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Tested in [desktop] Safari 13.1.2 (an up-to-date version), the following worked:

• jsatom;
• Tiny Emulators;
• virtualkc;
• Elk JS; and
• JSBeeb.

So, assuming I didn't miss any, only HTeMuLator failed. It worked in Firefox so I'm pretty sure Safari is the relevant factor.

Update again: the first round of Qt and Snap bug reports has thrown light on some extreme flaws but I'm hoping that everything severe is now fixed. So if you've tried to use the Qt build before via either route to availability, it's definitely worth updating. Binaries via Snap ; tagged source from G...

Suggested updates for the lead post: b2 is available as a prebuilt Linux binary via Snap ; as is Clock Signal ; also, given that Clock Signal emulates only the Electron from Acorn's lot, could it please just be listed as an Electron emulator?; alternatively, Tiny Emus is much, much broader in scope ...

Regarding SDL using outdated APIs, b2 is using an outdated version of SDL - I have my own fork, because of a long story , which is now rather out of date. I aim to do something about this at some point(tm), arranging things so that b2 can use unmodifed latest SDL on all platforms, and hopefully thi...

After going through Apple's "control + click, cancel, control + click, oh look, you now get the option to run the program, run program" rigmarole, b2 starts up and runs as expected. OK, I don't know enough to test everything, but it runs the program I'm developing so that's enough for me at this st...

Minor update: Clock Signal's Snap listing now possibly works.

Snaps are not Ubuntu-specific but this also means that if you're a Ubuntu user then Clock Signal should now be listed in the 'Ubuntu Software' storefront. Hopefully. I'm not good at this stuff.

I think security professionals will agree that you don’t need quote marks. But like any software security there are ways around them, either through bugs or human ingenuity, which Apple fix as quickly as they can. Right — heightened is correct, resolved unambiguously wouldn't be. Sandboxing moves y...

If people are writing machine code and handling floats, do they write their own routines for e.g. multiplication from scratch, or do they call built-in routines that are already as fast as can be? I'd be interested to hear of anyone who is using floats from machine code. I thought it was more usual...

As an aside, supposing it ever becomes a bottleneck, I once checked out the MOS routines versus completely hand-crafted line drawing on an Electron. On that machine the processor accesses ROM more quickly than RAM so if you wanted to reproduce the full swathe of MOS functionality then you'd be at qu...

I don't know what the quotation marks are meant to imply, but to confirm Apple's model with respect to file access: Apps which have opted in for neither the sandbox nor the hardened runtime still act exactly as they always did, other than that the user has to jump through more hoops to be permitted ...

I've got it working in VMware/Ubuntu! I'm running the Electron emulator part and noticed that the screen is quite wobbly. It doesn't matter if I select RGB, CompositeColour or CompositeMonochrome. Is that a feature of the interlaced PAL signal? Almost certainly; there's no explicit deinterlacing st...

It is on the wikipedia list... it is the 16 bit CRC with normal polynomial 0x1021. Thanks. AIUI, it's initialised with &0000 not &FFFF, so it's not the CCITT CRC-16. Closer to the XMODEM CRC16, though perhaps with a permutation of the byte/bit ordering. To expand on this, from browsing the definiti...

beebjit and MAME do. I'd be surprised if there were not others. Yeah, Clock Signal too — the sector image + FDC response-style formats are sometimes a real hassle to support as a result. Thankfully mid-level stream formats are pretty popular on a bunch of platforms; off the top of my head there's G...

Anyway the real adoption problem with stream or cells based formats (SCP, KF RAW, HFE...) are not the formats documentations or whatever but the fact that most emulators don't really emulate the FDC. beebjit and MAME do. I'd be surprised if there were not others. Yeah, Clock Signal too — the sector...

Picking up on this late, but John Morris created the WOZ disk image file format for Apple IIs; in order properly to advocate on how support should be implemented he's written a bit on the MC3470 here, in the 'Freaking Out Like a MC3470' section . Specifically: The MC3470 chip is the heart of the App...

Coeus wrote: ↑

Tue Jun 30, 2020 11:46 am

Anyway, that says it is revision 1.1. Is that the latest, other than 3, i.e. was there no revision 2?

Nothing after v1.1 is documented, and the only there thing I've heard of people using is v3. So my guess would be that there's no revision 2.

Hi Thomas, thanks again for your great talk! I really, really want to experiment with CLK but I can't figure out if it is possible (and easy) to build a Windows version? Alas, I don't have a good answer for that question. I haven't used Windows at home for 17 years, or at work for 12. That said, I'...

Clock Signal is: an emulator of multiple systems, including the Acorn Electron; that tries to be a little more rigorous than the average in audio and video output — raw audio is sampled at the machine's native rate then lowpass filtered and resampled to whatever your machine supports, composite vid...

Also, HFEv1 has been supported by Clock Signal, an Electron emulator, for a few years now. I intend to look at HFEv3 soon, due to its momentum around here.

Yeah, my argument was: original author of file format advocates against HFE as an emulator file format; the format has already changed substantially since the only time it was documented; the author makes no promises whatsoever about future stability; and the only code offered locks out three-quart...

I find ElectrEM a bit buggy. ElectrEM hasn’t been updated for a number of years and doesn’t work well with Windows 10. Elkulator works better on Windows 10. It also can be configured for either DFS or ADFS file systems. With ElectrEm you can just import the text file directly as BASIC — the emulato...

Where can I read an overview / specification of stream HFE? Is it supported by Gotek + FF? I'm not against a change of tack here but I've been studying all of the particularly advanced BBC on-disc copy protections and HFEv3 is continuing to hold up as a really robust match. I'd have to defer to the...

Hi, Working with @billcarr2005, I'm starting to convert his large library of FSD protected beeb disc files to HFE files. Why HFE? 1) HFEv3 files are capable of accurately representing all currently-known copy protection methods used on the beeb. I have designed the HFE (v1/v2/v3) for the H xC F lop...

I dispute this claim. :shock: :shock: :shock: Could you try this one as well? https://stardot.org.uk/forums/viewtopic.php?f=64&t=18431 Alas something seems to be off with that; I guess I don't quite have one of my interrupts properly placed horizontally. The ball bounces up and down properly, and t...

tricky wrote: ↑

Fri Jun 12, 2020 7:46 am

Do you get any CPU in MODE 0-2 while the beam is off-screen per scanline?

Yes — on lines with pixels you get 1Mhz access to RAM in the border region, i.e. 24 cycles/line.

That looks really cool. I'm not on Twitter, but will subscribe to this thread. Re: memory footprint, I've heard other modern retro coders raving about LZ4 compression; e.g. here's an Apple II implementation that claims to be able to decompress full Apple II frames at 4.3 fps. So that's a 1Mhz 6502 d...

part of the FIR filtering will utilise Apple's Accelerate framework for vector operations Sorry for the plug, but if you're into FIR filters (particularly polyphase filters for scaling or phase-shifting) you might be interested in another of my BBC BASIC programs (it's the only language I know well...

Thanks Thomas, for your information about CLK, I'd not come across your emulator before - there are a lot around. I will have to try it out it looks to have an interesting approach! I'll try and get a look next week at it - when the child is back at school and I get some thinking time. Did you use ...

It will NOT work 100% correctly on any existing Electron emulator; only on the real machine! I dispute this claim. Screenshot 2020-06-11 at 09.41.39.png ... and since I haven't changed anything in the timing on the Electron part of my emulator in a few years, I backdate that to 2019. All I did was ...

15 or so years later it became possible to achieve the same functionality purely in software on a (fast) PC, which made it much easier to manufacture and more flexible. The challenge was to get as close as possible to the timing predictability that the hardware implementation had achieved. Locking ...