On 10 May 2009 at 23:21, Andrew Lynch wrote: By "extensions" what do you mean, Andrew? Will it archive Victor 9000 diskettes? --Chuck -----REPLY----- Hi Chuck! Thanks! By extensions, I mean the Disk IO has a regular Shugart mini-disk interface with all the usual signals and options. It also has the "feature" interface which imports/exports the rest of the NEC765/i8272 signals necessary for 8" and other drive support. An 8" drive cable with what signals are needed for that drive could be fabricated using the Shugart mini-disk interface plus whatever signals/options are needed from the feature connector. The 8" drive cable would be custom to Disk IO and that drive but there are multiple 8" drive interfaces so that seemed to me to be the most flexible way to provide support in a limited PCB space format. Please check out the Disk IO schematic on the N8VEM wiki for illustration of what I mean. http://n8vem-sbc.pbworks.com/browse/#view=ViewFolder&param=Disk%2520IO The Disk IO also brings to the feature connector intermediate signals for external processing like RAWREAD, /INDEX, the decoded FM/MFM stream from the FDC9229, etc. It also has VCC and GND for easy extension into "smart cables" to allow external processing of the intermediate signals. A uC or PC interface could tap off the RAWREAD and /INDEX signals and decode the disk directly or use the FDC9229 data separator to decode FM/MFM data. I think hard sector disks could be supported using this technique and even more exotic formats such as M2FM, etc. I don't know if the N8VEM SBC + Disk IO board could decode a Victor 9000 disk as I don't know anything about the format. However, with the Shugart mini-disk interface and the feature connector by themselves it may be possible. It's very likely (IMO) by using the intermediate signals fed to an external uC or PC for high speed sampling/decoding using the Z80/i8272 as a mode controller. I am not suggesting the plain 4MHz or 8MHz Z80 has enough bandwidth to decode raw read disk flux transitions like a Catweasel does. What I am suggesting is if someone were interested in pursuing such a serial port based floppy disk archiving project is to use the N8VEM SBC and Disk IO as a starting point since much of the work has already been done. Starting over from scratch would add a lot of unnecessary work and probably some marginal benefit when done, if it lasts that long. Using the N8VEM SBC and Disk IO board the project could launch in days or weeks rather than months with a "clean sheet" design. If the really exotic stuff were desired which required a uC or PC interface that could still leverage the existing N8VEM design as infrastructure and focus on just the disk sampler/decoder using signals and power supplied from the Disk IO board. I hope this helps! Thanks and have a nice day! Andrew Lynch