After inspecting some material provided by Pawel, I tested some experimental functionality in TAPClean that can automatically adjust pulse durations used to read/decode data within a TAP file.
The idea is quite simple: usually pilot sequences seem to be quite good to predict how much pulse durations written to tape diverge from ideal values, possibly because they are not subject to data-fetching delays at mastering time. This is not a novel approach as the CBM ROM Loader itself adjusts timings within read routines based on the 10 second pilot tone alone, in order to compensate for variations in motor speed for different tape drives.
Tests show that recognition of a Turbotape 250 compilation can be improved significantly using the above approach, with the elimination of read errors caused by non-ideal pulse durations. I haven’t thought of a way to fully integrate the code for the generic case as it can get tricky to add this feature for every loader supported in TAPClean, unless I change all scanners in one go, which is a bit of a risky approach.
Stay tuned for more on this!
In order to share comprehensive documentation about the tape loaders I’ve studied so far, including their disassembled and commented code, I decided to start with publishing the details I gathered about the “Mega-save” utility submitted to my attention by Paul Jones.
Paul should be given full credit for having identified the “Mega-save” utility as the mastering tool used to record tapes whose loader was previously referred to as “CHR Loader”. I can’t stress out how important this discovery was in order to reconstruct the history behind this specific loader. A few similar discoveries were made by Paul, and I am sure a few more are yet to be made, so keep up the good work, Paul and all!
That said, the encoding format created by the tool known as “Mega-Save” is documented here.
Bear in mind I am just starting with this effort and therefore I realize it might take a few iterations to get the documentation in perfect shape 🙂
In the last couple of days I’ve done some work and testing on my multi-threaded C2NEmu GUI client so I am happy to share binaries for Windows and Linux here.
After work today I started the development of the multi-threaded GUI client for my C2N Emulator device.
I also did some initial testing this evening and I reckon I will be testing some more before releasing binaries officially.