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Uthernet II Update – Part 2

Tuesday, May 12th, 2015

In my last update I said if all is well … Well all isn’t well.

The new boards had a flaw in them which I had introduced when trying to sub out one part for another. Once I figured that out, I proceeded to test a modified board and when doing extended tests I started seeing more timing issues. At this point the only model with full stability is my Enhanced IIe.

In an attempt to diagnose the issue, I have found it very difficult to take accurate measurements given the full SMT nature of the board. So I have ordered some new PCB’s with proper test points on them still using all the same components I would plan to use in production.

I will post another update once the new boards are in hand.

Update: Boards are back, stencil arrived today  … parts have also arrived.

Update: Test build build to start soon

 

Rev_V

 

Beta run

Friday, March 7th, 2014

The next revision of the PCB boards are on their way to me now. Parts to be ordered soon. Should have cards ready for the beta testers hopefully the end of next week. Wanted to give a shout out to David Finnigan of http://www.macgui.com/  for the Uthernet II logo gracing our home page.

Next Rev

Sunday, February 16th, 2014

SketchUp rendered rev2 board

 

Update #2

Sunday, February 16th, 2014

Hi I have a working board now but I realized I will need to spin another PCB before sending out a broader beta testing run.

The current PCB needs an inverter due to the way I hooked the LVCC4245 to the apple II bus. Once I added that I also found the LVCC4245 had some timing issues in the IIgs.

Replacing the LVCC4245 with a standard 74LS245D seems to work okay so far.

My first real world test other then web browsing was to use Contiki to participate in the IRC server on a2central.com the other night.

Progression

Sunday, February 16th, 2014

I thought perhaps some folks might like to see my hardware progression from Uthernet I to Uthernet II (after the decision was made to finalize on W5100 vs the other contenders).

So from left to right we have (1) the original Uthernet, then we have (2) a custom bridge adapter that let me use the WIZ811MJ module with the original Uthernet base board, then we have (3) PCB version of that adapter (while this works fine there are clearance issues in adjacent slots that make this too risky for a production solution imho) so I shelved that idea and moved on to (4) the AIO (All in One) card.