petSD+ - Firmware

Last Firmware Update : Get it here

The firmware for petSD+ is currently in development and a "production" version has not yet been formally released. During this development phase, firmware updates are available on Nils' "nightlies" firmware page. I will endeavor to keep the table below up to date as new versions are made available, but for the most up to date status and copies of the binary files, please visit the "nightlies" download page.

July 8th 2019 : IMPORTANT UPDATE ON NODISKEMU FIRMWARE STATUS

For the latest - see below

Nils has just advised me that he no longer intends to devote any time to petSD+ / NODISKEMU firmware updates. The 2018-10-28 firmware file will not be updated, whether or not any bugs or other problems come to light.

Unfortunately, I do think that there are some issues with the latest firmware (that may have been present for some time), but Nils has not been able to duplicate the problems that I have reported or figure out what the cause might be. I think that he is pretty skeptical that my findings are real but in any event, he will no longer devote any time to working on the firmware. To some extent, I can see why Nils does not believe me; the strange thing is that the problems only seem to manifest themselves with certain MCUs, but having built and tested many petSD+ units, I am 100% certain that there is a (admittedly, perhaps hard to find) firmware issue somewhere.

With Nils no longer willing to work on the code, it is likely that these firmware issues will go unresolved. Hopefully, your petSD+ does exactly what you expected it to, in that case, even if your firmware revision is older than the latest, unless you need some fix or feature in a later firmware revision, I strongly suggest that you DO NOT UPDATE THE FIRMWARE in your petSD+. You may find that a later firmware revision brings problems that you did not expect. If you do decide to update the firmware, take a note of the installed firmware version BEFORE upgrading, that way, you should be able to revert to a working system if the update causes issues.

Nils has licensed NODISKEMU as "Open Source" and his Github Repository hosts the source files for the current and all previously released versions of NODISKEMU. Unfortunately, I do not have the skills to pick up responsibility for maintaining the firmware, so unless some other PET enthusiast with AVR programming skills is prepared to take up the mantle, then NODISKEMU is effectively DEAD, or at least, has a status of "unmaintained".

WHAT NOW FOR petSD+ ?

It is a real shame that this situation has arisen, petSD+ is a truly great piece of hardware for the PET, there are many petSD+ users who should be grateful to Nils for his time and effort in developing petSD+ and for supporting it over the past 8 years or so. Other, cheaper, SD card based solutions are available, but the ability for petSD+ to coexist with legacy disk drives and transfer files between them over the IEEE-488 bus is a real differentiator - I am sure that the vast majority of petSD+ users would agree!

Whilst I want to continue to make petSD+ available, I am becoming increasingly frustrated by the extended testing time that I need to put in before I am happy to send out petSD+ and with the number of MCU "failures" that I am seeing - currently about 50% of the MCUs that I install have one or more issues that mean that I have been reluctant to ship them - I have accumulated a large number of costly MCUs that I am unable to use. (Anybody want to buy a "nearly new" ATMEGA1284p-PU?)

The most common "failure" is that petSD+ does not start up properly on power-on. There is a simple work around for this, but, until now, I have not knowingly sent out units with this "fault", however, I am considering moving to a position where, if I identify this "fault" during testing, and only with the agreement of the purchaser, I may not consider this as a failure and may ship the unit anyway. Having to do a manual reset on power-on is not ideal, but is a minor inconvenience that users may be prepared to live with if it allows them to get hold of a petSD+ that they might otherwise not be able to. This would only be for external petSD+ units as manual reset of an internal unit would be just too awkward.

This needs more thought though . . . . It may be that I offer a small discount for users willing to accept a petSD+ with this minor inconvenience.

Update 29/08/2019 - CURRENT STATUS

The last release of NODISKEMU firmware was dated 2018-08-28 but it continues to be problematic, with around 50% of MCUs not able to start-up the application code without the user needing to use the simple work around mentioned above. I have reached the point where I can no longer tolerate the 50% failure rate of MCUs failing to run this firmware revision "out of the box".