Wednesday, April 29, 2015

A bit of hardware tinkering

and not the usual computer hardware, that is.

I was asked to create muscle power to electricity demonstration device, basically pedal to light a light bulb. Easy enough, take a old exercise bike, strap an car alternator on it, some wires and a light. Right ?

The first prototype works as can be seen on this short video:

Next up is to make it more robust and figure out some foolproof way to handle the power pulse the alternator requires to get magnetized.

I'm thinking about using an Arduino (well, surprise!) to sense when the wheels are turning and if there is no power generated then give a short pulse to magnetize the alternator. Also voltage, current and watt display might be a nice addition.

Monday, April 20, 2015

Prestashop front-end stuck in maintenance mode ?

Back-end says shop is enabled but front-end is stubbornly stuck in maintenance mode ? Going crazy ? Don't panic!

Look into your Prestashop database, specifically the ps_configuration table.

select * from ps_configuration where = 'PS_SHOP_ENABLE';

You might get something like this:
| id_configuration | id_shop_group | id_shop | name           | value | date_add            | date_upd            |
|               30 |          NULL |    NULL | PS_SHOP_ENABLE | 1     | 0000-00-00 00:00:00 | 2015-04-17 13:24:22 | 
|              476 |          NULL |       1 | PS_SHOP_ENABLE | 0     | 2015-04-12 22:46:19 | 2015-04-12 22:46:19 | 
|              477 |          NULL |       6 | PS_SHOP_ENABLE | 0     | 2015-04-12 22:46:19 | 2015-04-12 22:46:19 | 
|              478 |          NULL |       7 | PS_SHOP_ENABLE | 0     | 2015-04-12 22:46:19 | 2015-04-12 22:46:19 | 

As you can see only one is enabled, other shops are not. The quick fix,  

update ps_configuration set value=1 where name='PS_SHOP_ENABLE';

should do the trick.

Monday, February 23, 2015

Jolla tracker music support package now available!

Sorry for the massive delay, just over a year or so... Anyway, now you can listen to your favorite tracker music files on your Jolla and feel all nostalgic!

Because of harbour limitations, mod-support is only available from openrepos.

Thursday, February 19, 2015

MSP430 Serial FATAL: cannot open /dev/ttyACM0: Input/output error

Getting this when trying to open the serial port to your MSP430 on a launchpad ?

FATAL: cannot open /dev/ttyACM0: Input/output error

The reason seems to be that a buffer on the serial converter gets full and the chip gets upset and fails.
But you can easily workaround it. Disconnect the serial pins from the "emulator" (why do they call it an emulator in first place, I don't get it, it does not emulate anything) part on the board by removing the jumpers.

Connect the USB cable to your computer and now open the serial device in for example picocom or some other serial app. It should open ok now.

Now put the jumpers back in, you should get your serial output now.

Wireless sauna monitoring system using MSP430

I've been planning, for a long time now, to create a monitoring system to our summer cottage. Features would include monitoring of temperature of air and lake water (the cottage is by a small lake) and why not air moisture and barometric presure just for fun.

Also monitoring the sauna temperature in some inteligent way, for example for informing to add more wood and "Sauna is ready!" signal.

All of this would of course be logged on a SD and some way to view everything, maybe just a 16x2 LCD screen or perhaps something a bit more cool.

Anyway, finally some progress, a wirebundle of a wireless sauna sensor. Basically just a MSP430 launchpad, MAX6675+thermocouple wire and a NRF24 radio.

I'm using energia, sketch will be up soonish on my github.

It seems to be sending, I haven't tried the RX part yet :)

Tuesday, February 17, 2015

Interactive piste map on Sailfish OS

Found libosmscout a while back and that gave me an idea, but never had time to look into it properly. But last summer I tried making piste specific styles and it did what I wanted. Then I forgot all about it more or less.

But now I've been playing with creating ski specific stylesheets for a while now and it is starting to look like a nice piste map.

Today I got inspired to get the libraries and example QtQuick component up and running on Jolla. First test app was up and running quite fast.

Example map  data from Åre.

Test Mobile Åre piste map

Monday, February 09, 2015

A used and cheap Playstation 3, overheating and blinking Red Led, my solution

It seems I'm always 10 years behind with game consoles. Found a couple a weeks a go from a local ecorecycling store a used Playstation 3, a old big fat model one. And got it under 40€ thanks to eject button not working (that was an easy fix)

Of course, no controller and no games so that was another 70€... (I got GTA 5, the only reason to get a PS3 ;)

Anyway, it worked fine for a week or so, then started crashing to a blinking red led. Seems to be a typical error condition after a quick google on the issue.

I didn't yet get the dreaded yellow led so all was not lost. Opening it up my first impression: Whoever designed the case and cooling should be publicly humiliated, flogged and anything else that makes him/her feel the pain that they have caused to thousands of Playstation 3 owners.

Yes, there is a big heatpipe system and a enormous fan, but the there is absolutely no source for fresh and cool air. Espcially the holes on the right side are just for show, as they are more-or-less blocked on the inside. What the fuck where they thinking ? And the holes at the front, not much better, the circuit board blocks most of them.

Still, I did open everything up and the thermal pasting was also a crap job.
Thermal paste, a crap job by Sony

First I fixed that with fresh and properly applied paste. The next was to get some fresh air into the case. That easy enough, just needed to find my drill first.

Drilled holes just under the fan to get some air flow

The same with the side, drilled some hole in air blockers

This seems to have helped, no crashes after many hours of playing. Before it was around 2 minutes from game load to a crash.