Search found 118 matches

by ThomH
Mon May 21, 2018 4:18 pm
Forum: 6502 assembly coding
Topic: 6502 flags C, N, Z, V and tests
Replies: 2
Views: 70

Re: 6502 flags C, N, Z, V and tests

In case it helps to offer any exposition as to `CLV`, 6502s have a dedicated input pin, SO, which when asserted will s et o verflow. It's there in case the hardware design requires a low-latency polling input: CLV ; clear V in preparation to wait... .loop BVC loop ; repeat until V is set That gets y...
by ThomH
Wed May 16, 2018 2:43 pm
Forum: Emulators
Topic: Clock Signal — an Oric emulator for macOS and Linux
Replies: 57
Views: 21316

Re: Clock Signal — an Oric emulator for macOS and Linux

* doesn't affect the Oric. But, essentially, nowadays if you insert a piece of media for which the correct machine or hardware configuration cannot be determined a priori, the proper machine and configuration will be found empirically. E.g. if you provide a 16kb file with a .bin extension and the e...
by ThomH
Wed May 16, 2018 2:53 am
Forum: Emulators
Topic: Clock Signal — an Oric emulator for macOS and Linux
Replies: 57
Views: 21316

Re: Clock Signal — an Oric emulator for macOS and Linux

I've released a new version to GitHub . Most interesting features: Pravetz 8DOS support (read-only at present); text pasting is unbroken for the Mac port; and text pasting is faster and more accurate on both the Mac and SDL. For 8DOS, DSK or WOZ files are supported. NIBs are also implemented but I'm...
by ThomH
Tue May 15, 2018 2:58 pm
Forum: Emulators
Topic: JOric
Replies: 84
Views: 4482

Re: JOric

(Of course, contacting MS would not hurt, if they care to answer I suspect they would confirm the hypothesis I just laid down here.) Not to mention that owning a licence does not necessarily mean owning a licence in perpetuity, or owning an assignable licence. Just as with PC-DOS, Microsoft may hav...
by ThomH
Mon May 14, 2018 11:35 pm
Forum: Emulators
Topic: JOric
Replies: 84
Views: 4482

Re: JOric

I can't speak as to the manuals but the Commodores identify themselves as running Commodore BASIC, and although the Apple version of Microsoft BASIC is often called 'Applesoft', nothing identifying is printed at all. So I'm not sure the absence of the word Microsoft necessarily means anything. It'd ...
by ThomH
Mon May 14, 2018 5:18 pm
Forum: Emulators
Topic: JOric
Replies: 84
Views: 4482

Re: JOric

I'm actually a bit confused about that second quote as it seems to imply that Tangerine was a company and that 'Oric' was another company rather than a product of Tangerine, which held a BASIC licence. The Register's version sounds a lot more plausible: 1983 isn't just the launch year of the Oric, i...
by ThomH
Wed May 09, 2018 3:02 pm
Forum: Games
Topic: Wolfenstein / DOOM for Oric : has this been done?
Replies: 19
Views: 1299

Re: Wolfenstein / DOOM for Oric : has this been done?

Here's a longer video of the same title by somebody other than me, not implicitly about proving that they've fixed a counter placement bug: [media]https://www.youtube.com/watch?v=J203nk_OxQs[/media] It was also available with completely different graphics for the Atari 400/800/etc, with the faster p...
by ThomH
Wed May 09, 2018 2:35 pm
Forum: Technical questions
Topic: 8DOS: overlay RAM control?
Replies: 6
Views: 449

Re: 8DOS: overlay RAM control?

I tried only 130 and, from memory, probably 210; neither seemed to proceed all the way back to the BASIC prompt. But it wasn't particularly systematic testing. I guess that most likely I've messed up my implementation of 0380–0383 as all DOSes to count down and then get stuck, so maybe they're inadv...
by ThomH
Wed May 09, 2018 4:05 am
Forum: Technical questions
Topic: 8DOS: overlay RAM control?
Replies: 6
Views: 449

Re: 8DOS: overlay RAM control?

Sorry, it's a gross digression, but having attempted to implement an emulation of the scheme as above, I see as per this video; the machine hangs at the end — I can wait indefinitely and that final frame will be unchanged: [media]https://youtu.be/rRGz0Uoo9QE[/media] So my relevant follow-up question...
by ThomH
Wed May 09, 2018 3:40 am
Forum: Operating systems
Topic: FastBoot/FastLoad on Pravetz 8D/Disk II
Replies: 35
Views: 2317

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

Well, the sneak preview gossip from my emulator is attached. I've not implemented any track skew, but still see the results as attached from your mapper.dsk so is it possible that Oricutron just doesn't preserve disk position when stepping tracks? i.e. each swing of the head magically resets the dis...
by ThomH
Tue May 08, 2018 2:16 pm
Forum: Emulators
Topic: JOric
Replies: 84
Views: 4482

Re: JOric

As yet I haven't published anything on Google Play. Not sure what the approval process involves. You make it sound like it has recently changed though. There are plenty of emulators on the Google Play store with system ROMs. Has something changed recently to make those less likely to be published? ...
by ThomH
Mon May 07, 2018 8:25 pm
Forum: Emulators
Topic: JOric
Replies: 84
Views: 4482

Re: JOric

Yeah, I've come at this whole thing from the slightly atypical direction of wanting to learn about TV standards first. So having that written, it wasn't too hard to plug the colour ROM in. I strongly suspect that the whole composite side of things is very uninteresting for most Oric users because th...
by ThomH
Fri May 04, 2018 6:25 pm
Forum: Emulators
Topic: JOric
Replies: 84
Views: 4482

Re: JOric

If you're asking me rather than dreamseal then I'll try to answer very briefly because this answer is not about JOric: yes. RGB output travels to the GPU as RGB. Composite output is constructed from the colour ROM and then handed off and decoded from there. And other CRT-emulation steps apply. The t...
by ThomH
Fri May 04, 2018 2:33 pm
Forum: Emulators
Topic: JOric
Replies: 84
Views: 4482

Re: JOric

I tend to adopt the mentality that each chip is sovereign, so as long as each has an interface with the same fidelity of information as the original pinout, it's sufficiently correct. That's why I care about using the actual colour ROM, because it's a knowable component, but haven't tried to deduce ...
by ThomH
Mon Apr 30, 2018 7:15 pm
Forum: Technical questions
Topic: Merging video output?
Replies: 68
Views: 13968

Re: Merging video output?

Tom: You should probably read back the entire thread :) I have to admit that I find it very hard to think of what would have a relevant response to "the only difficulty become to make the four cpus start exactly at the same time" given that it's also true that "the processors are not a problem at a...