[cctalk] Re: 50 Years of the HP 3000

2022-11-03 Thread Chris Hanson via cctalk
On Nov 1, 2022, at 11:55 AM, Mark Moulding via cctalk wrote: > > I'd like to see $2000, but will cheerfully entertain offers (cheerfully if > they're reasonable, or met with hysterical laughter if not). You may need to adjust your expectations on that front. Even with pandemic-related

[cctalk] Re: Disk imaging n00b

2022-11-03 Thread Fred Cisin via cctalk
On Thu, 3 Nov 2022, Sellam Abraham via cctalk wrote: Fred, The Victor/Sirius 9000 was sort of PC compatible and featured a varial speed floppy format, no? Although MS-DOS capable, the Victor/Sirius 9000 was FAR from PC compatible! An amazing machine, but NOT PC compatible. It is an ideal

[cctalk] Re: Disk imaging n00b

2022-11-03 Thread Fred Cisin via cctalk
> Is Constant Linear vs Angular Velocity (?) anything I need to worry > about when sticking within the IBM PC compatible line from say '90 > forward? On Thu, 3 Nov 2022, Dennis Boone via cctalk wrote: There aren't that many platforms that used CLV drives. I don't recall seeing one in the PC

[cctalk] Re: Disk imaging n00b

2022-11-03 Thread Fred Cisin via cctalk
GCR stands for "group Coded Record" On Thu, 3 Nov 2022, Fred Cisin via cctalk wrote: Also GCR, not MFM.  NOT readable with a PC FDC. On Thu, 3 Nov 2022, Grant Taylor via cctalk wrote: Please expand "GCR". Sure, . . . (GROSSLY OVER-SIMPLIFIED, such as "pulse" instead of flux

[cctalk] Re: Disk imaging n00b

2022-11-03 Thread Paul Koning via cctalk
> On Nov 3, 2022, at 5:57 PM, Glen Slick via cctalk > wrote: > > On Thu, Nov 3, 2022 at 2:08 PM Grant Taylor via cctalk > wrote: >> >> Hi, >> >> n00b alert >> >> Does anyone have a 101 level boot strap guide for someone wanting to get >> into creating better-than-dd disk images? >> >>

[cctalk] Re: Disk imaging n00b

2022-11-03 Thread Sellam Abraham via cctalk
Fred, There was a project someone did years ago where you can read GCR disks in an unmodified PC drive by first inserting a PC formatted disk to get synced and then swapping in a GCR encoded disk, then it can actually read the raw pulses and they get decoded in software. I forget the website

[cctalk] Re: Disk imaging n00b

2022-11-03 Thread Fred Cisin via cctalk
On Thu, 3 Nov 2022, Sellam Abraham via cctalk wrote: There was a project someone did years ago where you can read GCR disks in an unmodified PC drive by first inserting a PC formatted disk to get synced and then swapping in a GCR encoded disk, then it can actually read the raw pulses and they

[cctalk] Re: Disk imaging n00b

2022-11-03 Thread Fred Cisin via cctalk
On Thu, 3 Nov 2022, Grant Taylor via cctalk wrote: Does anyone have a 101 level boot strap guide for someone wanting to get into creating better-than-dd disk images? I'm finding myself back in a position where I want to image / preserve multiple 5¼ & 3½ inch disks. I think all of them are PC

[cctalk] Re: Disk imaging n00b

2022-11-03 Thread Tomasz Rola via cctalk
On Thu, Nov 03, 2022 at 03:07:00PM -0600, Grant Taylor via cctalk wrote: > Hi, > > n00b alert > > Does anyone have a 101 level boot strap guide for someone wanting to get > into creating better-than-dd disk images? [...] > So, does anyone have a 101 level boot strap guide for someone wanting to

[cctalk] Re: Disk imaging n00b

2022-11-03 Thread Dennis Boone via cctalk
> Is Constant Linear vs Angular Velocity (?) anything I need to worry > about when sticking within the IBM PC compatible line from say '90 > forward? There aren't that many platforms that used CLV drives. I don't recall seeing one in the PC world. If anyone did, they would have been

[cctalk] Re: Disk imaging n00b

2022-11-03 Thread Grant Taylor via cctalk
On 11/3/22 5:07 PM, Dennis Boone via cctalk wrote: There aren't that many platforms that used CLV drives. I don't recall seeing one in the PC world. If anyone did, they would have been specialty stuff. ACK I haven't seen a flux imaging system for Zip/Jaz drives. MO stuff might be easier

[cctalk] Re: Disk imaging n00b

2022-11-03 Thread Fred Cisin via cctalk
On Thu, 3 Nov 2022, Paul Koning via cctalk wrote: An example of a non-PC format 5.25 inch disk that normal drives can read would be the DEC RX50 floppy, which has 10 sectors per track rather than the PC standard 9 sectors. But a standard drive will read and write those just fine, if it's told

[cctalk] Disk imaging n00b

2022-11-03 Thread Grant Taylor via cctalk
Hi, n00b alert Does anyone have a 101 level boot strap guide for someone wanting to get into creating better-than-dd disk images? I'm finding myself back in a position where I want to image / preserve multiple 5¼ & 3½ inch disks. I think all of them are PC compatible disks. Probably

[cctalk] Re: Disk imaging n00b

2022-11-03 Thread Dennis Boone via cctalk
> I was thinking about acquiring a Kryoflux in the next few months and > starting to collect better quality images of disks. I recently saw > someone on Twitter suggest that Kryoflux wasn't the best route to go > and suggested a SuperCard Pro instead. Some people are bothered by Kryoflux's

[cctalk] Re: Disk imaging n00b

2022-11-03 Thread Jon Elson via cctalk
On 11/3/22 16:07, Grant Taylor via cctalk wrote: Hi, n00b alert Does anyone have a 101 level boot strap guide for someone wanting to get into creating better-than-dd disk images? Is there a reason to do a real IMAGE backup, rather than a file backup?  I have used Linux to backup a lot of

[cctalk] Re: Disk imaging n00b

2022-11-03 Thread Grant Taylor via cctalk
On 11/3/22 3:27 PM, Dennis Boone via cctalk wrote: Some people are bothered by Kryoflux's behavior around openness of their formats and the like. I _think_ they've addressed that, but if you care about this, you will have to verify. Ya. I'm starting to see that. I don't /personally/ care

[cctalk] Re: Disk imaging n00b

2022-11-03 Thread Glen Slick via cctalk
On Thu, Nov 3, 2022 at 2:08 PM Grant Taylor via cctalk wrote: > > Hi, > > n00b alert > > Does anyone have a 101 level boot strap guide for someone wanting to get > into creating better-than-dd disk images? > > I'm finding myself back in a position where I want to image / preserve > multiple 5¼ &

[cctalk] Re: Disk imaging n00b

2022-11-03 Thread Sellam Abraham via cctalk
Fred, The Victor/Sirius 9000 was sort of PC compatible and featured a varial speed floppy format, no? Sellam On Thu, Nov 3, 2022 at 3:09 PM Fred Cisin via cctalk wrote: > >> Note that some disk types are CLV, not CAV (e.g. some Mac disks), and > >> reading them without additional hardware

[cctalk] Re: Disk imaging n00b

2022-11-03 Thread Fred Cisin via cctalk
But, why do IMAGING on PC-DOS disks? On Thu, 3 Nov 2022, Grant Taylor via cctalk wrote: My /personal/ and primary use case is for use in virtual machines where disk images (a la dd) is best (in my experience). THAT is a totally valid reason for disk images, rather than file copies. Another,

[cctalk] Re: Disk imaging n00b

2022-11-03 Thread Grant Taylor via cctalk
On 11/3/22 3:57 PM, Glen Slick via cctalk wrote: If they are 5¼ & 3½ inch disks which are not copy protected and are readable with standard PC compatible floppy controllers, but not necessarily limited to standard DOS formats, and you had a older PC with a floppy controller which you could set

[cctalk] Re: Disk imaging n00b

2022-11-03 Thread Fred Cisin via cctalk
> Is there a reason to do a real IMAGE backup, rather than a file > backup? On Thu, 3 Nov 2022, Dennis Boone via cctalk wrote: People have occasionally found interesting things in the unallocated sectors of disks. For garden variety PC format disks, it's not necessary to do flux imaging to

[cctalk] Re: Disk imaging n00b

2022-11-03 Thread Fred Cisin via cctalk
Also GCR, not MFM.  NOT readable with a PC FDC. On Thu, 3 Nov 2022, Grant Taylor via cctalk wrote: Please expand "GCR". Sure, . . . (GROSSLY OVER-SIMPLIFIED, such as "pulse" instead of flux transition) FM is "frequency modulated". Well, it is actually a regular clock pulse, with data

[cctalk] Re: Disk imaging n00b

2022-11-03 Thread Paul Koning via cctalk
> On Nov 3, 2022, at 7:38 PM, Fred Cisin via cctalk > wrote: > > On Thu, 3 Nov 2022, Paul Koning via cctalk wrote: >> An example of a non-PC format 5.25 inch disk that normal drives can read >> would be the DEC RX50 floppy, which has 10 sectors per track rather than the >> PC standard 9

[cctalk] Re: Disk imaging n00b

2022-11-03 Thread Sellam Abraham via cctalk
Here's something right out of the Apple II FAQ: 07.007 Can I read Apple II diskettes on my PC? Yes. There is a way for some PCs to read Apple II DOS 3.3 and ProDOS 5.25" floppies which are not copy-protected. By "some PCs" I mean that the PC must have two floppy drives (only one

[cctalk] Re: Disk imaging n00b

2022-11-03 Thread Grant Taylor via cctalk
On 11/3/22 3:26 PM, Tomasz Rola via cctalk wrote: I am (slowly) on my way to use ddrescue for similar thing(s). I've used ddrescue for a /few/ of my disk images. Thankfully /most/ of the 3½ disks that I've imaged have not needed ddrescue / SpinRite / et al. -- Grant. . . . unix || die

[cctalk] Re: Disk imaging n00b

2022-11-03 Thread Grant Taylor via cctalk
On 11/3/22 3:26 PM, Fred Cisin via cctalk wrote: But, why do IMAGING on PC-DOS disks? My /personal/ and primary use case is for use in virtual machines where disk images (a la dd) is best (in my experience). Why not just copy the files, and "ZIP" them? Ziped (et al.) files are nice for

[cctalk] Re: Disk imaging n00b

2022-11-03 Thread Fred Cisin via cctalk
Note that some disk types are CLV, not CAV (e.g. some Mac disks), and reading them without additional hardware support may be problematic. On Thu, 3 Nov 2022, Grant Taylor via cctalk wrote: Is Constant Linear vs Angular Velocity (?) anything I need to worry about when sticking within the IBM

[cctalk] Re: Disk imaging n00b

2022-11-03 Thread Dennis Boone via cctalk
> Is there a reason to do a real IMAGE backup, rather than a file > backup? People have occasionally found interesting things in the unallocated sectors of disks. For garden variety PC format disks, it's not necessary to do flux imaging to preserve that sort of thing, though. A regime using a

[cctalk] Re: Disk imaging n00b

2022-11-03 Thread Grant Taylor via cctalk
On 11/3/22 4:35 PM, Fred Cisin via cctalk wrote: Also GCR, not MFM.  NOT readable with a PC FDC. Please expand "GCR". -- Grant. . . . unix || die

[cctalk] Re: Disk imaging n00b

2022-11-03 Thread Mike Katz via cctalk
GCR is Group Code Recording, used on the Apple II, Commodore 1541 drive and Amiga (and others) use a different encoding scheme than the normal FM (Frequency Modulation) or MFM (Modified Frequency Modulation) encoding formats used by a majority of floppy disk controllers. There is a very good

[cctalk] Re: Disk imaging n00b

2022-11-03 Thread Fred Cisin via cctalk
On Thu, 3 Nov 2022, Mike Katz via cctalk wrote: GCR is Group Code Recording, used on the Apple II, Commodore 1541 drive and Amiga (and others) use a different encoding scheme than the normal FM (Frequency Modulation) or MFM (Modified Frequency Modulation) encoding formats used by a majority