C64 A/V cable – theory and practice

A while ago I made a proper SCART cable for Amiga, so why not for C64 as well? So what I did was a C64 SCART cable with selectable composite/S-Video mode, including a ‘chroma fix’ and audio noise reduction ‘mod’ plus a preparation for possible stereo audio use. But let’s start with the theory.

Cable making principle

Building an A/V cable for C64 is not very difficult. In the simplest form, what is needed are plug for the C64 Video port, a cable with enough wires for the desired operation and the output connector(s).

C64 Video port

The C64 Video port is an 8-pin DIN connector, which is a standard multi purpose connector. It means that the required DIN plugs are easy to find and cheap. However, there are two different versions of the 8-pin DIN plug. The two versions differ in the shape of the arc that the pins form. Best shown as a picture:

The two pins marked in grey in the wrong type DIN plug will prevent the plug from being inserted into C64 A/V jack. But not to worry in case you’re holding a wrong type plug in your hand, these two pins can be cut off or pulled out. In any ordinary A/V cable they are not needed anyway. Here is the Video port pinout:

Some early C64′s had 5-pin Video port that are missing the pins 6-8. It means there’s not separate chroma signal available there.

Make note on the pin 8. It is either directly wired to the +5V DC line from the PSU (after the power switch) or not connected. According to my first hand research, the +5V DC line is present in the C64′s Video port in all but the earliest two models. The +5V line is present starting from model C64B, or motherboard ASSY-NO. 250425. That means machines manufactured starting from 1984.

EasyFlash 3 hands-on

At the end of last year skoe released the EasyFlash 3 design. Just like the original EasyFlash, the design is open source, so basically anyone is able to start making those. It’s likely that these boards start surfacing from different sources. The first place selling assembled EasyFlash 3 cartridges I found was Retro-Donald’s Sinchai-Shop, and mine’s from there.

There are already at least two board designs. One like mine here, a short cartridge with buttons on both sides. The other design has longer board and the buttons are at the back in the usual way.

You North-American folks are probably pleased to know that RETRO Innovations is going to manufacture and sell them as well.

And yes – this is your JiffyDOS on a stick .. err.. cart solution!

Seriously, calling EasyFlash 3 just that is a vile devaluation (and I’ve seen it already happen). It’s much more than “just” a KERNAL on a cartridge.

The beauty of simplicity

You know the classic Suncom’s Totally Accurate Controller MK2, right? The favourite Atari-standard joystick of countless people, with the reputation of being indestructible. Other than durable, it’s also a very good game controller. The design is simple, you can hold it in your hand very comfortably, no matter if you’re left or right-handed. And the feel and tactile response is top-notch.

While not completely fail-proof, at least TAC-2 withstood abuse much better than most other joysticks that were commonly used with Commodore 8-bits, Amigas and Atari computers.  Both the durability and usability are result of very, very simple yet functional design.

I mean, have you ever looked inside of that controller? It appears that there isn’t anything that could ever fail.

Here’s a picture of TAC-2 dismantled. You can completely take the stick apart and put it back together without using any other tools than a screwdriver, which is needed for the three screws that hold the case together.

The buttons and directional switches are nothing but robust construction where metal part presses against another when you press a button or the stick into some direction. In its simplicity it’s ingenious.

But in fact there are some common issues with TAC-2. The buttons tend to become unresponsive over time. As with any switch, metal oxidation is the reason. Or plain dirt. Eventually this may happen with the directional stick too. But in fact, you could try to rub the contact surfaces cleaner without even opening up the controller. Just wiggle the stick around or rotate the button with your thumb while pressing it. You know you used to do that!

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

Reviving old C64-tower project

This is my C64 tower. It has been built nearly 12 years ago by me and a friend of mine. It has seen it’s best days long time ago, but now I’m about to make it better than it ever was.

Built into the old IBM case is a C64E motherboard (the new, short board) from a late C64 C and a much older 1541 disk drive. Basically the machine is an original hardware setup – including the original power supplies. The C64 motherboard is mounted horizontally at he bottom of the case. The C64 PSU is attached to the flank of the case – not very discreet I know. The drive mechanics of the bulky 1541 drive fit perfectly to one of the 5 1/4″ drive bays. The motherboard (or logic board) and transformer have been relocated around the mechanics.

An external power cord plugs into the rear of the machine. The mains voltage is routed to the original transformers trough a two-stage switch and fuses. The two stage switch makes it possible to power the C64 without starting up the disk drive and also to switch off the 1541 while C64 remains on.

The obvious issue of keyboard was also solved in a rather straightforward manner. The keyboard ribbon was simply cut, and then wired to the PC’s serial port connector at the back of the machine. An extension cable for the keyboard was done from old printer cable, which then plugs into the port. Not pretty but does its job!

The other necessary connectors were also routed to the back of the machine. A composite video, dual mono audio and RF antenna connections were routed to the added back plate of the machine using RCA plugs. The transparent back plate is in place of the missing PC PSU. Joystick ports are available at the bottom, as the motherboard barely fits inside the case.

The C64 and 1541 use the case’s power and HDD LEDs as their power LEDs. The power button of the case acts as a reset button for the C64.

Stereo to C64 with DualSID

I finally assembled one of my DualSID kits. It’s an add-on board for C64 that makes it possible to install an additional SID chip with several different configurations. Detailed description can be found at the DualSID home page or in my earlier post.

I made this one as the 8580 version. Here’s the board – without and with SID chips.

For the convinience of installing it from one C64 to another if needed, I made all external connections and jumper settings using pin headers. When the board is like this, the second SID address selection is done by setting the jumper block in the 2×4 pin header to correct position. Instead of manually changing the jumper block’s position, I’m able to replace the block with 2×4 female pin header that is wired to e.g. a rotary swithch. That way the changing of second SID address can be done externally.

New life of EasyFlash as a cartridge format standard

Since my hands-on review of EasyFlash cartridge things have been moving forward. EasyFlash has been gaining popularity in the Commodore community.

At the time of my overview there were only few EasyFlash tailored releases around, and I thought that the most prominent use of EasyFlash cartridge was the possibility to create EasyFlash multicart images from several single load programs using the Draco Cart Maker.

Since that, the EasyFlash tailored game releases kept on coming. These are usually some of the bigger games for C64, or even compilations of them, modified to run from EasyFlash without loading pauses, often including extra graphics, documents or other bonuses, incorporating bug fixes to the originals, and often with game or score saving feature writing directly to the flash memory. These features are sometimes found only in the EasyFlash patched versions.

At the moment there are quite a few EF releases already, and I’m sure new ones keep on appearing. Basically EasyFlash has become a new medium standard for C64.

And even more so with the phenomenal C64 port of Prince of Persia by Mr. SID. It’s a 1:1 port of the original Apple II game and graphically almost on par with the PC and Amiga versions. The famous fluid animation is there and the gameplay is identical to the original game. Not to mention it’s a great game and a classic, now for the first time ever available on C64 and C128. And it’s available only for the EasyFlash cartridge.

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.

New C64 hardware rolls out

New hardware just keeps on coming for the C64. Now, a new device called Alien Flash Cartridge and the long-awaited Chameleon cartridge are available.

The Alien Flash Cartridge was revealed at Lemon 64 Forums only two weeks ago. It is 16 megabyte Flash memory cartridge that has EasyFlash support and Action Replay compatibility. It also features USB connection that can be used for flashing the cartridge and also to download programs directly to C64 memory. Basically the cartridge has 16 one megabyte memory banks and each of them act like EasyFlash cartridge – except those can be flashed over USB connection. This alone is awesome, plus add the Action Replay mode and the ability to push single load programs to C64′s memory over the USB connection. Certainly a very interesting piece of kit!

If this sounds like must thing to have better act fast. These cartridges can be preordered now and the preordering is open only until 6th March! The developer Stingray sells the cartridges over at his website Multimeter Calibrations Australia. Check the link to Lemon discussion for more info. Find also the few demonstrative YouTube videos.

If I didn’t have EasyFlash and several Action Replay compatible devices already I would be placing order right now!

The Chameleon, in turn, has been in development for a long time. It started out as a “VGA box for C64″ but bloated out to become something much greater.

Since the C64 does not provide any higher spec video signal than S-video, the starting point idea for Chameleon was to replicate the VIC-II video chip using a powerful FPGA core and have it generate the VGA video signal to have high quality picture for today’s monitors and televisions. Since there’s some serious processing power available, why not use it also for something else? Well, they did.

C64 EasyFlash

New hardware for the C64 appears like it was still a production machine. It’s amazing. This time I’m talking about EasyFlash cartridge. EasyFlash has existed for some time already, and now I got myself one of those.

I bought mine fully assembled from Mike Betz via Lemon64 Forums. These carts are nicely finished with quality case, stickers and all. And of course I peeked inside – the case hides the real quality of the cartridge; Professionally made PCB, all socketed chips and flawless soldering make up these EasyFlash cartridges.

So what’s EasyFlash?

EasyFlash is a Flash memory based programmable cartridge for C64. Basically it works like any original game or software cartridge except that the cartridge binary (data, or cartridge image) can be easily erased and rewritten. And this is done using no other tools than the C64 and software called EasyProg. Any standard (8k & 16k) or Ocean Type 1 (128k & 256k) cartridge image can be written into EasyFlash and it effectively “becomes” that cartridge.