Progress at Didcot

Well done to everyone who has been involved in progress at Didcot over the last several months.

A great deal of time and effort has gone into soldering the thousands of connections to tags in the back of the panel – a seemingly never-ending fiddly task that made us glad we hadn’t tried to preserve anything bigger than Swindon!

The west of the panel is pretty comprehensively debugged and has been fully working (to the extent to which the software is programmed).

The east end is not fully debugged yet, as software progress is not as advanced on this end of the panel and it is more difficult to debug the hardware before the software performs reliably.

The volume of computer hardware in the panel has increased significantly over the last few months, with a computer required for each of the east end of the panel, west end of the panel, ‘outside world’ simulator, and train describer. Our collection of second-hand computers has been worked hard, and some patch-and-mend has been required in the short term. Once the final computer requirements are established we will install some decent hardware, but there is little point in doing this until the final requirements are known.

Integrating the hardware and the software has been challenging, especially as we are using the software for an installation far far bigger than anything envisaged when the software was designed (for model railways). Some hurdles have also been encountered because we have written our own code for the program in addition to using code written using the program interface, which has occasionally caught us out when newer versions of the program have been released by the makers.

The completion of the panel simulator is comparable to filling up a swimming pool – in that it fills up widely and slowly until one day it all reaches 100% full. We are at the stage of everything being 95% complete, and everything having been seem to work independently, and all the integration concepts having been proved, and it is now a case of ironing out all the snagging issues of making it all work together!

The original VDUs in the panel have been made to work (which was more tricky than it sounds!) and connected to the TD computer. This emulates the Vaughan Harmon train describer, which Swindon had for approximately its last 20 years. Previous to this there was an LED train describer and previous to that a Sodeco mechanical describer. We also have components available of both of these other types of describer, which we plan to recommission in the future on at least part of the panel.

The work is currently slow, sometimes frustrating, and doesn’t show such as visible progress as our earlier work, however, we will very soon complete this stage and move on to more detailed testing of the panel. Completion of the panel room ceiling is now imminent and very quickly the room will start to come together.

We hope, soon to be able to advertise some members’ days in the leadup to the grand opening in June.