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Paul “LeoNerd” Evans

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I'm currently trying to work out the best way to mount one of those little SSD1306 128x64 OLED modules (e.g. onto an aluminium front panel.

Getting it physically in place isn't too hard because it has screwholes, but I'm trying to find something nice to do with the actual opening hole. There don't seem to be plastic bezels available for this kind of display.

I don't like the idea of a "raw" cutout in the aluminium panel - that'll let in dust and generally look ugly. But so far coming up short on a better idea.

Anyone have any thoughts?
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No, #google+, I don't want to copy the entire text of a 100-line post to the clipboard; I want to press and highlight one sentence. Just like in any actually-sensible app.

Did you consider there may be a reason that basically nobody uses this??
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So that was a new experience for me. I've just written an email to my MP. Here's what I wrote:



I don't normally make a habit of writing to my MP, but then these aren't exactly normal times. So I'll start by saying I hope this comes across OK.

I'm sure you're aware that our constituency of Twickenham voted in favour of Remain. I was one of those voters. My reasons were many-fold. I see from your website you share many of my concerns.

In a personal capacity, I have many friends from all around Europe - I enjoy visiting them in their countries as much as receiving them as guests in our own.

On a professional note I'm a computer and electronics engineer, a self-employed contractor, and designer/constructor of various small-run products. I buy components and sell completed products online, and most of my trade happens with Europe.

As I'm sure you'll appreciate, in any market selling products there's rules to be followed. I'm thankful of the fact that the same rules generally apply to the UK and Europe; this means less hassle for me when designing things.

As we begin one of the most unsure weeks certainly I can recall in this country's history, I would be interested to hear how you are representing at Parliament the cause of the voters of Twickenham such as myself. I'm aware you can't give any hard guarantees - in the current situation I think anyone who claimed they could would be either foolish, lying, or both.

However, for me the most important points are:

 * The freedom of movement of Brits to Europe, and Europeans to Britain for both leisure and business purposes

 * The freedom of trading goods and services between Britain and Europe

 * The harmonisation of rules and regulations regarding those goods and services so traded

Any assurance you can give me and the rest of the public of Twickenham that we will continue to enjoy these things would be most welcome indeed. You say on your page that

  "I will be voting “Remain”, and I will continue to fight for
   Twickenham’s needs whether or not we stay in the EU."

Well, these are my needs.

If there's anything I, an ordinary member of the public can do to assist these matters, I would be happy to hear what you have to say.
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BBC Micro, TRS-80, ZX81, VC20, TI-99, and something else we have no idea; at the Science Museum in London.
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I entirely agree.

There's a growing trend lately where the more automation and technology we have, the fewer workers we really need; and yet we're still growing more and more people.

We're already starting to see the strain now, but sometime soon, maybe in a decade or so, something is bound to snap. We'll hit a point where there's more people than we can possibly manage to employ doing useful work.

As a society we need to start asking some serious questions now, so we have the answers ready before that happens.
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I'm considering how to drive a bunch of WS2812B LEDs (otherwise knowns as #NeoPixels) over DMX, with likely some kind of AVR chip inbetween. But see, I have this problem.

WS2812s want a very precise async serial signal to control them. A single bit takes 1.25µs, so a 24bit word for one LED is 30µs.

DMX-512 comes at 250kBaud (1 start, 8 bits, 1 stop), meaning a new byte arrives on the UART every 40µs.

Meaning: there's nowhere near enough time to multiplex them both at once. The moment I start talking to the LEDs I'll have to ignore DMX, and vice versa.

This means talking to 120 of my LEDs takes 3.6ms, reading an entire DMX frame takes 20ms; during either of which I can't be doing the other.

My current options seem to be:

 a) Read DMX continuously, ignoring the LEDs, until DMX says I should do something; do that thing by talking to the LEDs and ignore DMX, then swap back

 b) Split DMX and LEDs across two chips, because in practice I can ignore most of the DMX most of the time, and just pull out the single intensity channel I need to control the LEDs.

Does anyone have any thoughts?
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I've been trying to get this SSD1306 OLED display to work. All attempts so far have failed to actually get my data on the display.

I can easily write to the control registers - e.g. to set brightness, scrolling, invert, etc... Just I can't make any data appear. All I seem to get is random noise that was in GDRAM at the time. This both from custom code talking I2C via the Bus Pirate, and in a last-ditch attempt, this photo here showing the display hooked up to an Arduino Mini, running Adafruit's example code (see

I begin to wonder if my display unit is defective somehow and is unable to write to GDRAM.

Anyone have any last ideas before I give up and buy another one?

Edit: Not shown in the photo is the 4.7uF decoupling cap or the two extra 2.2k pullup resistors I just added to the I2C lines. Neither seems to have made any difference.

#electronic #microcontrollers #arduino #Adafruit  
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Clicking the publish button on ConnectBot v1.8.2 at the pub!
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In preparation for the v1.8 release, we are asking for help translating the Play Store descriptions. Every effort is appreciated!

If you don't want to register for Launchpad, you can post the translations as comments on this post and we'll put them in.
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