Page 3 - To move disks between simulators and real hardware
Disk Imaging – Why? • To make real system and application disks for our vintage computers using disk images found online • To archive and share our stash of vintage computer disks – before its too late! • To accurately duplicate disks - including most “copy protected” disks • To “format shift” – for...
Page 4 - Applicability; Single-density disks loosely based on the “IBM 3740” (FM) format
Applicability • Discuss ways of reading and writing floppy disks created on systems based on the WD1771 family and its descendants (WD1771, WD179x, WD 279X) - eg: • Single-density disks loosely based on the “IBM 3740” (FM) format • Double-density disks loosely based on the “IBM System 34” (MFM) form...
Page 5 - Floppy Disk Media Considerations
Floppy Disk Media Considerations • A significant portion of older disks (perhaps 5 to 10%) are failing due to age and/or poor storage conditions • Failure modes include: • Warped and physically damaged disks • Cloudy / mould affected • Oxide detachment on first read SO: • Test the drive before putti...
Page 6 - Floppy Disk Encoding Techniques
Floppy Disk Encoding Techniques Sourced from: Siemens FDD 100-8 Technical Manual, page 1-5
Page 7 - IBM 3740 Track Format – For SD (FM) 8” Floppy
IBM 3740 Track Format – For SD (FM) 8” Floppy Sourced from: Siemens FDD 100-8 Technical Manual, page 1-7
Page 9 - ImageDisk
ImageDisk • Written by Dave Dunfield • Uses the PC’s own FDC [built-in or plug-in] • MSDOS only • Package includes: • TESTFDC.COM – Tests capabilities of FDC • IMD.COM – Read/Write disk images, format disks, exercise heads • IMDU.COM – Image manipulation (convert to binary or uncompressed files, etc...
Page 10 - ImageDisk – Main Screen
Page 11 - ImageDisk – Result of Reading a Disk
Page 12 - ImageDisk - Limitations; data address marks used by Model 1 TRSDOS
ImageDisk - Limitations Excellent highly useful suite of programs. Very well documented. Limitations are: 1. IMD images not widely supported by simulators [???] 2. Most PC motherboard FDC’s don’t support single-density (FM) 3. NEC765 derivatives suffer “blindness” after index pulse -> lost data 4...
Page 13 - Catweasel
Catweasel • Is a floppy disk controller card [with other Amiga-related features] • Designed by Individual Computers • No longer available • Some online shops show stock available – but are out of stock! • PCI versions were MK 3 and MK 4 • Not subject to the limitations of NEC765-compatible FDC’s • L...
Page 14 - Catweasel MK 3 PCI Card
Page 15 - Other Options for Disk Imaging
Other Options for Disk Imaging Techniques that capture raw flux transition data: 1. KryoFlux http://www.kryoflux.com/ Standalone board with USB interface Commercial product. Closed source [???]. Licence restrictions apply [??]. 2. DiscFerret http://discferret.com/wiki/DiscFerret:FAQ Standalone board...
Page 17 - Connecting a vintage 5.25” drive to PC FDC
Connecting a vintage 5.25” drive to PC FDC Remember: 1. Drive must be configured as DS1 (not DS0) 2. Keep it simple – one drive only 3. Terminating resistors must be fitted – all signals are open-collector 4. Connect drive to end of cable (connecting mid- cable may cause signal reflection problems) ...
Page 18 - Connecting an 8” drive to PC FDC
Connecting an 8” drive to PC FDC Things to be aware of: 1. Configure floppy drive to respond to DS0 2. Check HL, Motor-On & Side-Select jumpers 3. Consider TG43 – Is it needed? 4. Terminating resistors must be fitted – all signals are open-collector 5. Connect drive to end of cable (connecting m...
Page 19 - Using D-Bit’s FDADAP Floppy Disk Adapter
Using D-Bit’s FDADAP Floppy Disk Adapter • Use 34-way “straight through” cable from PC FDC to FDADAP • Use 50-way “straight through” cable from FDADAP to 8” Drive • ImageDisk will see the drive as “Drive A”
Page 20 - Power Supply Options for +24 VDC for 8” Drives
Power Supply Options for +24 VDC for 8” Drives 1. D-Bit’s FDDC • http://www.dbit.com/fddc.html • DC-DC Adapter • Powered by IDE connector OR standalone ATX power supply • $80 including postage • Not (yet) used by me 2. Mean Well NES-100-24 • +24 VDC 4.5A • $27 on eBay from China
Page 21 - Tandon TM848E - Jumper Settings
Page 26 - Using “TESTFDC” to determine FDC capabilities
Using “TESTFDC” to determine FDC capabilities The testing process is as follows: 1. Connect a 250 kpbs drive to your PC – eg: a) 5.25” 360K drive (Teac FD-55Bx series) b) 3.5” HD drive with 720K media 2. Change your PC’s BIOS settings to 5.25 360K, or 3.5” 1.44MB, as applicable 3. Boot MSDOS 4. Run ...
Page 27 - TESTFDC – D7600 Motherboard with 3.5” HD Drive
Page 28 - TESTFDC – D7600 Motherboard with 5.25” HD Drive
Page 29 - Boards Tested using TESTFDC:; Asus P3W Motherboard
Boards Tested using TESTFDC: 1. ECS P6BA-A+ 2. Asus P3W Motherboard 3. Generic Pentium 166 Desktop 4. HP Vectra D7600-6000 Motherboard 5. Dell GX280 Desktop (SFF & LFF) 6. HP Vectra VE Series 8 DT 7. Adaptec AHA-1522A SCSI/Floppy ISA Card
Page 31 - Asus P3W Motherboard
Page 32 - Generic Pentium 166 Desktop
Page 34 - Dell GX280 LFF Desktop
Page 35 - HP Vectra VE Series 8 DT
Page 37 - TESTFDC Results
Computer / Controller 250 S D X 300 S D X 500 S D X ECS P6BA-A+ Motherboard F P F F P F F P F Asus P3W Motherboard (Tested using 3.5” 1.44M drive only) F P F N N N F P F Generic Pentium 166 Desktop (Tested using 3.5” 1.44M drive only) F P F N N N F P F HP VECTRA D7600-6000 Motherboard P P F F P F P ...
Page 40 - Suggested PC setup for IMD and CW
Hardware: • Any mid to late 1990’s PC motherboard • ATX power supply • PS2 keyboard • VGA display • IDE to CompactFlash card adapter • 2G (or bigger) CF card • D-Bit’s FDADAP 8” adapter • 34-way & 50-way floppy cables • 24VDC power supply (for modern 8” drives) • 3-wire RS232 null-modem cable • ...
Page 43 - Adaptec AHA-1522A SCSI Card with Floppy Interface
Adaptec AHA-1522A SCSI Card with Floppy Interface • Does SD, DD & DD/128 at 250, 300 and 500 kpbs • No drivers required • $15 to $50 on eBay Caution: Only buy the “-1522A” version (“-1520A” uses same PCB but no FDC)
Page 45 - CompactFlash Card & IDE Adapter; Can be used in place of an IDE hard drive
CompactFlash Card & IDE Adapter • Can be used in place of an IDE hard drive • Attaches directly to the motherboard • Allows easy means to transfer disk images files between imaging PC and your regular PC (via USB-CF adapter)
Page 46 - Using Tim Mann’s Catweasel Tools; dmk2cw –d1 –k2 filename.dmk
Using Tim Mann’s Catweasel Tools • Reading a 5.25” SD or DD disk: cw2dmk –d1 –k2 [–s1] [–t35] –v42 filename.dmk • Writing a 5.25” SD or DD disk: dmk2cw –d1 –k2 filename.dmk • Reading a 3.5” HD disk: cw2dmk –d1 –k4 –v42 filename.dmk • Writing a 3.5” HD disk: dmk2cw –d1 –k4 filename.dmk • Reading an 8...