== DDR ===
=== DDR2 ===
=== DDR3 ===
=== Resources ===
<!--* [ JEDEC SDRAM Standard] TODO -->
* [http://www.intel.com/design/chipsets/memory/spdsd12a.pdf Intel SPD Standard]
<!--* [ JEDEC SPD Standard] TODO -->
* [http://download.micron.com/pdf/datasheets/dram/sdram/512MbSDRAM.pdf Micron 512 MB SDRAM Datasheet] (PDF) -- contains some helpful explanations
<!--* [ JEDEC DDR Standard] (PDF) Explains the RAM initialization process TODO-->
* [http://www.jedec.org/download/search/4_01_02_04R13.PDF JEDEC DDR SPD Standard] (PDF)
* [http://www.simmtester.com/page/news/showpubnews.asp?num=101 Understanding DDR Serial Presence Detect (SPD) Table]
* [http://download.micron.com/pdf/datasheets/modules/ddr/DDA9C16_32_64x72AG.pdf Micron DDR400 Datasheet]
* [http://www.jedec.org/download/search/JESD79-2C.pdf JEDEC DDR2 Standard] (PDF)
* [http://www.jedec.org/download/search/4_01_02_04R13.PDF JEDEC DDR2 SPD Standard] (PDF)
* [http://www.simmtester.com/PAGE/news/showpubnews.asp?where=373939&num=139 DDR2 DIMM SPD Definition]
<!-- TODO: Add datasheet links (Micron ones are very good) -->
<!-- Need to find these
* [ JEDEC DDR3 Standard] (PDF)
* [ JEDEC DDR3 SPD Standard] (PDF)-->
* [http://www.simmtester.com/PAGE/news/showpubnews.asp?num=153 Understanding DDR3 Serial Presence Detect (SPD) Table]
Note: Micron lists SPD values for all the memory they produce. This really helps when trying to trouble shoot memory and SPD values.  [http://www.micron.com/support/part_info/spd Micron SPD Lookup]

== Southbridge ==
== Southbridge ==

Revision as of 13:29, 24 June 2009