P64
#20
Like I said, in the real world the LPF cutoff is lower than that, and you do in fact get pulses as low as just under 1us. It's easy enough to see using even a generic scope. Read a disk with the drive door open so invalid flux is generated. On disks themselves, flux transitions are as low as a few hundred nanoseconds, typically during the write splice. So, if you want to "preserve" and emulate the disk exactly, you would need to allow for the complete data. I doubt it matters much for C64 disks, but I want to be as exact as possible.

I am more than familiar with the 1541 schematic. Besides developing RAM boards, digital track displays, and parallel cable add ons, I first developed flux level copying in December of 1984 by replacing the write circuitry in a target drive and using the UE4's output for the source drive. So, 29 years later nothing has changed.
Reply


Messages In This Thread
P64 - by LordCrass - 12-30-2013, 10:31 AM
RE: P64 - by admin - 12-30-2013, 10:51 AM
RE: P64 - by LordCrass - 12-30-2013, 12:43 PM
RE: P64 - by admin - 12-30-2013, 12:51 PM
RE: P64 - by jupp - 12-30-2013, 04:55 PM
RE: P64 - by admin - 12-31-2013, 05:54 PM
RE: P64 - by BeRo - 12-31-2013, 07:07 PM
RE: P64 - by admin - 12-31-2013, 08:09 PM
RE: P64 - by LordCrass - 12-31-2013, 08:55 PM
RE: P64 - by BeRo - 12-31-2013, 09:05 PM
RE: P64 - by LordCrass - 12-31-2013, 07:41 PM
RE: P64 - by BeRo - 12-31-2013, 07:44 PM
RE: P64 - by admin - 12-31-2013, 08:43 PM
RE: P64 - by admin - 12-31-2013, 10:12 PM
RE: P64 - by BeRo - 12-31-2013, 11:54 PM
RE: P64 - by admin - 01-01-2014, 01:51 PM
RE: P64 - by BeRo - 01-01-2014, 10:36 PM
RE: P64 - by admin - 01-01-2014, 11:01 PM
RE: P64 - by BeRo - 01-02-2014, 05:06 AM
RE: P64 - by admin - 01-02-2014, 08:16 AM
RE: P64 - by LordCrass - 01-02-2014, 09:21 AM
RE: P64 - by admin - 01-02-2014, 12:49 PM
RE: P64 - by LordCrass - 01-02-2014, 03:57 PM
RE: P64 - by admin - 01-02-2014, 05:03 PM



Users browsing this thread: 1 Guest(s)