Quote from: tolip_wen on July 18, 2014, 01:46:12 AM

My master plan has been thwarted once again

An AVR Dragon JTAG programmer can program Altera parts.
Programming a part is less complicated than debugging a running part in circuit.

It is _NOT_ recognised by the Altera software that I was going to use to try and snoop.

I threw $17.00 to the wind,
I ordered a clone of the Altera cable.
In ~20 days I'll know if that was wise or not.

The real deal 'cable' is $300 USD. What I want to try may need the real deal.

The whole snooping the FPGA is highly dependent on if they set it up that way.
I gambled $17 that early FW has access for KnC debugging.

Other clock related data.
The oscillator on the ASIC PCB that(I think) the ASIC uses as input reference for it's PLL is 25MHz.
The 28nm has 4 oscillators @ 25 or 250MHz.
I cross-referenced to 250 back when, but now have doubts seeing the 25MHz part on the 20nm PCB.

For the very bold, can try a slightly different osc.
Ideally a freq synthesizer instead of osc. to explore.
One might expect terrible results down that rabbit hole.
If it is the input clock for the ASIC, it's part of a tuned system on the ASIC.

Additionally,
I think the r/c components for the on die PLL are on the bottom of ASIC PCB.
If you examine bottom of PCB closely can see 2 very tiny parts(per die) that do not fit pattern of filter caps.
Again someone very bold can try the 'pencil trick' on the PLL resistors, if that is what they are.
Will need a microscope, VERY SHARP PENCIL, and very steady hand.
(assumes can tell which is cap and which is resistor)

The 'pencil trick' is just using graphite from a pencil to lower resistance on a SMD resistor.
You literally draw across top of resistor with pencil.
Lowering resistance of an r/c circuit speeds it up at a cost of more current.
Slight changes can be too much, it depends on design.
DIfferent hardness pencil can have different result.
It is often easily reversable with spit and finger.

Stalled clocks can be a bad thing!
I DO NOT ADVOCATE changing parts on the PCB!!!
Food for thought though.

YMMV

EDIT:
temporarily unthwarted, got a gizmo that kinda works on the Altera JTAG.
(but not with the Altera Quartus IDE yet)
Must forge some 'USB identification papers' for the thing I think.
Using openocd at the moment. (built in pun in the name!)
Also discovered that KnC made it trivial to do JTAG interfaces WITH the BBB.
('might only' require a cable from one end of PCB to other)

Thx KnCMiner!

The bar is kinda high for my skillset but I blunder on!

Prolly another instance of,
'tolip opens mouth, changes feet'

Keep up the good work Tolip