Toronto PET User Group YouTube Channel

The Toronto PET User’s Group (TPUG) has placed a number of 2009 and 2011 World of Commodore (WoC) presentations online at  Yours truly is in some of the 2011 ones, discussing EasyFlash 3 and ZoomFloppy.  I guess, now that presentations will be online forever, I’ll have to do a better job or presenting and ensuring all information is accurate (I think there’s a few inaccuracies in my WoC presentations).  In any event, if you’ve never met me, check out the videos and realize you’re not missing much :-).

New Store Items

We’ve added some additional items in the store for both hobbyists and users:

IEEE 488 Cable
IEEE 488 Cable

We now have 3′ (36″, nearly 1meter) IEEE 488 cables in stock.  They are heavy duty shielded cables with “passthrough” IEEE connectors on each end

DB-15 Parallel Cable
DB-15 Parallel Cable

We also now stock 6′ (~2M) DB15-F to DB15-F cables that can be used for parallel drive access with products like ZoomFloppy.


On the connector front, we’re added VIC-20 expansion port connectors, cassette port connectors, and C64/C128 expansion port connectors to the store.

To fill out our EPROM offerings, we’re happy to announce we’ve found a nice supply of new 27C64 and 27C256 EPROMs in addition to replenishing our stock of 27C020s.

ZoomFloppy Tape Support

Arnd Menge has delivered the first set of patches allowing ZoomFloppy to interface with 1530/1531 tape hardware.  In the coming days, Arnd hopes to complete development of this new feature, and I am looking into creating a daughtercard that will attach to the ZoomFloppy via the X5 expansion connector.

Obviously, such support is alpha at present, but the device is proving very versatile with the recent improvements!

Arnd Menge

ZoomFloppy SRQ Nibbling Support

During ZoomFloppy development, Nate Lawson tested and found that the 1571 drive, with it’s faster clock speed and hardware shift register data transfer support, could potentially support serial data nibbling.  Current nibbling options require a cumbersome and difficult-to-install parallel cable.  As attention was placed elsewhere, the idea was shelved pending initial implementation code.

A while back, Arnd Menge submitted a patch to enable serial nibbling using the ZoomFloppy hardware and the 1571 SRQ line.  Continued testing and refinement of the patch goes well.  Thanks go out to Arnd for the patch and bug fixes, and to Nate Lawson for debugging this new functionality.  Currently, only reads are supported, but write support will be added once the basic concept and initial implementation is proven.

When complete and added to the base firmware and OpenCBM libraries and tools, C128DCR 1571CR owners, who previously were unable to utilize their drive for data nibbling (lack of parallel port option) can utilize this solution to quickly read data from the 1571 drive unit.

We’ll continue to monitor the progress of this new feature.  Though the solution is close at hand, software support for this new feature might take longer.


ZoomFloppy IEEE-488 Support

Thanks to the hard work of Thomas Winkler, ZoomFloppy now supports Commodore IEEE-488 devices.  Many thanks also to Nate Lawson for incorporating Thomas’ changes into the ZoomFloppy base firmware image.

Existing units require a firmware update and the population of the IEEE-488 connector fr operation.  As there is not a simple firmware update utility at present, users may wish to wait until an official upgrade solution is available.  However, users who wish to download some programming SW and follow a step by step tutorial can upgrade immediately (disclaimer:  RETRO Innovations takes no responsibility for upgrade issues, though there is no way to completely brick the unit.  At worst, RETRO Innovations can reprogram the unit and ship back to the customer).  All newly ordered units will contain the updated firmware.

IEEE-488 Connector Supplies

IEEE-488 24 pin Centronics Connector
IEEE-488 24 pin Centronics Connector

As some may know, IEEE-488 is no longer a preferred global interface standard.  I would even go so far as to state it was niche even in its heyday.  HP used it as the “Hewlett Packard Interface Bus”, and it was also known as the “General Purpose Interface Bus” (GPIB), as I recall.  Still, more names do not increase a standard’s usage.

Now, 30+ years later, it’s becoming quite difficult to find economical sources for IEEE-488 parts. I surmised cables would be expensive, given the number of wires in IEEE-488 cables and the pass through connectors present on many of them. However, I was surprised at the expense for the Centronics 24 pin connector used in the standard. Though 36 pin Centronics (parallel port) connectors are nominal in price, I initially found but a single source offering the 24 pin connectors.  Of course, that source offers them for $9.00 a piece.

Recently, I’ve found a more economical source, one that can supply not only the connector, but also the special studs that the standard requires.  Though the minimum order is 1000 units, I feel there’s enough demand to justify a bulk purchase.  The ZoomFloppy hardware supports the connector already, and future devices should support IEEE-488 as well.  Thus, I’ve ordered 1000 connectors, and will add them to the store at the reduced price one they arrive.