Friday, November 25, 2016

C64 repaint - 2nd Chapter

Well, sometimes we simply _have to_ experiment and try out new things. There's an infamous saying in my hometown: "Once in a lifetime you have to try everything you can. Except folk-dancing."
So, here it is, I'm almost finished with repainting a C64. Yes, I know, this is not the first time I'm repainting a C64 but this is the first time I'm doing it right. At least I tend to think I'm doing it in the right way.

The case was yellow. Very. Yellow.
Keys were dirty. Very. Dirty.
There was no sunshine for a long time, I have no balcony or garden area where I live.
This made me to do it, even if some might say I'm vandalising the good ol' sixtyfour.
Whatever. Once in a lifetime you have to try it. It's still not dancing. Folk-dancing.

First question: what color shall I use?
How about the signature Commodore blue-red? -ish. It's hard to find matching colors, especially by looking at some pictures on the internet. They can be misleading, however, maybe accurate as well. So I gave a try (still not dancing) to Plastikote Satin Navy Blue and Satin Wine Red.

Well, they are definitely not similar to Commie's blue-red but these were the better-looking colors.

Dismount C64, clean it with warm and soapy water. Let it dry out properly. Start painting.
We need a place where it's possible to use the spray paint without damaging walls/furniture/lung/etc...
Ok, whatever, I went down to the front of the building and painted the C64 with people staring at me. I became kinda famous because at the second round I've been asked what the hell I'm doing and somebody even made a selfie with me in the background, spraying.

Anyway, sprayed the case on the street but let it dry inside the flat. Not 100% satisfying but worked well, I just had to keep in mind to open the windows from time to time, to get rid of the smell of the paint.

Yaaay, this spray paint is awesome. Not just because the color is pretty but the paint gets even on the plastic. Push the button, spray it, move your hand from left-to-right, repeat. It's done.

1 day was more than enough to let the first layer dry out.

Nope, I have nothing to do with football, nothing to do with Barcelona. It just happened to be similar to their colors. I'm especially proud of the red-blue crossing on the top cover. It's smooooooth.

After a week of leaving it dry out - it wasn't gluey anymore - I started to assemble it.

And in the meantime SIDfx arrived! Why not make this C64 even more special by mounting the SIDfx inside this machine?

Great. It fits. FYI: you should use 6mm drills for the jack connector and switches.

Almost done. The keyboard looked pretty off whit the usual white-yellow-ish keys. I even tried with black-brown keys but it still looked ridiculously off. I'm still waiting for the new C64 keycap set, probably they never going to arrive... so I didn't want to order another set.

Brilliant idea, let's use the (pretty a lot) remaining of the red-blue spray paint. Similar way, similar method, similar technique.

Add a layer of matte paint and that's it. Looks better and brighter in real, this picture can't give back the proper look of it.
I still need to find a solution to the keys, or I just simply have to learn to type blind. Oh, and a nice LED that fits this color-scheme.

I'm going to post about the SIDfx next time, will write about my experience after a deeper test.
See ya' there.


Today's music: SIDRIP Alliance - 2nd Reality (remix)

Friday, November 11, 2016

C64 music vs. GoatTracker

We live in a world where it's possible to compose Commodore 64 music basically on any platform. I'm not sure how popular SID music is compared to the Gameboy chiptunes. It would require some research to find it out so let me skip this part and jump straight into music editors and leave research for another day.

Back in the good ol' days I 'composed' music with Future Composer and various versions of Demo Music Creator. Since then, I've used and still use SID Wizard which is a great tool and it's up to todays standards in composing C64 music.

Those were the days, when I started to play with those editors without any knowledge about the SID chip and without any documentation given to the tools. Now it's not even unusual to create a C64 music on PC, either with loading a native music editor into VICE or similar emulators. Or just simply using a tool that was made for composing SID music on the PC/Mac and saving it in C64 format.

One of these tools is Goat Tracker. Widely used and loved together with CheeseCutter, now it's quite simple to make some noise without having a real breadbox.

The main reason of today's post with this introduction is to mention those music editors AND show you a great example of using Goat Tracker by my good friend, NecroPolo. He's got some serious guitar playing skills and talent in making the SID bleed - in the meaning of creating unusual sounds and using the SID as it was his beloved guitar. And distortion. Because metal, that's why.

His passion is to release videos of his C64 tunes from time to time, let me share the latest one here:

Now this is how Goat Tracker does look and sound like - good old tracker interface with SID registers for tweaking the sound and all with hexadecimal numbers of course. I recommend to subscribe to his channel as well.

I, hereby save and publish this post with recommending to check NP's other videos and have a listen to his music:


Saturday, November 5, 2016

Amiga 500 vs Gotek drive vs KMTech extension board

Previously I wrote about the Gotek drive with Cortex firmware for Amiga computers. It works like a charm, the only issue is the placement. I wanted it inside the A500 without drilling additional holes on the original case so I was looking for a solution.

Actually, I found a great solution quite fast. Googled "mount gotek into amiga 500" and got a bunch of forum posts and this: KMTech's Gotek Extension Board

This is a nice looking board that is easy to assemble into the A500. I don't want to go into details, their webpage shows the installation steps nice and clear. A little bit of soldering required but don't worry, you can do it if I was able to do it :)

I simply followed the steps and mounted the 2 boards together into the Amiga:

That adhesive stuff keeps the boards in place. It's not super-strong but strong enough. You can try to hotglue them to the plastic, it'd be definitely stronger, however, permanent.

Of course, there are many options to mount the Gotek inside the Amiga, this is one of the easiest and fastest solutions. I'm very happy with the result, it looks good and the plastic case is still intact.


Today's music: Driveclub OST

Sunday, October 23, 2016

Gotek vs Amiga 500

The Girlfriend 500 - sounds like a cheesy advertisement in one of those weird TV shows, right? - is a beautiful computer of its time and nowadays it still has the charm. I remember, I was around 14-15 years old when one of my mates bought an A500 and we played games, watched demoscene productions all weekend long without pause. I had a C64 back then, we used 386 PC's in school and the difference between the computers were remarkable. While I was still in love with the C64, the PC's were kinda soulless, or how to describe it. The Commodore computers definitely had somekind of charm and personality. Not just because the audio-video capabilities but... I don't have words to describe it. They were just simply better :)

So, I have an A500. Cleaned it from top to bottom, from inside to outside and... It doesn't load any software from any disk, while the same disks work without problem in my A1200.
Captain Obvious here, the A500's floppy drive is broken.

I've read a few articles about fixing it, but I decided to order a Gotek drive with the Cortex Amiga Firmware. It's a clever device and a clever new firmware that might not work with the A500' without further modification. There can be an issue with older Kickstart and/or using the Gotek as additional (DF1) floopy and not primary (DF0).

I simply replaced the broken floppy drive with the Gotek:

And it works. Just, simply works. It's sooooo comfortable to copy .ADF (Amiga Disk Format) files to the USB stick and switch whenever it's needed.

However, the first setup of the USB stick wasn't obvious on the first look but fortunately I was able to gather all the required information from various forums.

The Gotek with Cortex Amiga firmware is not enough on its own, the USB stick needs a file called SELECTOR.ADF.

You can download it from Cortex' page, don't forget to rename the extension to .ZIP: cortexamigafloppyemulator_v105a.docx

The SELECTOR.ADF can be found in \\CortexAmigaFloppyEmulator\Bootdisk\ folder.
By default it is an empty disk file.

Next step is to download games, demos, whatever you want to run on the A500. One of the best source of demoscene productions is
Use the "Search Box" feature on the top-right corner of the page.

I downloaded ~100 demos for the A500 (OCS/ECS), but oh noes, a lot of them were .DMS and not .ADF files. This is a compressed Amiga Disk Format, WinUAE can read it without any problem but the Gotek can't. It works with .ADF files only.

Don't worry, there is a solution for that!
ADF Opus and its batch convert option did the job and converted the DMS files to ADF in a few seconds.

Now we need to create a "tracklist" that the Gotek and its SELECTOR.ADF would use for listing/tracking of the .ADF files on the USB stick.

There is a tool called Amiga Gotek Cortex SELECTOR.ADF Edit (pretty long title but it perfectly describes the tool).

  • install SELECTOR.ADF Edit
  • copy .ADF files, including SELECTOR.ADF to USB stick
  • run SELECTOR Edit
  • quit SELECTOR.Edit
  • pause Kaspersky and/or any other virus scanner
  • run SELECTOR Edit again

The tool scans and lists all the .ADF files on the USB stick, now you can move the files from the right-side to the left-side, then click SAVE. This will be your "playlist" and you can select the disk image files with the small buttons on the Gotek drive.

Insert the USB stick to the Gotek, boot up the Amiga. The SELECTOR.ADF will start automatically and you can browse the list and run any of the .ADF files. Yaaaaay, happiness, flawless victory.

I've spent the whole night with watching some neat demoscene stuff and enjoyed the same goosebumps as I had X years ago.

Sushi Boyz by Ghostown:

Rink a Dink Redux by Lemon:

And a lot more of course :)

Now the next step is to mount the Gotek drive into the A500 without drilling, without destroying the plastic case. That's the story of the future, I'll share it with you once it's done.


Today's classic A500 demo: Enigma by Phenomena

Tuesday, October 18, 2016

Saturday, October 15, 2016


A while ago I posted about Blu, my blue C64C. I made most of the SID comparison recordings with its 2 SID setup and, because the SID is a fragile chip I wanted to have something that would protect its circuits.

I asked my good friend Hermit (he is one of the developers of the new SwinSID Ultimate) if he's got an idea how I can do it. He took the question very serious and designed a circuit:

Let me copy-paste his words from CSDB, where the official release have happened:

"I designed this simple SID-protector some months ago as Vincenzo needed some protection for SIDs to record safely. I tested the circuit in ngspice (SPICE circuit simulator linux implementation), and Vincenzo built and tested it on real hardware. He didn't try to stress-test it for obvious reasons (too many SIDs died already in C64 history), but the circuit simulation shows that this simple circuit protects SID's output from overvoltages and reverse voltages/currents. If the diodes are of Schottky type (with enough reverse breakdown voltage for the task), the circuit can have less impact on the output signal due to the series diode and more protection in the negative voltage region on SID-output. 50V and more breakdown voltage diodes are preferred because in practice phantom power around 48V is the biggest that a mixer or other devices can drive to the C64 output by accident. 
If the diodes are normal-type (e.g. 1N4148), then D2 in parallel with the Zener doesn't do much and can be left off...
The circuit only worsk with DC output of the SID (or maybe the transistor current amplifier output) and provides DC output which should be filtered with a series capacitor to remove the DC component of the signal or connected to the transistor current amplifier in the C64. The latter hasn't been tested yet, Vincenzo simply used RCA sockets to directly drive the outputs out from the C64... That worked with both 8580 and 6581 SIDs despite the 6581 having incomplete (non-complementer) output...
We hope this can prevent some further SID-deaths for people who try it...

The only difference to the schematics is that I've used 1N4148 instead of Schottky diodes.
After testing this circuit I experienced a bit of volume-loss on the output level, but basically that's it. It worked so far without any further complications and it's small enough to fit inside the C64.

ps: in case you were wondering who is that Vincenzo guy Hermit' mentioned, FYI it's me, vincenzo /StrayBoom Music. composer, sound designer and owner of this blog.


Today's audio-visual experience: Offscreen Colonies by Conspiracy

Wednesday, October 5, 2016

C64 C - new look with old board

Ever wondered how to identify the inside of a C64 by just looking at it from the outside?
I can highly recommend Ilesj's article to start with because it gives you nice examples with photos and explains the differences well.

I recently get my hands on a C64 C, it looks nice from outside, has just slight yellowing. Keys are stiff, on/off switch isn't lose so I was sure it will just simply work when turned on.

Oh yeah, it did! Nice red LED, old-style keys, C64 C is written on the back. I quickly loaded my favorite test track (Jammer - Club Style) to hear how the SID sings.

I immediately realized it's a 6581 because of the filtered sounds and the fact the track is kinda broken. I also made a guess that it's a 6581 R4.

Hint: read my previous articles about comparing different SID revisions, search for "C64 SID shootout" in this blog. Cheers.

Opened the case, removed the shiny alu-cover aaaaaand...!

It's an "old" board, Assy No. 250466. Youngest of the old boards. And have a closer look on the SID:

It's a 6581 R4AR aka. R4 Advanced Resonance. My guess was close enough, right?


Today's music: BitJam Podcast #195 - Manifesto - Dane's Mix From X2014

Saturday, October 1, 2016

Back from holidays with a new post

After a very exciting but also exhausting summer time the Kompjut0r blog returns with new posts. I had the chance to take a photo of my current collection and would like to share it. I'm not going to fight for "The Biggest Obsolete Computer Collection" title, it's just a bit of bragging about my stuff because I'm proud of it.

Most of them are in good condition just need cleaning inside and out, but still need to test a few of the C64's since they are newcomers and I never switched them on.

ps: I'm looking for a bigger flat and a huge shelf to store all this stuff


Today's music: Surprise, just click and pump up the volume

Tuesday, July 5, 2016

C64 repaint

After a few weeks of silence - pun intended, the previous posts were about music - I'm back with a completely different topic of renovating retro computers.

I've posted a few pictures about a C64 C months ago in this post: C64 C - I'm blue, I'm blue!
Since then I made progress with renovating the scratched case and decided to try out something new: repaint and make it unique.

Started with a warm bubble bath - no, not me, I washed the plastic case in a warm, soapy bubble bath then let it dry out. Some very fine sandpaper helped to soften the scratches, tho it wasn't enough to completely remove them. Well, my patience was over as well, so I went online to check available spray paints.

Went with a very simple grey colored spray can, he only criteria was to be able to paint plastic with it. The whole C64 case was a wreck already so I had nothing to lose - I thought.

Bubble bath followed the sandpapering session, had to clean it before painting. Then, two layers of spray painting has been applied, including 2 days of drying between the 2 layers.

After the second layer of grey paint I left it on the balcony, fortunately there was no rain, only calm wind that helped with drying.

Grey base. Well, looks better than the original, scratchy surface but it's still not enough. What to do, what to do..? Add colors! And add some well-known game characters.

It seemed to be a great idea but wasn't easy to realize it. It's not easy to draw without any talent... Anyway, I had to try it.

And failed. So I repainted the whole thing with grey again.

And then asked my wife if she wants to help me with drawing and she did offer her help! I'm a lucky man.

We chose a few classic games like Bruce Lee, Pacman, Space Invaders, Inter Karate and printed the characters on an A4 paper (thanks to Poison for helping with setting up the proper size).

It took a few hours to properly draw and fill the characters but I think it worth the effort.
They looked really cool but overall, it was just a few black characters on a grey plastic so we decided to fill 'em up with some colors.

Looks a bit abstract, right? Yeah, it's not _that_ great as I had it in my vision but it's still looking good and what's important: it's unique and it's the first one. The next one will be better, because I won't stop here. You've been warned.


Today's music: BRUCE LEE (1984) - LukHash REMIX (performed by Kung Foo Panda)

Tuesday, May 10, 2016

C64 SID Shootout part 5. - SID 6581 vs. SwinSID Ultimate (in 6581 mode)

It seemed to be a good idea to give another round to the SwinSID Ultimate because, did you know it has 6581 mode as well? Yeah, this little gem is capable of emulating both 6581 and 8581 revisions. However, its main mode is 8580 - as CodeKiller explained it to me.
Also, 6581 mode is not complete yet as there were not enough memory to emulate filter distortion and some other bits as well. Let's see (hear) how accurate is SwinSID Ultimate's (SSU from now on) 6581 emulation.

Nope, I won't normalize the recorded audio files. Yes, I know the loudness level is different on 6581 and SSU. Still, in my opinion the true comparison is WhatYouSeeIsWhatYouHearWithoutAnyModificationHearingTrueOutput. That's it. You have volume control on your audio equipment, use it to compensate loudness diferences.

The following lines needed to switch the SSU to 6581 mode:
POKE 54272+29,ASC("S")
POKE 54272+30,ASC("E")
POKE 54272+31,ASC("6")
Reset C64.

To switch back to 8580 mode just simply write "8" instead of "6" into the third line. It's quite simple, isn't it?

I used Breadbin with the most loved SID 6581, the 1485 so the expectation for SSU is VERY high. Ladies and gentlemen, make your bets. Based on previous tests, what do you think? How SSU can meet the expectation?

Ready? 3... 2... 1...

Chris Hülsbeck - Hollywood Poker Pro main - SID 6581 1485

Good ol' Hollywood Poker with the dance animation scene..! (and more but that doesn't matter right now)

Chris Hülsbeck - Hollywood Poker Pro main - SwinSID Ultimate - 6581 mode

I'm going to repeat myself: impressive! The original SID is a bit brighter and the filter seems a bit more opened but SSU is great as well. Sounds like differences between 6581 revisions.

MSK - Land Of Illusion - 6581 1485

It's a multispeed track. I didn't dig into the code to check it but it's clearly audible, especially on some arpeggiated notes. Nice track, nice sound trickery.

MSK - Land Of Illusion - SwinSID Ultimate - 6581 mode

Wow, nice. Flawless multispeed reproduction, the only noticeable difference is the filter. Again, it's a minor thing, SSU's filter doesn't have distortion and it seems a bit more closed or deeper.

Drax - Drudgery - 6581 1485

This track is something special. Not just because it's beautiful and the bassline is extraordinary, but it also has nice filter variations between bass and arpeggios.

Drax - Drudgery - SwinSID Ultimate - 6581 mode

SSU did it again, same result as before: waveforms reproduced well, filter is a bit different but has that mojo. Actually, I like the deeper filter in this track more than in the 1485 version.

Jeff - Blowing - 6581 1485

This. Is. One. Of. The. Best. C64. Tracks. Ever. (personal taste of course, don't take it too seriously) Perfect dance music, awesome sounds, great melodies.

Jeff - Blowing - SwinSID Ultimate - 6581 mode

Again, question of taste matters. Which one do you prefer? The original with a bit more opened filter or SSU that is a bit deeper-boomier?

And now, here comes my favorite 6581-breaker - that is actually a music written on a 8580 SID. Guess how SSU delivers a 8580 track in 6581 mode. Will it break as it would on a real 6581? Or will it play perfectly, because this is an emulation?

Jammer - Club Stylier - SwinSID Ultimate - 6581 mode

Aaaaawyeah, it breaks as it should! :) Honestly, I expected it would play nicely but it didn't. It makes sense, SSU is switched to 6581 mode and a real 6581 breaks this track, so SSU did it as well.


I wanted to write something nice as conclusion but I realized it's not necessary. The SwinSID Ultimate is the current best SID alternative if you want to replace your broken SID in the real C64. It doesn't matter which revision you prefer, SSU's performance is outstanding either in 6581 or 8580 mode.