I believe that "-x GB" simply means that there are different Trfc values
for each size module.
Trfc is stored in MTB units, though. So you need to:
1. Convert nCK to nanoseconds
2. Convert nanoseconds to MTB units
For example, if you have a 1Gb module that is running at 800MHz, then Trfc
will be 88 clock cycles. 1sec / 800MHz = 1.25ns per cycle, therefore 88
cycles = 110ns.
Then you need to convert the total time into MTB units. So if your timebase
(SPD bytes 10 and 11) is 0.125, Trfc is 110 / 0.125 = 880. (This matches
the calculation shown for bytes 24 and 25 in the SPD spec:
On Fri, Apr 1, 2016 at 5:30 PM, Zheng Bao <fishbaoz(a)hotmail.com> wrote:
7-7-7 9-9-9 11-11-11
nRFC-1 Gb 59 74
88 103 nCK
nRFC- 2 Gb 86 107 128
nRFC- 4 Gb 160 200 240
nRFC- 8 Gb 187 234 280
Above text is extracted from the spec of a DDR3 chip.
I am trying to decide the Trfc.
What does "-x Gb" mean? How do I know which row in the table I should use?
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