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James Ots
289 followers -
Husband, Father, Guitarist, Android Developer, Photographer, Runner, Cyclist, Son, Brother, Son-in-Law, Brother-in-Law, Cousin
Husband, Father, Guitarist, Android Developer, Photographer, Runner, Cyclist, Son, Brother, Son-in-Law, Brother-in-Law, Cousin

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On Thursday at lunchtime I had to make an 'emergency' trip to Packwood House, about 20km from work. The rest of my family had gone for a day trip but had forgotten to take Billy Beaver, the cuddly toy my son currently has for being Beaver of the Week at the moment in his Beavers group (Beavers is the part of Scouts for 5–8 year olds). So I was called up and asked if I could go home, pick him up and deliver him to them. As it was a nice day I could hardly refuse the chance to go for a nice 45km lunchtime bike ride, which was made all the better with the freshly roast beef sandwich and potato wedges which my wife had bought and was waiting for me when I got there. And I think having a cuddly toy stuffed in the back of my cycling jersey seemed to make drivers give me a wider berth than usual, for some reason!
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22/04/2017
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This is the finished PCW serial port. It started on stripboard, before I had it made as a proper PCB. The first PCB had a few mistakes on it, so I fixed them, moved some things around, added LEDs and labels, and had it made again.

The Tx and Rx LEDs aren't particularly useful — as well as being on by default and turning off when data is being transmitted, they don't change state for long enough to be noticeable at anything above about 300 baud. It's vaguely interesting to see at very low speeds though. The RTS and CTS LEDs are a little more useful.

It also only seems to work at 9600 baud and below, although I'm pretty sure it worked at 19200 on the original stripboard version, albeit unreliably. I'm not sure why that is.

I now have 9 spare PCBs for this serial port. I wonder if I should sell them on Tindie?
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The edge connector for the Amstrad PCW serial port arrived, and it fits, thus proving that I both know enough about KiCAD to create a footprint, and that I can read a datasheet. I wasn't totally sure I'd both read and entered everything in the correct units, but it turns out I did!
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The PCW serial port works! Well, it is recognised by the PCW as a serial port, but the d-sub connector hasn't arrived yet, so I don't know if it will actually communicate! I also don't have the edge connector yet so I don't know if I've got the pin spacing right.

It didn't work to start with, so I compared my circuit with the one I had on stripboard and discovered there were quite a few differences. I turns out after I'd made the working stripboard design then I'd made some 'improvements' in Eagle which broke the circuit, and one mistake when copying from Eagle to KiCAD. A few bodge wires later and it works (appears to work).

I'm now going to do a new, improved circuit board and get it made. Not because I need to (unless it turns out I have got the pin spacing wrong), but because it's good to have some more practice before I move on to some more complicated boards.
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25/02/2017
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This was actually a few weeks ago, but I've just hit another milestone on my bike. Yesterday, however, I didn't get to ride to work, thanks to 'Storm Doris' — I thought I might get blown off my bike (or at least blown into traffic), so I ran to work instead. It was quite hard work in the wind (and even harder work on the way home, thanks to my tired legs), so it was nice to be back on bike bike again this morning.
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A while ago I built a serial port for my Amstrad PCW on stripboard, which worked, but was a bit messy.

Recently I switched from using Eagle to KiCAD for circuit design and discovered that it was much nicer for laying out PCBs, so I decided to try making one of my more simple circuits before I try to make a board for my Z80 computer. So I created a PCB design, uploaded it to +SeeedStudio a couple of weeks ago, and this morning the finished PCB has arrived.

I think it looks quite nice (especially since it's my first attempt at PCB*), but until I get a couple of back-ordered components from RS I won't actually be able to tell if it works or not.

(* It's actually my fourth attempt at laying out the PCB in KiCAD, but the first one I thought was good enough to be made.)
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24/02/2017
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I just watched an entire film in German (Umweg nach Hause, or The Fundamentals of Caring in English), without subtitles, and enjoyed it. It'd be interesting to watch it in English and see if the film is the same, since my understanding of German is still rather sketchy, and my brain may have been filling in the gaps with its own version of the film for all I know.

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I just spent two hours changing my tyres. I hate fitting the Schwalbe Winter tyres, and I hate cycling on them, but when it's icy they mean I can carry on cycling, so it's worth it.
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03/01/2017
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New mudguards! So far, the SKS Raceblades seem to be much better than the Crud Catcher Roadracers which I had before, which I could never get to stop rubbing. All set for the milder winter days now (on icy days I'll ride my TriCross with Schwalbe Winter tyres instead.)
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I'm sure this must have been shared on here at some point, but if it was I must have missed it. According to their facebook group the boards are in production for testing and the crowdfunding campaign should start soon, which I'm extremely interesting in. (I'm also quite glad I've only just discovered it, as it means the wait won't be as long for me!)
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