[Arm-netbook] [EOMA68-A20] SATA testing

joem joem at martindale-electric.co.uk
Wed Sep 4 20:14:55 BST 2013

um... anyone got any ideas as to why the voltage levels on Tx+ and Tx-
are 0.5V?  is that normal?

Yes its a differential interface that works on current instead of using voltage signaling.

If you want to see the signals, you could cut the track, put a serial 0.1R resistor
attach the scope probes across the resistor, and turn up the scope sensitivity.
You might see the packets flying past but probably not the signal itself as that
is running into GHz range. Higher values of resistor may work, but it all depends...

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