A Long Story...

I've had an Arduino for a year or two, and fooled around with it, and not blogged anything. Bad me.

So here's the blog...

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Replacing Coffee Machine Pump (Dualit Espressivo)

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My 5 year old Dualit Espressivo broke on Saturday - disaster!! I was in the throes of making a coffee when the pump stopped, so no steamed microfoamed milk... Off with the back, check of voltages etc., taking extreme care because 240V + H2O is a Bad Thing. I located what seemed to be the pump, and there were volts on the terminals. Hmm. It’s an Ulka EP5FM according to the label. Google... Many people offering to sell me one, but the guys at ulka-ceme.co.uk aka Scintilla Pumps are the UK distributors. They sell a whole range of this type of pump, and the documentation shows that the crucial points are voltage/power, pressure (15 bar) and duty cycle (2m on/1m off). I can buy one online but I call them... they’re about 15 miles away, and are happy to sell me a replacement. We reckon it’s worth a lunch trip, so bowl over and it’s only £16 direct, vs £19.60 mail order. Done. The expensive part was lunch - £50!! Planning to skip dinner though... New pump fitted - looks like the old...
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mDNS, Sonoff-Tasmota, code spelunking, and when is a host not a host! Or a domain a domain...

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Multiple SHT30 sensors on a single I2C bus with Sonoff-Tasmota

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I have a hankering to measure the input and output temperatures of my condensing boiler, in order to determine if it's likely to be actually condensing at any time. I have lots of SHT30 sensors, which attach handily to NodeMCU units. However, running 2 separate rigs, one each for input and output, means that temperature measurements will not be synchronised, which doesn't account for the action of the boiler and its heat output rate of change. It appears that the SHT30 has two I2C addresses (0x44 and 0x45), which are available on the Wemos D1 knock-offs that I have. So I started out by modifying one to use a different bus from the standard one - this is easily done by bridging a link with solder. I then used 2 NodeMCUs running together to check that the newly addressed device is actually detected and works. It does. Pair of NodeMCU/SHT30 setups in action Close-up of SHT30 devices -RH(44) has soldered address link (circled) So, let's see what we can do, eh? I...
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