> Date: Wed, 30 May 2001 07:09:51 GMT
> From: pete(a)dunnington.u-net.com (Pete Turnbull)
> Subject: Re: New HD disks not working in 1541?
> On May 30, 3:52, Gunther Schadow wrote:
> > now that I have my old C64 setup back I found that I could not
> > format newer 5.25" HD disks on the 1541 or 1571.
Yep DD even reccomended for the 8050,8250 or SFD1001 (which are quad
density drives), HDs 3.5" kinda work in 1581s but also aren't
reccommended. Over the past few years I've cleaned out our local
'dollar'ish stores of 5.25" disk 10-packs when they get em.
As for hub rings I heard they were required (for gripping purposes) for
the older Apple drives (the metal boxy ones), maybe even for the 4040s,
but I know without them on those old lever drives, you could sure mangle
a non-protected center hole clamping down on one.
Anyone have a hub-ring kit still? (reminds me of today's CD stompers)
> As others have said, you need disks intended for single-density or double
> density, not HD. I've also met one 1541 owner who swears that disks
> without hub rings won't work in his drive (and never did) because the
> mechanism doesn't grip them tightly enough (though I'm fairly sure that's
> just due to a soft spring or a missing screw on the frame somewhere).
01000011 01001111 01001101 01001101 01001111 01000100 01001111 01010010 01000101
Larry Anderson - Sysop of Silicon Realms BBS (209) 754-1363
Classic Commodore pages at: http://www.jps.net/foxnhare/commodore.html
01000011 01001111 01001101 01010000 01010101 01010100 01000101 01010010 01010011
Hello. I'd like some of yours take a time to read this document
that can be located in the URL
It's dated in 1991. It contains some amazing projects. Oh, by the way,
finally we know where goes all these old irons lost: to India. And I appoint
the convenience to try contact this guy to know if some of these projects
was completed (mainly the diskette unit for the IBM 1401, or the COBOL
compiler for this same computer).
(Referred to in Para 9.1.5)
Projects undertaken under Research & Development Activities.
1. System Integration Project. To integrate an optimum medium large computer
system with the processor and peripherals from various sources.
2. Add-on memory for EC-1030 system. To design and provide indigenously
additional memory to EC-1030 computer system.
3. Enhancement to computer system with Line Printer and Card Reader add-on.
4. Enhancement to computers with disk and console sub-system add-on.
5. IBM 1401 enhancement project- to provide a faster processor with a larger
memory and additional instruction set, keeping the same peripheral.
6. Add-on memory for EC-1040 computer system. To design and provide
indigenously additional memory to EC-1040 computer system.
7. Input/output controllers for low speed peripherals such as card reader
and line printer.
8. Computer enhancements with indigenous communication terminus.
9. Development of IBM 1401 simulator programme on R-1040 computer system.
10. Development of application software for gross industry application
11. Enhancement of IBM 1620 computer system. To design and develop
enhancement logic and interface hardware to attach a line printer.
12. Evaluation of Robotron Card Punch and verifier Model I.
13. Evaluation of Hindustan Teleprinter High Speed paper tape reader.
14. Evaluation of Robotron Card punch and verifier Model II.
15. Enhancement of Card Reader speed of IBM 447 Electronic Accounting
16. Enhancement of IBM 024 card punch to enable it to become 64 character
machine from 48 character machine.
17. Design and development to replace obsolete assemblies in IBM unit red
cord machines with indigenously available components.
18. Development of parts used in computer system.
19. Development of logic card test equipment.
20. Application software development on LSI-II Computer System.
21. 1620 Memory Enhancement.
22. 024/056 Logic in TTL/CMOS.
23. IBM Unit Record Machine replacement study.
24. Info Scriber
25. Special keyboards for Indian languages.
26. LSI-11 based online enquiry system directory enquiry etc.
27. Medical equipment based on micro-processors.
28. New Products like fibre optics special printers, bubbles etc.
29. Evaluation of l/D's.
30. pcb Card Repair Project.
31. Development of maintenance technique, diagnostic test equipment for
32. Mini based system for RJE and Data Entry.
33. Graphic sub system.
34. Data based application packages.
35. Interactive Data Communication application packages.
36. Special application packages.
37. Image sub system.
38. Development of interactive work station.
39. Development of Computer System using mini computer network.
40. Hybrid system integration.
41. Floppy disc interface to IBM 1401 system. To design and develop a floppy
disc interface to IBM 1401 system.
42. Development of COBOL compiler for enhancement of IBM 1401 processor.
43. Teleprinter interface job unit for mini computer.
44. Message switching system with micro processors.
45. Process control application with micro processors.
46. Communication application with micro processors and mini systems.
I've got a 9404-400 running v4r5. The system has a Qic tape drive and CD.
I have a 8mm drive that I want to add to the system. The expansion
chassis has room and open connectors. I hooked up the new drive, but I
cannot seem to make the system 'see' it.
What do I need to do to make the system see the drive so I can use it??
Any suggestions are appreciated, Thanks in advance
Little know facts about apple turnovers.
1. The hard part is convincing the apple to turn over when it's done on one
side. A human analogy is how do you convince a sleeping sunbather to turn
over when they are burnt on one side.
2. There have been government funded trials of robot arm based image
analysis programs that will automate the process for only $10,000 per apple
to be turned over. The only successful installation is in the International
Space Station where gravity is not a factor so the apple will turn over due
to convection currents in the air flow. That's where the term convection
oven comes from.
3. There are also CIA funded research to examine whether there is a "apple
turnover gap" due to Russian experiments with apples and psychic phenomena.
4. Apple turnover is a code word that Echelon uses to identify Russian
defectors. apples are red and Russians are red, defectors are turncoats or
turnovers. Russian defector=red apple turnover
5. Board game
6. Q: When does an apple turnover? A: Who Cares
now that I have my old C64 setup back I found that I could not
format newer 5.25" HD disks on the 1541 or 1571. It just bumps
and blinks and stops. Does the 1541 require hard sectored disk?
I don't think so, because I can still remember today that my first
disk ever said "BASF Flexi Disk, 5.25", Singled Side, Double
Density, Soft Sector." So what's the trick to get media working?
Bulk eraser? (BTW: It's been over 15 years and I still have that
disk and could actually read one side of it, that's fun!)
Gunther Schadow, M.D., Ph.D. gschadow(a)regenstrief.org
Medical Information Scientist Regenstrief Institute for Health Care
Adjunct Assistant Professor Indiana University School of Medicine
On May 30, 14:23, Roger Merchberger wrote:
> HD disks AFAIK won't work at all in any DD drive - the TPI (Tracks Per
> Inch) are different. DD disks are 48TPI, HD disks are 96TPI.
I have to say that this is not true.
Plenty of DD disks are rated for 96 or 100 tpi. Furthermore, at the
microscopic level, there is no difference between a DD disk sold for 96 tpi
and one sold as 48 tpi. There might be more gross defects in older
sold-as-48 tpi disk than in 96 tpi ones, I admit, and that could produce an
error when narrow tracks are written. Nevertheless, the magnetic
coercivity of the disk is the same in both cases.
The difference between HD and DD is NOTHING to do with tracks per inch,
it's ENTIRELY to do with the coercivity (which is a measure of the field
strength required to produce the magentic polarisation used to write the
Pete Peter Turnbull
University of York
On May 30, 11:02, Gene Buckle wrote:
> I don't ever recall seeing a HD disk with a hub ring. The only ones that
> have them in my experience is the SD or DD disks.
Oh, I've seen quite a few HD disks with hub rings. But most of the disks
I've seen with hub rings have been relatively recent DD/SD.
However, the reason I menmtioned it was that the 1541 owner insisted that
she needed DD disks *because they had hub rings*, not because they are the
correct coercivity; in fact she said she'd used a few HD disks but the lack
of hub rings on some of them caused them not to work. So told her she was
using the right disks (DD) but for the wrong reason.
Pete Peter Turnbull
University of York