Search found 2146 matches

by ijor
Sat Aug 19, 2017 9:33 pm
Forum: Development
Topic: Steem LE
Replies: 23
Views: 565

Re: Steem LE

Steven Seagal wrote:Not many responded but those who did seem to prefer an 'advanced' switch, so I've been pondering...


Now you can advertise ... "we listen to the customers" :)
by ijor
Thu Aug 17, 2017 5:06 pm
Forum: Development
Topic: Steem LE
Replies: 23
Views: 565

Re: Steem LE

Oh, I didn't realize it was already suggested and you already replied. Sorry :oops:
by ijor
Thu Aug 17, 2017 3:02 pm
Forum: Development
Topic: Steem LE
Replies: 23
Views: 565

Re: Steem LE

May be instead of a different build, just a mode? Normal and expert mode? Just an idea, but the concept it is used nowadays ...
by ijor
Wed Aug 16, 2017 8:53 pm
Forum: ST(E) Clones (Suska / MiST)
Topic: AMIGA: MIST vs Pi3 vs Vampire/real Amiga (4000?)
Replies: 23
Views: 964

Re: AMIGA: MIST vs Pi3 vs Vampire/real Amiga (4000?)

Personally, I am happy that we host the Mist (and related hardware) subforums. And as long as those few thread not related to Atari are restricted to Mist, Mister or similar clones, I don't mind.
by ijor
Tue Aug 15, 2017 4:20 pm
Forum: Hardware
Topic: 520ST External Floppy only
Replies: 32
Views: 934

Re: 520ST External Floppy only

joska wrote:I don't *know*, but my theory is that the single sided drive mechanism used in those particular SF354's were not proper Shugart drives, and this extra logic compensated for that.


Can you check which signals go to the 8048?
by ijor
Sat Aug 12, 2017 11:55 am
Forum: Hardware
Topic: 520ST External Floppy only
Replies: 32
Views: 934

Re: 520ST External Floppy only

Very interesting, can you trace which signals are "intercepted" by the 8048?
by ijor
Sat Aug 12, 2017 11:48 am
Forum: Development
Topic: Hardware Overscan
Replies: 77
Views: 3647

Re: Hardware Overscan

Yet, some programs seem to rely on the counter being reloaded again at the end of VSYNC, when the VBL interrupt is set pending Sorry, I was wrong. The video pointer is updated whenever VSYNC is asserted. But it is not exactly that it is reloaded again at the end of VSYNC, it is constantly being rel...
by ijor
Fri Aug 11, 2017 12:06 pm
Forum: ST(E) Clones (Suska / MiST)
Topic: Introducing the VeriSNES (FPGA-based SNES)
Replies: 29
Views: 3810

Re: Introducing the VeriSNES (FPGA-based SNES)

Hi jwdonal, Welcome aboard. Till Harbaum is the MiST original board designer. But we haven't heard from him for a while here. For developing questions may be other core developers can help you. There are several here. If you are looking for a free board, then unless people here would donate the mone...
by ijor
Tue Aug 08, 2017 11:55 am
Forum: ST(E) Clones (Suska / MiST)
Topic: Introducing the VeriSNES (FPGA-based SNES)
Replies: 29
Views: 3810

Re: Introducing the VeriSNES (FPGA-based SNES)

To be honest, I don't sympathize with the idea too much. It is true that I never owned a NES or SNES, so I don't have any sentimental links with the console. And then I don't mind too much if the core is released or not. But asking the community (not a company), for big money to open source a projec...
by ijor
Tue Aug 08, 2017 1:09 am
Forum: Games - Requests
Topic: Rogue
Replies: 53
Views: 2650

Re: Rogue

At the same time, i don't see why Mastertronic would have use procopy when any standard duplicator can replicate this protection. I don't have a fully reasonable explanation about what's going on with this release. As far as we know it doesn't even work correctly, so hard to know what really happen...
by ijor
Mon Aug 07, 2017 2:02 am
Forum: Games - Requests
Topic: Rogue
Replies: 53
Views: 2650

Re: Rogue

More technical details about the Mastertronic release The disk seems to be mastered and duplicated in two different devices. The regular tracks (0-78) on one hand seem professionally duplicated. While the copy protected track, track 79, seems to be done separately. This track is not a faithful repro...
by ijor
Mon Aug 07, 2017 1:19 am
Forum: Games - Requests
Topic: Rogue
Replies: 53
Views: 2650

Re: Rogue

The original Epyx release is good. It just requires TOS 1.0 for the reasons I mentioned earlier. The SCP image didn't work in Steem because the bug that Steven fixed. It affected the internal Steem emulation only (not Pasti). Brume's dump is the Epyx release. Or at the very least is not the Mastertr...
by ijor
Sat Aug 05, 2017 11:54 am
Forum: Development
Topic: Hardware Overscan
Replies: 77
Views: 3647

Re: Hardware Overscan

That's interesting (I'm sure the schematic is right). There's thus unnecessary logic in GLUE handling BLANK in mono without it actually being used (unless you trick the GLUE by triggering the BLANK position for mono while otherwise in color). Yes, GLUE processes BLANK exactly with the same logic as...
by ijor
Sat Aug 05, 2017 11:27 am
Forum: Games - Requests
Topic: Rogue
Replies: 53
Views: 2650

Re: Rogue

Ok, please tell me how to put it and i'll update the text. I'm not a coder or know nothing about disk protections so i don't know anything about what's happening "inside the disk". If i write it requires TOS 1.0 i get reports that it works even though people won't play it enough to unders...
by ijor
Sat Aug 05, 2017 1:12 am
Forum: Games - Requests
Topic: Rogue
Replies: 53
Views: 2650

Re: Rogue

I happen to have a dump of the Mastertronic budget release, and it's pretty weird. According to my notes, I made the dump myself years ago from a shrink wrapped brand new package. Seems the disk was mastered from a used copy. Something that was not that uncommon on budget releases. There are traces ...
by ijor
Sat Aug 05, 2017 12:44 am
Forum: Games - Requests
Topic: Rogue
Replies: 53
Views: 2650

Re: Rogue

So, this is because TOS 1.00 XBIOS 8 function implementation gives different return value in d0 in case of CRC error... Yes, there is a bug in TOS 1.0 that reading a sector with CRC error might not return any error at all, as if the sector would be ok. This is related to how the FDC read multiple s...
by ijor
Thu Aug 03, 2017 5:05 pm
Forum: Games - Requests
Topic: Rogue
Replies: 53
Views: 2650

Re: Rogue

Short answer: Bad protection implementation, it needs TOS 1.0 Will elaborate later, but the original image at Atarimania seems good. Didn't test the others yet, but probably they are ok. Tested with TOS 1.0 US and 512K RAM. But probably runs ok with any TOS 1.0 and with 1MB RAM as well. Will elabora...
by ijor
Fri Jul 28, 2017 3:43 pm
Forum: Games - Requests
Topic: Rogue
Replies: 53
Views: 2650

Re: Rogue

I'm currently out of home. Will check it next week. In the meantime, if somebody has a Pasti STX image made directly on a real ST (not converted from RAW images), it might be helpful.
by ijor
Tue Jul 18, 2017 12:50 am
Forum: SuperCard Pro Disk Copier
Topic: SCP disk images !
Replies: 540
Views: 116269

Re: SCP disk images !

What 3.5" drive did you test? I don't see this with Samsung 321 and a few others that I have tested. TEAC combo (3.5 and 5.25). Can't check the exact model number right now. Note that they are really two piggybacked independent drives. But fitting in a single internal bay, the combo is very co...
by ijor
Fri Jul 14, 2017 6:14 pm
Forum: Hardware
Topic: CPU -> shifter bus cycle timing
Replies: 6
Views: 350

Re: CPU -> shifter bus cycle timing

So, from what you said in your other post, I guess we can theorise that CS (AKA CMPCS off the MMU) must be generated using a fixed delay inside the MMU, rather than being passed through from UDS/LDS which is where the CPU would normally indicate that it wants a device to receive the contents of the...
by ijor
Fri Jul 14, 2017 1:03 pm
Forum: Hardware
Topic: CPU -> shifter bus cycle timing
Replies: 6
Views: 350

Re: CPU -> shifter bus cycle timing

Read cycle: While CS and READ (R/W high) are asserted, the data bus is continuously driven with the value of whichever register is indexed by A1:5. When either is deasserted, shifter releases the bus. Mostly correct, except that Shifter is not really connected directly to the main data bus. It is c...
by ijor
Fri Jul 14, 2017 7:52 am
Forum: SuperCard Pro Disk Copier
Topic: SCP disk images !
Replies: 540
Views: 116269

Re: SCP disk images !

Well, now I measured with a 3.5" drive. Hall sensor or not, the jitter is not much better than the 5.25" drive I measured before. Index edge jitter is still in the order of microseconds. This is not a track shift, I captured multiple consecutive revolutions, and the index pulse relation to...
by ijor
Mon Jul 10, 2017 7:19 pm
Forum: CosmosEx
Topic: MicroCosmos sad news...
Replies: 29
Views: 3158

Re: MicroCosmos sad news...

Timing depends, of course, on the CPU as well. I don't have personal experience with the CMOS part, but the 68HC is supposed to be fully compatible, even on undocumented features. The asynchronous delays in the same cycle, such as tCO, are probable smaller (note that doesn't mean less cycles). Conce...
by ijor
Sun Jul 09, 2017 9:13 pm
Forum: SuperCard Pro Disk Copier
Topic: SCP disk images !
Replies: 540
Views: 116269

Re: SCP disk images !

JimDrew wrote:This a hall sensor that triggers on a magnet passing. It's not like an optical sensor where the index hole can be slightly off depending on how the disk centers.


It is an optical sensor. As I noted, it's a 5.25' drive, not a 3.5" one.
by ijor
Sun Jul 09, 2017 6:51 pm
Forum: SuperCard Pro Disk Copier
Topic: SCP disk images !
Replies: 540
Views: 116269

Re: SCP disk images !

Jitter from an index pulse sensor is expected, but it's only measured in tens of nanoseconds. I use standard off the shelf hall sensors in critical flight control system applications for measuring positions with incredible accuracy. I am sure every type of drive is different for accuracy, but I hav...

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