Search found 648 matches

by iss
Tue May 08, 2018 4:15 pm
Forum: Operating systems
Topic: FastBoot/FastLoad on Pravetz 8D/Disk II
Replies: 35
Views: 4042

Re: FastBoot/FastLoad on Pravetz 8D/Disk II

@ThomH: Yep, you are right - there is no physical interleaving on real disks too. Else bringing the old DISK][ back to life is almost done I'll post pictures/video of the result soon. :) I've created small utility for calibration of the rotation speed. It's based on old utility for Apple ][ which I ...
by iss
Tue May 08, 2018 3:22 pm
Forum: General Discussion
Topic: Oric Explorer v2.0 is up for adoption!!!
Replies: 10
Views: 1250

Re: Oric Explorer v2.0 is up for adoption!!!

Great news about resurrecting OricExplorer! Actually, I was one of the few lucky to download sources when they were available on the main site. So I have since long time sources of both versions: Screenshot_20180508_163336.png Maybe you have something which is more recent. Else about the portability...
by iss
Mon May 07, 2018 12:45 am
Forum: Technical questions
Topic: Oric-1 16k memory management
Replies: 8
Views: 837

Re: Oric-1 16k memory management

Geoff Phillips says in his book : 1.4 Differences between machines From the point of view of hardware, there are very few differences between machines. There are two major categories: Your Oric is either a 16K or a 48K machine. Your Oric is either version 1.0 (i.e., the ORIC-1) or 1.1 (i.e., the ORI...
by iss
Sun May 06, 2018 11:24 pm
Forum: Tape and floppy disk converters
Topic: Experimental very fast tape loading
Replies: 132
Views: 20310

Re: Experimental very fast tape loading

Some of my Orics have zener diodes at the input of the OpAmplifier. The idea is to limit the input amplitude of the signal (also good for protection) but this can change the required volume level. If you can open your Orics and take pictures on the analog part (on left side of the ULA) and note whic...
by iss
Sat Apr 28, 2018 1:33 pm
Forum: Operating systems
Topic: FastBoot/FastLoad on Pravetz 8D/Disk II
Replies: 35
Views: 4042

Re: FastBoot/FastLoad on Pravetz 8D/Disk II

I've created simple utility which prints the order of sectors in each track. It's based on the loading routine. The sector number is extracted from the address field. I expected to see some interleave but the result shows natural order ... which puzzles me :shock: . In Oricutron: mapper.jpg And with...
by iss
Sat Apr 28, 2018 1:16 pm
Forum: Operating systems
Topic: FastBoot/FastLoad on Pravetz 8D/Disk II
Replies: 35
Views: 4042

Re: FastBoot/FastLoad on Pravetz 8D/Disk II

Apple nibbles are '5+3' for the old 13 sector format, and '6+2' for the 16 sectors format which we are using. First are read 256 octets, they hold 256 x 6-bit bytes and next 86 octets give additional 2 bits. I succeeded to fix loading with help of temp 256-bytes buffer without any speed impact! :) H...
by iss
Thu Apr 26, 2018 9:31 pm
Forum: Operating systems
Topic: FastBoot/FastLoad on Pravetz 8D/Disk II
Replies: 35
Views: 4042

Re: FastBoot/FastLoad on Pravetz 8D/Disk II

So no a bug... a feature ? ;)
Sure! The most important thing is always to think positively :).
by iss
Thu Apr 26, 2018 9:27 pm
Forum: Technical questions
Topic: 8DOS: overlay RAM control?
Replies: 6
Views: 830

Re: 8DOS: overlay RAM control?

I guess the engineers at Pravetz really internalised the idea of soft switches! The engineers from Pravets only stole Oric but they forgot to 'borrow' Microdisc too. :) The FDC is entirely 'one man show' - the author of the hardware and DOS-3.3 adaptation is Borislav Zachariev - student at that tim...
by iss
Thu Apr 26, 2018 8:43 pm
Forum: Operating systems
Topic: FastBoot/FastLoad on Pravetz 8D/Disk II
Replies: 35
Views: 4042

Re: FastBoot/FastLoad on Pravetz 8D/Disk II

Thanks for the rich info about NIB and WOZ image formats, ThomH! The minimum I wish to add to Oricutron is support of any sector interleave. Else I think it's not worth to add half- and quarter-track positioning ability and all that stuff which in the Apple's world is used for different protection s...
by iss
Thu Apr 26, 2018 8:09 pm
Forum: Technical questions
Topic: 8DOS: overlay RAM control?
Replies: 6
Views: 830

Re: 8DOS: overlay RAM control?

Everything you wrote is correct. 8D FDC is exactly the same as Apple][ and it uses the 16-sector WOZ state machine P6 ROM. All 16 FDC registers are the same and are mapped at $310..$31F. There are only 2 differences from Apple: - no slots ; - boot ROM is shorter version - only 224 bytes instead of A...
by iss
Tue Apr 24, 2018 11:13 pm
Forum: Operating systems
Topic: FastBoot/FastLoad on Pravetz 8D/Disk II
Replies: 35
Views: 4042

Re: FastBoot/FastLoad on Pravetz 8D/Disk II

Well done - the "special build" works! I'll make a clip tomorrow. But I noticed one bad effect - in an undetermined moment graphics mode is switched back to text :?, pictures continue to be loaded but the mode remains text. In ~90% of cases when this happens is the Oric-1 picture just loaded, but I ...
by iss
Sat Apr 21, 2018 1:07 pm
Forum: Technical questions
Topic: oric atmos boot stuck at AA pattern
Replies: 14
Views: 1488

Re: oric atmos boot stuck at AA pattern

Nice work, seb! About the R0* in my old post - it depends on amplification of the particular chosen transistor - it should be in range 200 Ohms ... 2kOhms, or maybe even more. It's not danger to experiment with any R value, the best is to use 10k trimmer and adjust the picture. I think you can get b...
by iss
Fri Apr 20, 2018 11:11 pm
Forum: Operating systems
Topic: FastBoot/FastLoad on Pravetz 8D/Disk II
Replies: 35
Views: 4042

Re: FastBoot/FastLoad on Pravetz 8D/Disk II

Well, I finished the new controller and I'm very happy to say it works perfect! On the right is old broken one FDC, on the left - the new beast (still with trimmers for fine adjusting of the MAP signal), 20180421_000450.jpg And here is my version of the slideshow "as is" running on real hardware: :s...
by iss
Fri Apr 20, 2018 10:48 pm
Forum: Tape and floppy disk converters
Topic: FloppyBuilder evolution
Replies: 89
Views: 47113

Re: FloppyBuilder evolution

I'm advancing slowly in FloppyBuilder for 8D-FDC hardware. Here you can see optimized version of my test demo from previous post running on real 8D FDC. It's faster than in Oricutron :). [media]https://youtu.be/Vs5_dNjJal0[/media] I'll make some code cleanup and will post sources and all technical d...
by iss
Tue Apr 17, 2018 10:33 pm
Forum: Technical questions
Topic: Microdisc connectors
Replies: 10
Views: 1716

Re: Microdisc connectors

Generally powering trough expansion slot is not wrong and it 'highly likely' ;) will work always. Although for me it's not good practice for very simple reason - the purpose of ribbon cables (and connectors) are to be signal cables i.e. for low currents (for instance about 100mA) where Oric wants >6...