Tape routines: mess in SLOW mode

[iss]

Does that mean it should be rather early when the signal goes "up again"? (knowing that, like Dbug said, it could depend on each machine). That would be fine with the example where I wondered where it began: it seems the earlier it is, the closer to the writing it is.

Yes, there are differences on each machine.
But because VIA's CB1 (input) is set to detect the rising edge only and each bit length is measured as time between 2 rising edges, for me the differences theoretically should be minimal i.e. for both standard protocols (fast & slow) it doesn't matter actually at what voltage the rising edge will be detected.

[Symoon]

Ok here's the beginning of the explanation why Euphoric gave "Errors Found".
See the picture: this is the end of the 1st $16 byte of the signal generated by Euphoric, in two different cases.

The upper one begins as expected (see the transition from the two-samples long "1" value with the 4 samples long "0" value), the lower one is reversed. As you can see, if you measure the lentgh between two rising edges, the upper one has 17 "0" values (more than two samples), while the lower one has 16!
(don't ask me why/how Euphoric or the Oric started once in a way, and the other differently, maybe I had made several CSAVE in a raw).

The upper one gives "Errors Found", not the lower one. Note that with the half-bit bug, next bytes signal will be reversed, and so on. Now I will check later exactly why it does that with the ROM code, because for the moment I'm in a rush with all my Oric stock at hand, doing 4594535678 things and leaving back to Paris within a few hours

EDIT: maybe the expected one is the lower, I'm a bit tired and mixing things right now.