GeneralPCBmedo/ESP8266

  

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 From:  koswix   8 Apr 2016 18:36 
 To:  CHYRON (DSMITHHFX)      81 of 111 
41688.81 In reply to 41688.75 
I'm working on a system that has to sample an analogue feed at about 50 kHz. I'm using an fpga to do it which supposedly is capable of sampling at 40 MHz, but I'm having a bitch of a time getting the timing right (as in recording the time of the sample, needs to be consistent). I hate it. Wish I could sample once a minute instead :((

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If Feds call you and say something bad on me, it may prove what I said are truth, they are afraid of it.
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 From:  Harry (HARRYN)   13 Apr 2016 19:32 
 To:  koswix      82 of 111 
41688.82 In reply to 41688.81 
50 KHz data rate - that is impressive.   Sometimes portions of the code are running much faster than others and you have to add "wait for data to be ready" code.

I have not written code in a long time, but I am working with an embedded code writer on a project and he runs into weird stuff like that all of the time.

I assume that you are using real time coding to pull that off?

edit

The company that I work for has struggled to use an FPGA sampling for analog sampling even at 10 ms sample rates and feed it into a controller error free.  There was a lot of noise in their incoming analog signal, more than they expected. 
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 From:  Harry (HARRYN)   13 Apr 2016 19:44 
 To:  ALL 83 of 111 
41688.83 
The only boards that I have built were for power LED + LED driver on one board.  For prototypes, I use Iconic PCB in Australia.  I know it sounds crazy, but they do a great job by cnc machining the boards and traces.

The main advantage for me was that I needed 2 oz copper traces (single layer) and a really healthy heat spreader + ground plane. 

They bonded together a 1.5mm copper sheet + thin FR4 + 2 oz copper stack for the project.  

- The 1.5mm copper was the ground plane and a great heat spreader.  Access to it was by machining openings down to it from the top, and filling in the opening with solder paste.  This was especially useful for the control chip heat spreader connection on the back of the package.  I also was able to use it for the LED heat spreading.

- FR4 layer - normal function

- 2 oz copper was for all non ground traces

- I used 0 ohm resistors to "jump" over traces as needed, rather than add another board layer.

- Typical part size was 1206, mostly because I have poor dexterity, but also it was handy to have larger parts for heat dissipation.

With this setup, I was able to duplicate an applications note circuit done in 4 layers with just the ground plane and 2 oz copper layer. 

I don't have the knowledge to design the circuit, so I hired a local EE to do the drawings.

The Iconics people are great, really a family business.


 
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 From:  koswix   13 Apr 2016 20:40 
 To:  Harry (HARRYN)      84 of 111 
41688.84 In reply to 41688.82 
Decided it wasn't possible in the end, at least not with my skill set and this hardware. I don't have the background or knowledge to pull it off at the level of accuracy asked for - 2 analogue channels being sampled, but the hardware muxes all analogue inputs through the same ADC so they physically cannot be read at the same time (which is what I was asked to do), even timing the sampling perfectly they samples end up being [sample time] + [switching input time] apart.

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If Feds call you and say something bad on me, it may prove what I said are truth, they are afraid of it.
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 From:  ANT_THOMAS    22 Apr 2016 10:00 
 To:  ALL 85 of 111 
41688.85 
Now testing a recovered 18650 cell with a couple of solar panels to charge.

This one should hopefully last longer because the solar panels no longer have a voltage drop with a diode.

Once the lithium charging boards with extra protection arrive (they're taking ages) I'll make a board up with all the bits properly soldered.

I suppose a board like this could be used as a reasonable battery backup type system for plugged in sensors. Saying that, if the power goes it will probably take out the server, wifi etc so it would be a little pointless.
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 From:  ANT_THOMAS    30 Apr 2016 23:15 
 To:  ANT_THOMAS       86 of 111 
41688.86 In reply to 41688.85 
This setup is currently at 9 days on solar+battery.

ESP recorded voltage hasn't dropped below the maximum it can read - 4.09V. Today I noticed that the charging module was showing "fully charged" so it looks like the two panels are providing enough power during the day to top up the battery to full. Might actually last forever if I want it to.
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 From:  Chris (CHRISSS)   4 May 2016 22:31 
 To:  ANT_THOMAS       87 of 111 
41688.87 In reply to 41688.86 
Nice one. Be good if it will keep going without needing to charge/replace batteries :) How much sunlight are they getting?
Me
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 From:  ANT_THOMAS    6 May 2016 09:40 
 To:  Chris (CHRISSS)      88 of 111 
41688.88 In reply to 41688.87 
I have two panels (6V - 0.6W and 1.1W). Attached to a south facing window, so getting as much as possible up north.

I could do with removing one of the panels to see if I can continue with just one.

(now unplugged the smaller one)
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 From:  ANT_THOMAS    6 May 2016 14:51 
 To:  ANT_THOMAS       89 of 111 
41688.89 In reply to 41688.88 
Small panel unplugged and the battery charger showed fully charged a moment a go.
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 From:  ANT_THOMAS    9 May 2016 11:58 
 To:  ANT_THOMAS       90 of 111 
41688.90 In reply to 41688.88 
Full charging with just the large panel, but there's been a lot of sun today so it's probably not a surprise. Time to try just running on the small panel.
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 From:  ANT_THOMAS    13 May 2016 09:04 
 To:  ANT_THOMAS       91 of 111 
41688.91 In reply to 41688.90 
Small panel looks like it isn't sufficient to keep the battery topped up. It has dropped below the 4.09V max voltage and over the last two nights has had a new low value so it's gradually getting lower over each night.
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 From:  graphitone   13 May 2016 13:03 
 To:  ANT_THOMAS       92 of 111 
41688.92 In reply to 41688.91 
How much sun have you had over the lat two days?


images?q=tbn:8nj2HfmLhyV7yM:b
Drawings n' that
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 From:  ANT_THOMAS    13 May 2016 13:04 
 To:  graphitone      93 of 111 
41688.93 In reply to 41688.92 
A lot in Lancashire.
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 From:  ANT_THOMAS    14 May 2016 15:40 
 To:  ALL 94 of 111 
41688.94 
RGB LED test
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 From:  CHYRON (DSMITHHFX)   14 May 2016 16:43 
 To:  ANT_THOMAS       95 of 111 
41688.95 In reply to 41688.94 
Disco!
Roland Skollani was sick of Pittsburgh. This city was the dead-end of his failed dreams and even dope didn’t help his choking fits no more. It had been a mistake to leave Hollywood and to follow Rita. Maybe it was a twist of fate, that there were only a few days left to leave his ex-wife’s house. Now he MUST act. Rita had a new lover and he didn’t mind, but why of all people did she choose this greedy, corrupt cop Lennon?
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 From:  ANT_THOMAS    17 May 2016 22:05 
 To:  ALL 96 of 111 
41688.96 
Made a notification RGB light
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 From:  ANT_THOMAS    22 May 2016 17:56 
 To:  ALL 97 of 111 
41688.97 
Made a standard doorbell a bit smarter



Connected up to the LED in the receiver unit which is now hooked up to an optoisolator which acts as a button/switch triggering the ESP8266 to do some stuff.

That stuff is currently tell my server to stick an entry in a database to record when there's a press.

And also telling my notification light to do something (currently flash).
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 From:  Matt   23 May 2016 13:12 
 To:  ANT_THOMAS       98 of 111 
41688.98 In reply to 41688.97 
The delay between the button press and the notification flashing is way too long.

In the time it takes to go off, any couriers ringing your bell will have already filled in a "sorry we missed you" card and moved on to their next stop!

doohicky
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 From:  ANT_THOMAS    23 May 2016 16:24 
 To:  Matt      99 of 111 
41688.99 In reply to 41688.98 
Ha, yeah definitely. Need to tweak it so it's quicker.
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 From:  graphitone   23 May 2016 20:16 
 To:  ANT_THOMAS       100 of 111 
41688.100 In reply to 41688.99 
Are you sure you've not just found a way of slowing light down?


images?q=tbn:8nj2HfmLhyV7yM:b
Drawings n' that
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