SwinSID Ultimate

I’ve written about the need and importance of having a proper replacement for the SID sound chip few times before. So I won’t repeat myself on that, as this is going to be a lengthy article anyway.

Because what we have here is big news on this front.

A duo from Hungary, Máté “CodeKiller” Sebők and Mihály “Hermit” Horváth have been working on improving SwinSID, originally developed by Swinkels.

What they have come up with is a highly modified and expanded version of the Nano SwinSID, now called SwinSID Ultimate. The enhanced hardware is mostly developed by CodeKiller, and Hermit has rewritten a new sound engine almost from scratch. The aim has been to make a more compatible, more capable SID replacement than what the Nano SwinSID already was.

At least the list of improvements is impressive:

SwinSID Evolution

Since it’s initial release in 2010, the Micro SwinSID from Swinkels has gone through some improvements over the years. These improvements have come in form of both hardware and firmware updates.

Most obvious improvement was the change of form factor from the Micro SwinSID to the more familiar Nano SwinSID. Initially the Micro SwinSID was based on DIL-packaged ATmega processor making the board that housed also a full-size crystal oscillator and couple of trough-hole components almost twice as wide as the SID socket. Some time later a redesign appeared that was based on surface mount components, squeezing all the same components into a small PCB that’s no larger than a real SID chip. Or at least as long as only area is considered. Pin headers, components and jumpers make the board somewhat thicker.

Micro SwinSID and Nano SwinSID side by side. Both designs have the same components and features, except for the additional filter jumper in Nano.

During the first few years since the introduction, there was couple of official firmware updates. These firmware updates improved the sound emulation and compatibility with the behavior of a real SID chip, reducing the number of cases where Nano SwinSID would not sound or act ‘right’. Down the line there was also a feature update that made it possible to select the filter emulation between 8580 or 6581-like behavior using a jumper.

These refinements have improved Nano SwinSID, making it more feasible SID replacement with each improvement. Sadly there hasn’t been a new official, or publicly available firmware for the Nano SwinSID since 2012. As if SwinSID had reached its maximum potential with some of its flaws to remain.

This changed in 2014 when Máté ‘CodeKiller’ Sebők stepped up with a new firmware.

SwinSID analog controller hack

I’ve covered SwinSID micro and nano few times before. It’s a great idea – a micro controller based SID chip replacement, working as a spare part  for a C64 or C128, or as a substitute to some other application like a DIY-synth. For Commodores, it’s especially suited for a gaming machine, as only very few games feature such tricks that would not sound about right on the SwinSID.

However, there’s this downside with the SwinSID that it does not support analog controllers. This is because it’s the SID chip that handles the reading of analog controllers in the C64, and the A/D converters are not implemented in the SwinSID. The number of games supporting paddles, mice or analog joysticks is not that big, but still it’s a shame that they won’t work with SwinSID. Also the few games that support second joystick button are affected. They behave as if the second button would be triggered constantly.

So there is a lack of fully featured replacement for a SID chip. This is a shame as SID chips are sought after, and supply for good and working chips is getting more and more scarce. The demand of SID chips have been recognized, as it’s not that difficult to find a supply of SID chips from Asia. It’s just that many have found out that these chips are often dead, faulty or downright fakes, and often rebadged.

Knowing that there are a lot of these faulty SID chips with bad filters or missing sound channels, it had occurred to me that maybe these could be combined together with SwinSID to make at least a fully featured replacement for the SID chip. Sound from the SwinSID, and A/D converters from an otherwise faulty SID.

Recently I ordered some spare parts from Mutant Caterpillar Games, who have a selection of chips for 8-bit computers in stock, including SID chips. As we were talking together with Ian Gledhill about SID sourcing challenges among other things I mentioned this idea of mine. He kindly sent me few faulty rebadged SID chips to test it out.

So, off I am to build an adapter that allows me to install SwinSID and a ‘badSID’ to the C64.

Stuff from Retro-Donald

Just a quick heads-up, I recently ordered some stuff from Retro-Donald’s Sinchai-Shop. Finally the goods arrived, and above you can see the loot I got.

Top: Micromys V3. Below, from left to right: EasyFlash 3, MMC2IEC + programmed AVR, Nano SwinSID, Super PLA.

Sinchai.de is an online shop that is specializing in Commodore 8 bit accessories and DIY kits. Unfortunately the site is in German only, as is all communication and support. Additionally the information and instructions for the products may be very slight, and most of the product support seems to be at the German C64 forum Forum-64. The shop supports the community there and vice versa it appears.

At least the product assortment is very interesting, and they ship worldwide. And Google Translate is your friend if you are like me and don’t speak nor read German.

Apart from the language barrier and almost three weeks’ delivery time I’m very pleased with the experience. Might be that Donald is busy putting the now-released EasyFlash 3 boards together! The pieces I finally got are of good quality, and the packaging was well done. Postage rates were reasonable, and generally, so are the prices at the shop. My recommendations.

Quick run-down of the stuff I ordered

While I’m unboxing my own stuff…

It feels like it’s been ages since my last post. One reason for this feeling is probably the fact that I have moved during this break. Being more specific, I have moved in with my special lady. Who does her best to understand my interest to old computers and other weird stuff including my peculiar electro-analogish taste of music. Wish me luck ;)

Not starting a relationship blog here and still sticking to old computers and weird stuff; Some interesting SID related updates have emerged in the meantime for both SwinSID and 1541 Ultimate projects.

Micro SwinSID has got two firmware updates since my review. The updates have improved the ADSR envelope and filter emulation closer to real SID chip. The latest firmware also introduces 6581 filter emulation that can be selected by e.g. a switch by grounding one of the AVR pins. Unfortunately I haven’t had the change to get first hand impressions of the improvements as I’m lacking the means to program the microcontroller.

Micro SwinSID – an AVR based SID replacement

SIDs are sought after sound chips. Being semi-analog they are difficult to emulate. They also break easily from e.g. static discharges. If one is to build a SID synth or you need to replace broken SID chip you may have trouble finding the chips.

SwinSID is a project that I have been keeping an eye on for many years now. Swinkels, the man behind the project, has been prototyping and developing a SID compatible custom sound card for C64 or other SID-utilizing devices such as MIDIbox SID.

Originally the SwinSID was not aiming to emulate a real SID chip but rather to be a pin-compatible SID-like sound device with some enhancements. The hardware is based on one or two (stereo) Atmel AVR microcontollers and some additional circuitry including a DAC.

But now Swinkels and Crisp have developed a new model of a different goal. It is called SwinSID88, or Micro SwinSID, and it’s a direct replacement for the SID chip. It is mono only and it aims to emulate the sound of 8580 SID chip as good as possible.