Decoding Flux Information
#2
Each 16 bit value represents the flux duration/25ns. So, you take the value and multiply by 25 to get the total number of nanoseconds that each flux duration lasts. You have to also convert the drive speed to match the original recording speed during your conversion. That value gets converted into a 0 or 1 that is used for the FM encoding. You will notice that your values are either approximately 0x010A or 0x0085. These values are 8us and 4us. You are using a 360 RPM drive to read your disks. This is how you calculate it:

0x010A = 266
266 x 25 = 6650
6650 x 1.2 = 7980ns (7.98us)

1.2 is the value needed to convert a 360RPM value to a 300RPM value.

I know MFM and GCR quite well, but I don't really know much about FM, so you will need to figure out the encoding/decoding requirements.
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Messages In This Thread
Decoding Flux Information - by Relayer - 02-15-2016, 07:12 PM
RE: Decoding Flux Information - by admin - 02-15-2016, 09:10 PM
RE: Decoding Flux Information - by Relayer - 02-16-2016, 08:27 AM
RE: Decoding Flux Information - by admin - 02-16-2016, 10:30 AM
RE: Decoding Flux Information - by Relayer - 02-16-2016, 12:37 PM
RE: Decoding Flux Information - by admin - 02-16-2016, 02:49 PM
RE: Decoding Flux Information - by Relayer - 02-17-2016, 01:43 PM
RE: Decoding Flux Information - by admin - 02-18-2016, 08:43 AM



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