Virtual drives for the Commodore - noob question

[+hloberg]

I've noticed several different types of virtual drives for the Commodore line. are any kind better than others? Or all about the same?

 

[+hloberg]

Oh, I would like to maybe build one, I did that for my S-Drive for the Atari. Any suggestions along that?

 

[carlsson]

What do you mean with virtual drive? A memory card based storage solution?

 

SD2IEC / uIEC - Traditionally the cheapest ones, and exist in many different layouts from various vendors. These have in common that they simulate the logic structure of a floppy disk, meaning that software using stock Kernel routines to load and save usually work fine. These devices don't have computational power to fully emulate a 1541 though, so when it comes to fast loaders the device can detect about half a dozen popular routines like Epyx FastLoad, The Final Cartridge III, Action Replay (if one installs a 1581 ROM on the SD card), Dreamload, JiffyDOS. All other custom fast loaders which implement their own routines are bound to fail with SD2IEC, and since people expect to find all sorts of original, copy protected dumps of C64 floppy disks, many avoid this category of devices. Personally those have suited me fine for 10+ years though.

 

Pi1541 - A middle of the line solution, in particular if you have a spare Raspberry Pi 2 or better. You get a "hat" with the connectors and install software on the Pi that makes it emulate a 1541. In theory better compatibility than the SD2IEC devices. If you need to buy everything, this solution will not appear quite as affordable any longer. A little question mark for how well it works in practice and I think the original developer has shifted focus after too many capitalized on his design?

 

Ultimate-II+ (previously known as 1541 Ultimate series) - Top of the line. Quite expensive and at least earlier there used to be a long waiting list, not sure if supply meets demand today. Does everything you can ask for and more. Not only a memory card storage device, but also emulates cartridges, has a synthetic secondary SID chip, emulates RAM expansion and so on. For casual C64 usage it probably is gross overkill but if you're planning to get serious use of it, you might want to consider it. At least it is supposed to handle any image files you throw on it, fast loaders or not.

 

There have been a few more short lived devices inbetween those, like the UK1541 (Ultimate Killer) but I think it went out of production years ago. There is also the Turbo Chameleon 64 which is even more expensive than the Ultimate-II+ and might not even offer the same features but instead emulates the C64 entirely including VGA output. I know that is not what you're asking for, but just mentioning it here for completeness.

 

There also have been solutions using a PC for a virtual drive, good old 64HDD which used a DOS PC with parallel port. There even was a project to make a cycle exact 1541 emulation in the same way but back then the PC was too slow. In modern times I'm not sure if anyone has revisited this path, or if the memory card based ones are superior. There are of course various networked devices but that might fall outside your virtual drive scope.

[bluejay]

Seriously though, an SD2IEC is good enough. A 1541UII+ is worth it for its extra features I suppose, but if you're just looking for an SD based solution SD2IEC is perfect.

 

Maybe you might want to try the Pi1541 Zero though, a RPi Zero based Pi1541 which is small and cheap, or even 64hdd if you have the correct cable.

[+hloberg]

know of any SD2IEC kits? I like to add build projects to my project blog when possible:

 

[carlsson]

I know that the older MMC64 has been sold in kit form, not sure about fully compatible SD2IEC units. However Bluejay who posted just above you has made his own VIC-20 memory expansion with onboard SD2IEC so perhaps he has pointers to how you could make your own too. There may be schematics out there, and the firmware is freely available so it should be doable if you're into soldering.

[bluejay]

Ugh. I shoulda left the last of my VIC-20/SD2IEC units disassembled! I only assembled it a few hours ago.

 

I already got rid of all my gerber and design files because I had absolutely no intention of making any more of them, but maybe the PCB manufacturer still has it somewhere.

 

It'll be difficult to find an SD2IEC sold in kit form. They contain an AVR microcontroller and makes use of its flash and EEPROM, so you need to program that. And to complicate things further, most SD2IEC's use TQFP package microcontrollers, which are a complete pain in the rear to program.

 

If you're interested in a fully assembled one I do have one left to sell... Or you could design your own from scratch; it's not very difficult. If you do decide to go that route I can give you a few tips.

[carlsson]

Got rid of your design files? How large can those be? I mean in an era where hard drives are counted in terabytes it seems odd if you delete your files once you have had one product run and are unsure if you'll make another.

 

I bought my MMC64 kits from Retro Donald but he has closed his business many years ago. I don't know if you save many dollars on buying something in kit form, but perhaps you want to build it yourself as an exercise or because you're bored in your spare time.

[bluejay]

Eh, it really doesn't matter. It was a horrible design anyways; it was the first PCB I ever designed, so what do you expect. Besides, after experiencing the pain of assembling and trying to sell this stuff, I figured it wasn't something I would want to do ever again.

 

However, since there are barely any of these sold in kit form, plus the fact that there are next to no US based vendors that carry SD2IEC's (especially in cheap prices) designing his own is certainly a viable option. I could whip up a better design than what I original came up with in a few hours.

 

So, it completely depends on what he wants to do. He can do it the easy and boring way, or the hard but interesting way.

[carlsson]

Sorry to hear that your GET_RICH_QUICK scheme didn't work out exactly as intended. ?

[bluejay]

It couldn't have been a get rich quick scheme in the first place; I made too many mistakes and stuff. It's a miracle I only lost $70 from it. It woulda still been more expensive to buy the stuff I made from someone else.

 

Besides, I could've easily charged people $15 more than what I sold them for, considering what they normally sell for. The idea behind what I was trying to do was to provide an affordable solution who entered the retro computing world through the VIC-20 like I did. Although I failed on my little challenge to make it cheaper than the C2N datasette I bought for my VIC-20 back then, it was still an affordable solution for people who wanted a cheap all-in-one solution to everything they might need on the VIC-20 they just bought.

 

As long as you make no mistakes in designing the PCB and stuff, it's a fun experience overall. It's interesting to start with a pile of parts and watch them all combine into usable devices.

[desiv]

I like the Pi1541.  Helped I had a spare Pi0 already, and some level shifters and buttons in my arduino kits.

Works great...

And the GIT page shows an update from 8 days ago, so there is still activity there...

 

My only problem is I tried to get fancy and 3D print my own case (there are some for the standard Pi variants, but not the Pi0).

Like most projects, I got 85% or so done, and life paused the project.  And I am trying to get the energy to finish it up.

Need to make a small board to hold the buttons and finish modifying the case design to hold my button board.  (I think I have the case designed to hold the screen).

Right now the buttons and screen are just plugged into a breadboard.  ?

 

I think the only drawback of the Pi1541 is that it needs it's own power.  Not a huge deal (the 1541 also needed it's own power), but the SD2IEC has it beat there.

 

Note:  You don't have to use buttons and a screen with the Pi1541.  You can just use the filebrowser in the C64/Vic.  But I like buttons and screens.

[bluejay]

@desiv The SD2IEC also needs power as the IEC port provides none. It's just that most of them come with cables to connect the thing to the cassette port and the Pi1541 doesn't. Theoretically you could wire a USB connector to the cassette port to power your Pi1541 but I'm not sure if the power supply of the computer could handle it.

[carlsson]

No!!!! The 5V pin on the user port, and I suppose the cassette port, is recommended a maximum draw around 100 mA. Perhaps you can strain it a bit more, but nowhere near the power requirements even a Pi Zero (and the Pi1541 hat) draws. You really need a separate power supply for that solution to work safely. Perhaps if you have a heavy duty power supply for the computer, you could splice the 5V line into a wire that goes to the Pi but the older (fault prone) supplies usually are rated at 1.5A. I know that some people have developed replacement PCBs for the old power supply (instead of replacing it entirely) that would let you draw 2.5-3A from the same transformer but it is another matter.

[bluejay]

I did some googling; max draw of ALL the ports COMBINED is 100mA. So yeah, I guess Pi1541 powered by the computer is a nono.

 

Edit: Pi1541 Zero consumes 80mA. So I suppose if you are using a Pi1541 Zero it might be possible to wire it to the cassette or user port.

Edited February 1, 2021 by bluejay

[carlsson]

Does the hat consume anything, if you use one without LED display? It might work but it sounds dangerously close to recommended max, on behalf of the practicality of not having to use one more power supply and cables going across the table.

[bluejay]

9 hours ago, carlsson said:

Does the hat consume anything, if you use one without LED display? It might work but it sounds dangerously close to recommended max, on behalf of the practicality of not having to use one more power supply and cables going across the table.

I suppose it would but I don't think it would consume a lot more than 20mA. But yeah, no point in risking damages to the power supply/computer when you can just use a proper power supply.

[desiv]

13 hours ago, bluejay said:

I did some googling; max draw of ALL the ports COMBINED is 100mA. So yeah, I guess Pi1541 powered by the computer is a nono.

 

Edit: Pi1541 Zero consumes 80mA. So I suppose if you are using a Pi1541 Zero it might be possible to wire it to the cassette or user port.

I've seen the 80mA listed, but I've also seen higher draws listed as well.

https://raspi.tv/2017/how-much-power-does-pi-zero-w-use

 

Not sure how hard Pi1541 drives the Pi0, but if it's on the higher end, it might be problematic...

[robbievgb]

I was looking for this exact same information as I want to get my dad setup with one of my spare C64s, a decent svideo upscaler (probably a budget RetroTink) and a bunch of software. However I have another question:

 

How user friendly is using the SD2IEC? Is it as simple as dumping images on a SD card? My dad is not super technical when it comes to newer tech. 

Edited February 12, 2021 by robbievgb

[bluejay]

@robbievgb It functions exactly like an actual drive, except the SD card is the floppy drive. You can do whatever you can do with a real floppy drive except using a FAT32 SD card. I recommend you check the following link regarding the use of an SD2IEC.

https://www.thegeekpub.com/9473/sd2iec-manual-use-sd2iec-c64/

[carlsson]

Yes, there are file browsers like FB64 mentioned on the linked page. That will simplify usage beyond what it was like using real floppies back in the day. A fastloader cartridge like the Epyx Fastload clone pictured (or any of the other handful cartridges supported by the firmware, see my post above) is highly recommended.

Edited February 12, 2021 by carlsson

[bluejay]

Technically you could use a File Browser with a real floppy drive. You'll need a disk with a higher capacity of course (such as a double sided 1571 disk or the 3.5" 1581 disk) to store the d64 images, but it's possible. That's why I like to think it's pretty much just like the real floppy drives in function.