On CDTV Version Numbers

There is a recurring mistake I’ve regularly observed when people discuss CDTV OS ROM versions online, and I have observed it often enough over the years to start mentally logging it. And because I derive deep satisfaction from telling people on the internet they are wrong about something, I decided this series is the perfect place to do just that.

The mistake is this: treating the version string as a decimal number. It is not a decimal number. It has never been a decimal number. And yet, consistently, reliably, someone will look at v2.7 and v2.30 and conclude that v2.7 is the newer build, because 2.7 is greater than 2.3. Mathematically impeccable. Factually incorrect.

The period in a Commodore version string for the CDTV OS ROMs is a separator, not a decimal point. It separates the version number from the revision number. v2.30 means version 2, revision 30. v2.7 means version 2, revision 7. The number 7 is less than the number 30. v2.7 is the older build. Once you know this, it is not complicated, but it is also not obvious at a glance, and that is presumably why the confusion keeps happening.

 

Commodore Versioning

Commodore typically used a two-component version string across all of their software: version and revision, separated by a period. The version number tracks major releases. The revision number tracks incremental updates (sometimes even individual builds) within that version. Neither component is a fraction. Both are plain integers. The string “2.30” contains the number two and the number thirty. Full stop.

This same scheme applied to the Amiga operating system, which is where some context helps. The Kickstart ROM had internal version strings like 34.5, 37.175, or 40.63, i.e. version 34 revision 5, version 37 revision 175, version 40 revision 63. If you ever poked around in the About screen on a real Amiga or dug into any Amiga documentation, you have already encountered this numbering scheme, even if you did not consciously register it at the time.

To further complicate matters for the uninitiated: Amiga OS ran two naming schemes in parallel. On top of the internal version strings, Commodore also maintained a public-facing marketing scheme. Kickstart 1.3, Workbench 2.0, Kickstart 3.1 are the product names most people know, the ones that appeared on the box and in advertising. They each map to a specific internal version string. (Kickstart 1.3 is internal version 34.5, since you asked.) One scheme for the engineers, one for the customers.

 

No Marketing Names

And here is where CDTV OS becomes its own particular headache: there are no marketing version names for it. Commodore never gave CDTV OS a shelf-friendly product name the way they did for Amiga OS. To be fair, Commodore also never gave CDTV a particularly shelf-friendly shelf presence, so perhaps this is consistent. The most likely reason for this is because they wanted to avoid the association of “computery-sounding” version numbers with a living room appliance. If you bought a CD player or VCR in the 1990s, you weren’t typically interested in the version number of the internal firmware of the device either. So, there are no public facing, marketing version numbers for the CDTV OS. There is only the internal version string. Which means the only tools available for identifying and discussing CDTV ROM versions are the raw numbers.

The next time you see someone confidently declare that v2.7 is the newer build (on a forum, in a comment section, at a dinner table, wherever life takes you) you can correct them, link them here, and go to bed knowing you made the world a marginally more accurate place. You are welcome. ■

See you on the next track!
— Captain Future