Greaseweazle

[Chuck Guzis]

On 2/3/21 9:36 AM, Mattis Lind wrote:

> So you store a full track worth of data and then write it to the
> SD-card. Then move the flux-length data over to a PC and do post
> processing there, right?
> 
> Isn't there performance in the CPU to do the actual decoding as well?
> FM, MFM, GCR or whatever into data. Find marks, check CRC and all that
> stuff?

Sure, more than enough.  But the MCU has to be programmed to do these
things; when dealing with an unfamiliar or problematical sample, it's
easier to move the data to the Big Machine and play with things
there--and there's a "permanent record" of the sampling data.

Were I dealing with lots of known samples, I'd probably include the
deciphering routines.  But in the end, the recovered data has to go back
to the customer, so it's going to wind up on the Big Machine anyway.

I incorporate a function on the MCU that attempts to find the "peaks" in
the spectral information, just as a way to tell if I'm doing things
right.  Same for verifying the drive spindle RPM.

--Chuck