1541 – Why so complicated

The Commodore 64 has a disk drive that is unique in many ways. Not only is the Commodore 1541 said to be the world’s slowest disk drive, but it’s also big, bulky, noisy and has a reputation of being unreliable. Also, it works in an unusual way. In many ways it’s the disk drive that has defined our experience with the C64.

In addition to the original model 1541 there were also the updated models 1541C and 1541-II from Commodore. The drives have different looks, differences in hardware and in ROM versions, but the basic functionality and features are principally identical.

Some later models in Commodore’s 8-bit serial disk drive range were improved in some ways, but those have less importance today. For a C64 as a retro system, the 1541 is the de facto standard. Still, in this time of emulators and hardware add-ons, compatibility with the original 1541 disk drive is regarded as a must.

And today, for someone who doesn’t want to resort to emulators only, the large and unconventional disk drive brings some practical challenges. So understanding the 1541 helps us to understand the options we have for replacing it!

MMC2IEC, a uIEC alternative

Already good while ago I bought this MMC2IEC kit from Retro-Donald together with other junk. Basically it is just one hardware design variant that runs the popular and widely used sd2iec firmware. Just like the uIEC, SD2IEC, C64SD and many other devices. If you randomly come by an SD card drive for 8-bit Commodores, it’s probably some sort of SD2IEC/MMC2IEC variant.

This particular variant of the hardware goes by name Peter Sieg Platine, Peter Sieg plate. It’s Lars P. hardware configuration – which is important information when flashing or updating the AVR firmware. The kit came with ATMega 1284 AVR – a 128k chip that is likely to fit also the upcoming updates of sd2iec firmware in future.

Anyhow, this one was not a complete ready to use device, but a DIY kit that consists of nothing but the board, the SD card slot and an optional preprogrammed AVR chip. The kit with programmed AVR didn’t cost very much, and the remaining electric components were only few euros from a local electrics shop.

Even though this kit is no longer available from Retro-Donald’s Sinchai shop, I’ll go ahead and run down what I did with mine and how I built it. After all, this device is so simple, that it would be fairly easy to build one without any kit. If you have the possibility to make the PCB and program the AVR, plus solder all the parts together, you can basically make this very device from scratch.

The PCB design and layout files are also available in different formats here and on the author’s page.

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

EasyFlash fastloader comparison

Unseen has finally released a new version of the sd2iec firmware. This new firmware version of 0.10.2 does not bring that many updates, but one that I have been waiting for; sd2iec has now support for the fastloader that has been in EasyProg since ages.

I wanted to make a little comparison of the now supported fastloader’s performance using uIEC. Which is faster, EasyProg fastloader or JiffyDOS? Will it take even less time to flash the cartridge if the cartridge image is compressed using EasySplit?

Hardware & software configuration:

• C64E (new, short board) with JiffyDOS KERNAL, switchable between standard KERNAL and JiffyDOS 6.01
• uIEC/SD v3.1 with sd2iec firmware 0.10.2
• Standard EasyFlash cartridge
• EasyProg 1.5.2
• EasySplit 1.0.0

The image I flashed several times using different configurations was Prince of Persia C64 version 1.1. It is a 513 kb cartridge image, closely half of the flash memory size of EasyFlash. When the image is compressed using EasySplit, the file size is 159 kb. In Commodore terms, the images were 2069 and 644 blocks respectively.

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.

Tips for using sd2iec

It’s been already a while since I got the uIEC – one of the available hardware running the sd2iec firmware. I did some experimenting with it on how to make the best use of it if the nicely accompanying JiffyDOS is not present. I posted my experiences at Lemon64 forums, but I thought it would be nice to share them here as well. Still, you might want to read that instead for shorter, less detailed description.

Note that I’m describing sd2iec-firmware being used on uIEC/SD-hardware with Commodore 64. Many different hardware combinations are possible.

The principle

With sd2iec loading files from the SD card’s root folder is like loading files from a floppy disk. The very basic loading procedure is exactly the same – except that the default device number is not 8 but 10. So LOAD”$”,10 or LOAD”GAME”,10,1 works just like one would expect.

Things get more complicated if you want anything more. Something like to enter a directory on the SD card or to mount a .d64 disk image. A real Commodore disk drive wasn’t designed for such things so you don’t even have the commands for something like that. Since uIEC is connected only to the serial port of C64 it can be interfaced only using the IEC bus. Enter the command channel! Everything like directory navigation, disk image mounting and device configuration is done by sending drive commands over the command channel.

New hardware for C64: uIEC

Few days ago I got myself a uIEC/SD ordered from Jim Brain. I also bought a set of JiffyDOSes which should make a perfect match with uIEC. Even though I am a happy 1541 Ultimate user I wanted to get familiar with this device as it and other SD memory card applications using the same sd2iec firmware seems to be very popular. Also, this one can be nicely used in Commodore machines where the C64 Expansion port is not available.