Why no PET IEEE-488 -> IEC Hardware?

[WimWalther]

Seems like a fairly obvious question.. Why isn't there any hardware that supports connecting one or two CBM 1541 drives to a PET, like a standard CBM dual floppy?

I realize that the dual drives are configured as a single device number, with two LUNs for the drives (0 & 1), but this really shouldn't be an issue.

The disk track & sector formats / directory structure are also very similar, yes?

What prevents this from working?

 

[Hutch]

There are a couple of options I've seen for this.

One is Sven Petersen's CBM 1541 Adapter, which lets you connect a 1541 to a PET via the User port, not the IEEE port. As such it requires an option ROM for the IO code.
Link: http://tech.guitarsite.de/cbm_1541_ada.html

Another is the 1541 to 2031LP conversion, which mods a 1541 to connect via IEEE.
Link: http://blog.tynemouthsoftware.co.uk/2016/08/commodore-1541-disk-drive-to-2031.html

And another is Stéphane Ghenne's "OneBus" which converts from IEC to IEEE or IEEE to IEC and allows connection to virtual network devices.
YouTube Video Link

 

[Hutch]

 

[erd]

One is Sven Petersen's CBM 1541 Adapter, which lets you connect a 1541 to a PET via the User port, not the IEEE port. As such it requires an option ROM for the IO code.
Link: http://tech.guitarsite.de/cbm_1541_ada.html

I built one of Sven's adapters and brought it with me to VCF East. It works great, but as mentioned, it requires add-on firmware, and that firmware depends on the BASIC 4.0 kernel. I think it also requires a few bytes of RAM at the top of the 80-col 2K video space so if you wanted to use this with a 4032, you would have to add a couple of 2114s and probably the other chips in the 8032 video circuit. I only have one 4016 so I haven't tested that.