Thankfully the fix is simple, remove the libs from /usr/local/lib that are conflicting, and don’t use CPAN

This may break your Perl module it installed, but hopefully will restore the usability of your system. My recommendation would be to only use packaged versions of your Perl modules to ensure system integrity, save you some headaches later in life.

She did warn me before hand that its not quite as simple as riding a bike.. I was a little skeptical, shirly (her name isn’t Shirly) its all about gyroscopic forces and what not.. yeah, I was wrong, it’s all kinds of scary.  I of course got lots of support from online friends who demanded videos of my efforts, clearly not looking to see my mangled self, oh no!

Needless to say they were disappointed with the lack of falling but called me out for the use of hand on wall for stability!  Alas that evening I had limited time so could not push further.. so tonight, with determination.. I DID IT!

Yeah, wobbly as hell, but I am pleased for my first attempt without holding for support, managed about 37MPH too, plenty left in the legs but need to work on my stroke (another plus for roller riding).. I also need to get a fan as I soon warmed up to a sweaty mess.

Onwards and forwards!

Crazy busy at work with all mannor of projects, all far too secret for me to divulge here   But those have to come second to what is really taking up my neural ticks in thought process..  My oh so lovely girlfriend… yeah yeah, I know, soppy blergh etc.. but this is a tad different!

How so? well (as I am sure anyone who has suffered being in my presence for the last few months can attest), she is representing Great Britain at the Paralympics!  So proud of my good lady am I! Hope you will join me in cheering her on, I’ll be there myself in person cheering away, for those who are not, I believe all the coverage is going to be on Channel 4.  Her events are Track cycling, Tandem B/Vi 1KM TT on 31st of August at 9:30 and the 3KM Pursuit on the 2nd of September at 9:30 with the final on the same day at 14:00.

Her athlete profile on Channel 4 is here

So proud, I am a very lucky boy!

As the samples used are all 8 bits, a 16bit word can obvioulsy hold 2 samples, thus half the number of time the DSP has to talk to main RAM, reading the sample data once from main RAM and then the next subsequent read from it’s own cache.  As the resampling will in some cases simply need the same sample n number of times, this saves a chunk of bus time.  The reason I chose 16bit originally is the DSP only has a 16bit data bus connection to the main RAM (more of an IO port style connection IIRC).

Thinking about it, I am assuming that 1x 32bit read will take less system resource/bus time than 2x 16bit reads seperated by several ticks of other instructions.  Especially as whilst the DSP is making its 16bit reads, nothing else can be using the bus and will need to have been paused.  I am most impressed with how little additional code was needed to support this change, the current code has to translate the requested sample address to determine if it has it in cache, then retrieve just the single byte from the cache that is needed, it all came together very nicely.

I imagine the overall gain will be quite minimal, but every little helps, I have sent the code off to be tested in a real world environment, hopefully there will be some positive results

Next up is a complete rewrite of the render subsystem for the sound engine to effectively invert the way the cache works and hopefully keep the DSP off the bus even more!

Last few days have been spent faffing with the Vibrato effect, this effect takes two parameters, one sets the frequency and the other the amplitude of a pitch distortion of a playing sound.  It always gives me a headache to code, and as my OCD tends to want perfection that irks me further.  The amplitude is based on 8ths of a semitone, of course as these are calculated by a non-linear expression it requires some look up action.. but then if you are coming off the end of a slide, there is a good chance that the current playback period may not actually exist in your lookup table.. so I engineered a less than accurate, but hopefully good enough work around.

So I compute a percentage of the current period which is approximetly the same size as an 8th of a semitone between the current note and it’s neighbour, so whilst not 100% accurate, it works irrespective of the actual playback period and gives similar audiable effects.

Overall I am quite pleased with my solution, that combined with the other effects I have added support for and the improved timing code so that non 50Hz timing based modules play correctly make quite a lot of modules that sounded a bit iffy now sound bob-on..

Of course this has meant I have had to rethink a lot of previous ideas, had new ideas and subsequently need to re-write a fair chunk of the code before I progress further.. or I will claw my own eyes out, but its all going nicely and I have my most hated effect completed, so the rest should be easy now… should be…

Anyone who is interested you can download it from the website here, complete with a changelog

Whilst these are steps in the right direction, they lacked a certain something, I wanted something a bit more.  So in an attempt to find this I had a mooch around on the British Cycling website.. and have now applied for a racing License! hoping to take part in some national races and see how I do in the rankings

My plan is to go to see a a race on Tuesday after work, and if possible to take part in it myself the following week   I’ll post here following that I think.

Exciting times!

The event has 3 flavours, 13 miles, 26 miles or 52 miles… of course, I went for the 52 mile option this also brought an additional caveat in that I was required to maintain a speed of 18MPH or faster on average to complete the course in time!  I thought what the hell and signed up anyway.

The 52 mile ride started this morning, setting off at 8:00AM with rider assembly at 7:30AM, of course I got a whole 5 and a bit hours sleep before hand :/ and probably didn’t eat the best of foods, but meh don’t want to make things easy for myself now do I!  I was hoping to wear just the event Jersey and my shorts, but despite the sun it was a little cold so I ended up needing my cycling jacket too.. so glad I did that!  My toes were frozen and I never really got too sweaty, not too bad a temp for the ride really (BBC Weather stated around 8 degrees C to about 12 degrees, my Garmin was saying about 13 degrees).

Once we set off the ride out was really rather enjoyable, this being my 1st ride of this type and my 1st real experience of bunches and chains.  WOW! how much fun are they!  Riding along the A57M itself is fun, but when you are doing 30MPH easily, slipstreaming off another rider or two.. awesome!  Which reminds me of another cool thing, the noise.. near silence (other than some chatting).. just the faint hum of wheels on tarmac.  I was quite pleased that I managed to get right up to the lead bunch at the start quickly and without having to push myself!  It didn’t last after the pinch point at Media City which almost has the riders single file onto a foot bridge I just lost the bunch and ended up riding solo.. and into that bloody wind, and up hill..   So this really sucked the life and speed out of me.

Thankfully after each lap I learnt a bit more and started looking for wheels to hang off of, actively chasing after a chain to sit in its slip stream.. I was quite pleased to realise I had someone slipstreaming behind me for a fair turn of the route, spurred me on a little to maintain the 25MPH I was doing!

Towards the end of the ride I was pretty tired, this was the fastest, non-stop, constant peddling ride I have ever done, my Manchester to Blackpool rides of previous years have been slower, and involved stops at lights and feed stations.  Today I stopped after the 1st lap for a loo break and that was it!  I didn’t free wheel too much just kept spinning away.  Another boost to my speed and drive was switching the screen on my Garmin to show the current time and my ride time.. until that point I had been concentrating on my average speed more than anything, so had no idea of the time.  Switching to see the time revealed it was a lot earlier than I thought and indicated that I was doing better than I had thought! this really helped spur me on!

A brill day out, lots of fun, I will doing another of this I think.  Which only leaves my stats really…

I completed the full ride in 2:42:36 with splits of 42:08, 40:08, 40:39 and last lap of 39:41  (found a good chain that got me most of the way back )

and the stats from my Garmin via Endomondo are:

And my best distances were:

Now, I think I’ll go have a bit of a rest

Got stuck into working on some long overdue tweaks to my mod player routines these last few days, finetune and BPM based timing.  Both of which I have now solved and implemented (although some additional tidying will be needed in the future!).  Unfortunetly both require lookup tables at the moment due to the chunk of maths or brute force needed to compute the tables, it works, and if I figure a nicer solution I can always add it later.

Both of the additions only required less than 10 lines of RISC code each to make use of their LUTs, a little bit of buffer space and a bit of main RAM, and bish bash bosh things sound that little bit better.

Still a few more effects I want to get finished off before I roll out this release of the SoundEngine however, but it is being worked on!  I have a chunk of time coming up where I should be doing a fair amount of work on it, so who knows, could be a new SE release in June! watch this space!.. well watch the U-235 website really

Thought it might be fun to blog all the ones I have had go sideways (a little bit) when they were supposed to go straight.  So in no real order they are:

• Front wheel drive car with use of handbrake..
• Front wheel drive car (no use of handbrake!)
• Rear wheel drive car
• Mountain bike (YAY FUNS!)
• Road bike
• Road Tandem bike ( )

I think the most scary was the tandem, there was a brief moment of ‘oh crap, this is going over’ which was audibly the thoughts of the stoker from her reactions at the time too   It didn’t we were awesome, no it wasn’t intended

I am not 100% certain if this is entirely the RISC CPU bug or MADMAC being a bit pants at alignment, but it is possible to generate ‘fun’ alignment issues in your code by simply adding or removing a nop (or other similar 16bit only instruction).  The instruction doesn’t need to be called even! that’s how much fun this is!

From what I can tell it seems that jump instructions are particularly fussy about where they are jumping to, so it is possible that by adding/removing a 16bit instruction you will move a jump destination into one of these ‘un-desired’ addresses and hey presto your RISC code suddenly stops working, or does something weird.  Even though you haven’t changed anything that should cause such behaviour.

So if you are playing with Jaguar RISC code and using jumps and sometimes it randomly seems to stop working but then work again, this could be the cause.  How do you find which jump is being affected? trial and error is my best method, or add a nop just after the code you modified (doesn’t need to be the executed code block), one at a time until your code magically starts working again :/

One day I’ll fully track this down and come up with some fix/work around.. probably   Until then, keep hacking!