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GIGABYTE 6VLE-VXL I2C data
-------------------------------------------------------------------------------
This is an example capture of I2C traffic on a DDR SDRAM's EEPROM chip, for
Serial Presence Detect (SPD) data. The 512MB DDR RAM module was inserted
in a GIGABYTE 6VLE-VXL mainboard. After the capture was started, the board
was powered-on, thus the captured data corresponds to the BIOS code which
reads the RAM module's EEPROM contents (in order to properly initialize
the RAM).
Additionally, it turned out that on the same I2C bus, there is an additional
I2C device, the ICS950908 "Programmable Timing Control Hub for P4" (a clock
generation chip). The capture also contains the I2C-based configuration of
that chip by the BIOS.
Details:
https://en.wikipedia.org/wiki/Serial_presence_detect
http://pdf1.alldatasheet.com/datasheet-pdf/view/90645/ICST/ICS950908.html
Logic analyzer setup
--------------------
The logic analyzer used was a Saleae Logic (at 2MHz):
Probe I2C pin
-------------------
1 (black) SCL
4 (orange) SDA
Data
----
The sigrok command line used was:
sigrok-cli -d 0:samplerate=2mhz --time 10s -o <filename>
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