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Monday, September 28

Geek

Daily News Stuff 27 September 2020

Short And Sweet Edition

Tech News

  • More leaks of Radeon 6000 specs from recent driver updates.  (WCCFTech)

    In raw numbers, Navy Flounder - the 6700 XT - looks to be 30% faster than the current 5700 XT, and Sienna Cichlid - the 6900 XT or whatever they choose to call it - to be 130% faster.  Dimgrey Cavefish will be the new low-end card and will probably run somewhat faster than the current RX 5700 (non-XT).

    These numbers put the 6900 XT at about 75% of the raw TFLOPs of the RTX 3080, but the RTX 3000 series increased TFLOPs more than it did game performance, so AMD looks to be in the 3080 ballpark.

    It could all be nonsense, but the numbers are plausible.  We already have full specs for the RDNA2 chips in the Xbox Series X and PlayStation 5, and these line up pretty well with those designs.


  • PyPy 7.3.2 now supports Python 3.7.  (MorePyPy)

    The 3.7 version is marked alpha, though it's considered stable outside of specific new Python 3.7 features.


  • The return of Fiber Channel: Kioxia (Toshiba) is sampling SSDs that plug directly into 25Gb Ethernet.  (Serve the Home)

    Each drive has dual Ethernet ports for redundancy.

    Fiber Channel itself is still around and according to Wikipedia can now hit speeds of 256Gbps, which is quite a lot.


  • San Francisco's Metropolitan Transport Commission is thinking of requiring tech workers to work from home.  (NBC News)

    "Preferably from a different state entirely," they added.  "California is fucked."


Disclaimer: We tried doing nothing, and now we're out of ideas.

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Saturday, September 26

Geek

Daily News Stuff 26 September 2020

Buried Ledes Edition

Tech News

  • Seagate Unveils CORTX Object Storage Software with Lyve Drive Rack Hardware Reference Design.  (AnandTech)

    I saw this yesterday and my brain glazed over.  Unfortunately that headline misses out certain key details, such as "open source", "GitHub", and "available now completely free for everybody".


  • Something is rotten in the state of RTX 3000 Land.  (Tom's Hardware)

    Several things, actually.  Apart from the fact that (a) the cards sold out immediately, (b) many of them went to scalpers running bots, and (c) some cards shipped in OEM packaging, which is to say, no packaging at all, we now find that (d) some models of third-party cards are randomly crashing.

    This appears to be due to the selection of - as Louis Rossman would say - cappa-sitters for power filtering.

    Here's all the details, as a reviewer tears apart about 2% of the worlds total stock of RTX 3000 cards to demonstrate the cappa-sitter issue.



    They are still hands down the fastest video cards you can buy...  That exist right now.  We'll see in a month how AMD responds.


  • Ruby 3.0 preview 1 is out.  (Ruby-lang)

    It has everything we expect from a new version of Ruby, such as an alternative assignment operator that works from left to right.  Because why not?


  • Will Dimgrey Cavefish please come to the white courtesy phone?  (Phoronix)

    The latest Linux kernel patches from AMD appear to confirm previous leaks about the upcoming Van Gogh low-power APUs (Zen 2, RDNA 2, DDR5) and identify a new GPU codenamed Dimgrey Cavefish, which slots in alongside Sienna Cichlid and Navy Flounder in AMD's exciting new game of Graphics Card or NPR Journalist.


  • Clippy has completed...  His?  Its?  Their corporate takeover of Twitter.  (The Verge)

    I see you are planning to use Twitter.  Do you really want to do that?


  • Google Maps is removing photos of Ayer's Rock.  (CNN)

    This is why we can't have nice things.


  • Been trying to think how our imaginary engineers could have used the cartridge port to upgrade the Imagine's graphics capabilities, the way some NES and SNES cartridges did.  Turns out you kind of can't, not without sticking a video port on the cartridge itself.

    The key design feature of the video controller is that it has two separate memory buses, so it's already twice as fast as the cartridge port; you can't push pixels through it fast enough to make a difference.  You have to put the new video controller and its memory and the video output circuitry all into a cartridge and then plug your monitor into that.

    So if you got a shiny limited-edition Imagine 1100A for Christmas in Earth 2's 1986, and then nine months later the Imagine 1200 showed up with twice the graphics performance, well, you were kind of stuck with it.


Manga Notes

Sousou no Frieren translates to Frieren at the Funeral.  Frieren is an elf; decades ago she was one of the heroes who defeated the Demon King and saved the world.  Now only two of the heroes remain; she has watched most of her companions die, not in battle but of old age, while she remains unchanged.

The demon army is on the move again, and Frieren is the only one still able to answer the call.  And it turns out that Sousou no Frieren also translates to Frieren of the Funeral, because she's all out of bubblegum.

It's quite good, both aspects of it.  And it runs weekly so you're not left hanging on forever.

http://ai.mee.nu/images/Frieren1.jpg?size=360x&q=95http://ai.mee.nu/images/Frieren2.jpg?size=360x&q=95


Disclaimer: Crikey, it's a rock.

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Geek

Daily News Stuff 25 September 2020

Super Secret Edition

Tech News

  • A decoder ring for Intel's 10nm process.  (AnandTech)

    Confused?  You're not alone.  Intel has changed the naming scheme for 10nm every time they've updated the process, and now pretends that the initial version of 10nm never existed.


  • Google wants to copy all of Apple's worst policies.  (Thurrott.com)

    Apple is embroiled in a growing war over their mandatory 30% App Store cut?  Perfect time for us to enforce our own 30% cut!

    Morons.


  • A look at ASRock's new entry-level Epyc server.  (Serve the Home)

    It only supports 64 cores, 1TB of RAM, and eleven PCIe 4.0 NVMe drives, so if you're looking for high performance or scalability....  Yeah, that's pretty good for 1U.  Dual 10GBaseT built in, plus a standard network upgrade thingy that they tested with a dual 25Gb module, plus one full-size PCIe 4.0 x16 slot.

    The ten 2.5" bays accept either NVMe or SATA drives, which is a nice touch.


Disclaimer: Nope, still blaargh.

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Friday, September 25

Geek

Daily News Stuff 24 September 2020

Never Mind The Quality Feel The Width Edition

Tech News

Disclaimer: Blaargh.

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Thursday, September 24

Geek

Daily News Stuff 23 September 2020

Ugh Blockchain Edition

Tech News

  • Ugh.  One of those days.  My biggest achievement was managing to sign in to Patreon, and I really didn't do anything to fix that.  Also Patreon still sucks, but unfortunately good people use it.


  • The Samsung 980 Pro is TLC but still good.  (AnandTech)

    Samsung's PM1725 server drive is included in the benchmarks here.  That's what's on the new server, and it doesn't compare well against the newer consumer drives.  On the other hand, for the one benchmark that I can compare directly - sequential reads on an unfragmented drive - I'm seeing 50% better performance than they do here.

    The PM1725 is optimised for long life, though; it supports 10x the total number of updates of the 980 Pro.


  • Intel has some new 10nm Atoms for embedded use.  (AnandTech)

    The 10nm 4-core CPU die plus its 14nm I/O die total 120mm2.  AMD's 8-core Ryzen APU is 150mm2, uses only slightly more power, and is at least four times as fast.


  • Speaking of AMD they are preparing a Zen 3 APU with Navi 2 graphics on TSMC's 6nm process unless they aren't.  (WCCFTech)

    Such a chip won't show up until at least late 2021.  We haven't seen 7nm Zen 3 yet. 

    It will support DDR5 RAM and PCIe 4.0.


  • Microsoft has acquired exclusive rights to the GPT-3 language model.  (Science Times)

    The code is open source, but the trained data model that produced fake Atlantic think-pieces and whatnot is proprietary.  It will be available on Azure.


Disclaimer: Not that there's any great demand for more Atlantic think-pieces, fake or otherwise.

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Wednesday, September 23

Geek

Daily News Stuff 22 September 2020

Ugh Browsers Proxy Servers Edition

Tech News

  • There's another update out for Chrome already.  Does it fix anything?  It does not.

    Bah.  I'll test a workaround for this mess after I post the news stuff.

    Update: The problem was ENTIRELY DIFFERENT TO WHAT I THOUGHT IT WAS AND NOT A BROWSER ISSUE AT ALL.

    Also, fixed.

    Basically, Caddy (the proxy server we use) failed to automatically renew some of our SSL certificates.  Don't know why exactly, except that it's been running for several months without a restart.

    We've been running it for a couple of years at my day job without this happening, but we push config changes every couple of weeks so it never runs that long without a reload.

    Common JavaScript files for mee.nu live on a shared domain and are always loaded over HTTPS.  That stopped working a couple of days ago.  I'm kind of impressed by how few things broke.


  • Arm has announced two new server cores.  (AnandTech)

    The N2 - codename Perseus - offers a 40% IPC improvement over the N1 core that Amazon is using in its Graviton 2 server platform.

    That's quite a lot.  That performance will also be coming to the A79 or whatever they choose to call their next mobile core.  N2 is due out next year.

    The V1 on the other hand is their new performance core.  Yes, the 40% IPC improvement over their current best offering is now their mid-range core.

    V1 - codename Zeus - promises 50% better IPC than N1 at the same clock speed, plus better clock speeds, and double the floating-point performance of the N2.  Arm estimate overall V1 will be around 20% faster than N2.  And it's available to license today.  

    This is the core used by the SiPearl Rhea that I mentioned previously.

    The V1 is a maximum-performance damn-the-power-consumption design and will not be coming to mobile devices, but it's what Arm needs if they are to compete with AMD in the server space.

    Serve the Home has more.


  • Microsoft is buying Bethesda.  (Thurrott.com)

    Makers of the bad Fallout games.

    It's a shame Microsoft wasn't in the mood when Bioware was on the market.


  • Planet K2-315b has a surface temperature of around 180C (350C) and is "likely not habitable".  (CNet)

    It also orbits its star, EPIC 249631677, in just 3.14 days.

    EPIC 249631677 - let's call it Ted - is 57 parsecs from Earth and not exactly suitable for daytrips anyway.


  • Memory price trends, 1957-2020.  (JCM)

    Interesting to note that early on, vacuum tubes were cheaper than transistors.  I'm guessing though that even in the 50s transistors were a lot more reliable.


  • Okay, since I have that weird comment thing fixed, time to think about game programming on the Imagine.

    Let's take Civilisation - not the popular game, that's spelled with a Z.

    The Pangea tileset that inspired this is 16x16, perfect for the Imagine's tilemap mode.  Load the tiles into RAM once, create a map - a 100x80 world map is just 8k - use sprites for the units, and we're good to go.

    Except...  Not so fast.  Look at this example.

    http://ai.mee.nu/images/ImagineCivimap.gif

    We don't just have the background tiles.  The background tiles are overlaid by terrain and vegetation, rivers, roads, and railroads.  Rivers over terrain can be overlaid by road and railroad bridges. Resources and resource icons overlay terrain and vegetation.  Water is animated.  And over all that there's a rather literal fog of war for unexplored territory.

    Handling all that would require a separate 32-colour full-resolution overlay playfield, and the original Imagine 1000 can't quite manage that; it runs out of clock cycles to access everything.

    So instead it has to be done in pixel mode, and that eats 64k of RAM on top of all the tiles and sprites that need to be loaded.

    There's a reason Civilization - the one with the Z - didn't come out in 1983.

    Looking at the tileset, all the animations for all the units combined are only 40k.  But with 64k assigned to the pixel map, we only have 192k for all the tiles, sprites, code, and data combined.  In virtual 1983, 40k is a lot.

    This is where we say things like "combat animations require the optional 128k RAM expansion cartridge ($89.95)".


  • Ram Packs for Everyone!

    Figured out a two-chip solution that makes the Imagine about eleventeen times better.

    So, the design has three main chips: The CPU, the DSP, which we're going to completely ignore, and the video controller.

    There's 128k of system RAM - called shared RAM for reasons we'll get to in a moment - and 128k of video RAM.

    The video controller has two full buses, and can directly access both video RAM and system RAM.  It was ostensibly designed as a standalone controller for graphics terminals, needing just a suitable UART and ROMs for the code and fonts; one bus for video data and the other bus for everything else.

    It can also use both memory buses for video data.  This lets the Imagine display two playfields at 480x270 in 32 colours, at the cost of absolutely squashing CPU performance.

    While scanning through 1980s Toshiba component databooks looking for memory timing information, I noted in passing that there was a standard 74LS part for a 10-bit three-state bus transceiver.*  Caught my attention because I was looking up stuff for a fantasy 10-bit computer.

    Now, what happens if we take two of those chips, and put them on the data and address buses, so that on one side is the video controller and the two built-in memory banks, and on the other side is everything else?

    Well, if you don't have a RAM cartridge, not much.  The CPU is now free to access ROM on cycles when the video controller is accessing shared RAM, but that's a minor win because the built-in Basic is a compiler anyway.

    If you do have a RAM cartridge, though, that means the CPU can run at full speed even while the video controller is using all the bandwidth of both internal memory buses.  Instead of just giving you 128k of system RAM, it doubles the graphics capabilities of the system.  We can even do a tweak and split sprites across the buses so that they can each be 20 pixels wide instead of just 10.

    With a later 256k or 512k RAM cartridge things get even better.

    So yes, those two chips go in.  

    * The original part was a 74LS861, I think; that's the modern equivalent.


Apropos of Nothing

http://ai.mee.nu/images/NotSoMuch.png


Disclaimer: Fucking Elasticsearch.  28,000 records total.  4.5GHz CPU.  128GB RAM.  Seven second search times.

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Monday, September 21

Geek

Daily News Stuff 21 September 2020

The Clocks Were Striking Thirteen Edition

Tech News

  • The new version of Chrome has fucked up the comments.  I'll try to fix that tomorrow.  I can at least work around it.


  • China is at war with everyone.  (ABC)

    Including, of course, the Chinese people themselves.

    This is the Australian ABC reporting the story, not the US ABC, proving that a bunch of godless Lenin-worshippers suckling on the public teat for sixty years are more honest than the American mainstream media.


  • The US Air Force has designed, built, and flown a new fighter jet prototype.  (Defense News)

    In under a year.


  • I've done the instruction code layout for the Mirage M1100 CPU - the 11-bit variant.  It was instructive; for example there is now only one type of address postbyte, because one extra bit was enough to combine the indexed and extended register addressing modes.  For regular opcodes the extra bit defines the operand size - byte or word - and thus switches between 11-bit registers A, B, C, and D, and 22-bit W, X, Y, and Z.

    That freed up enough code pages that I could add in instructions to add or subtract 11-bit values to 22-bit registers, with and without carry.

    It also tells me that the best version of this will be the 13-bit one.  Originally that was going to be a weird dual-issue stack-based system, like an Analog Devices SHARC on crack.



    I might still do that version, but it would require an entirely new compiler and would generally be a pain in the bum.  The sane version will come first, but I'll need a new name for it.  (Pokes thesaurus.com.)  The Vision, that's just the ticket.


  • Rule 1 briefly suspended.  (Ars Technica)

    Rule 1 is of course never read the comments but that doesn't apply on personal blogs (mostly) or on Ars Technica's Rocket Report posts.

    Still on display though is the usual Ars Technica trait of aggressively downvoting anything you disagree with; the only difference here is that the point of disagreement isn't politics.

    Also, of course South Australia has a town with the most offensive name possible.


  • From watching gameplay videos on YouTube, I have a whole bunch of minimum specs for these systems, most of which I fortunately already had in mind.

    • 32 colours selectable from 512.  16 colours just doesn't quite do it.  64 is better.  More than 64 starts to make it too easy, and the results look noticeably different.

    • 480x270 resolution.  Yes, this is mostly to upscale nicely to a 1080p monitor, but also because 320x200 isn't actually very good and looks like crap on a large screen.

    • 4-voice music and 2-voice sound effects.  Can be stereo, mono, or split channels like the Amiga.  Music can be wavetable or PCM, or PSG or FM synthesis if the number of voices is increased (two PSG voices can produce one FM voice, for a start).  The Sharp X68000 which we heard in action with Dragon Spirit had 8-channel FM synthesis and sounded pretty good.

    • Some way to do parallax scrolling.  Dual playfields, a really fast blitter, a ton of sprites, tile rotation, something.

    • Hardware smooth scrolling in both X and Y.  Scrolling by a character at a time on an arcade-style game looks like poo.

    • Multi-colour sprites.  Four, or better, eight colours per sprite.  And at least eight of them.

    • So basically an Amiga.  Huh.


  • So in this parallel and much nicer reality, these systems came out one after another starting in 1983 with the 10-bit Imagine, followed in 1984 by the 11-bit Mirage, the 12-bit business-oriented Dream in 1985, then the 13-bit Vision and the 9-bit Phantom in 1986.

    Before 1983 you couldn't meet the specs above at a sane price; by the mid-90s systems were way more complex than anything I want to emulate.  The SNES came out in 1990 and already the video chip in that is Nyarlathotep in silicon form.

    My window of interest essentially starts in 1983 with the Fujitsu FM-7 and ends in 1992 with the Sharp X68000 Compact, the last model with an original-generation 68000.  But that's plenty of room to play around in.


Twelve Hours Worth of Chiptunes Music Video of the Day



Via the X68000's Yamaha OPM 8-channel FM synthesizer.  Don't say I never take you anywhere.


Disclaimer: Ah, there's the music from Eco.  Wait, stop changing scenes and making it change music tracks, go back to-  Ah, thanks.  Wait, you did it again, stop that!

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Sunday, September 20

Geek

Daily News Stuff 20 September 2020

Dundundundundun Edition

Tech News

  • Had the soundtrack to a side-scrolling shooter from the Amiga running through my head this evening.  Could not even remember the names of any of the side-scrolling shooters I played back then.  So I asked YouTube.

    It was Menace.



    That track, the one that plays right at the start, that's what I had stuck in my head.

    If you didn't play this game on the Amiga, though, you would have had completely different memories of it.  Mostly sad ones.



    Menace was created by DMA Design, who also created Lemmings and subsequently a little title named Race'n'Chase.

    Better known today as Grand Theft Auto.


  • Just watching that video I can see the Amiga is using:

      •  Dual-playfield mode (for parallax scrolling).
      •  Hardware sprites.
      •  Blitter objects.
      •  Copper (display list) programming to change the video mode on the fly.
      •  Four-channel PCM audio.  Well, I can't see that one.

    The other three systems have none of those features, and as a result those ports of the game all kind of suck.


  • Went out to lunch today with my brother and sister-in-law, who live locally.  Most things were back to normal, the shopping mall was bustling, and the asian fusion restaurant that does the amazing gluten-free pad siew was still in business and open.

    The Apple store, on the other hand, had a queue where they took your details, sanitised your hands, and gave you a mask to wear inside.  We did not go into the Apple store.


  • Behind every warning label lies a story.  The same is likely true of this motherboard with 20 USB ports.  (Tom's Hardware)

    I'm not sure I want to hear it though.


  • Spider Man, Spider Man, does whatever a 105GB download can.  (WCCFTech)

    That's only approximately one million Imagine 1000 ROM cartridges.


  • Apple has reportedly booked 100% of TSMC's 5nm production capacity.  (ExtremeTech)

    To be fair, Apple, or rather the fools who buy Apple's overpriced toys (cough ignore the retina iMac to my left cough) paid for TSMC's massive CAPEX that enabled the 5nm process in the first place.


  • If at first you don't succeed, try, try, try, try, try, try, try, try, try, try, try, try, try, try, try, try, try, try, try, try, try, try, try, try, try, try, try, try, try, try, try, try, try, try, try, try, try, try again.  (Phoronix)

    Intel have submitted patches to include support for their secure enclave in Linux.  For the 38th time.


  • It took me about two minutes to identify Menace on YouTube from just a half-remembered theme tune.  Find a video of the top ten Amiga side-scrolling shooters and flip through them going nope, nope, nope, cool but nope, THERE, THAT'S IT!

    Some people take a bit longer to find the game they're nostalgic for. (Break Into Chat)

    Like, seven years longer.


  • Russia has announced plans to explore Venus.  (EuroNews)

    And to be fair, Russia's track record with its Venus probes is as good as its record with its Mars missions is bad.


  • I've moved the launch of the Mirage (the 11 bit architecture in my emulator) back to 1984 and downgraded the hardware to match.

    It now has specs very similar to the original Imagine from 1983, but instead of 128k of VRAM, has two video controller chips each with 64k.  And the floppy drive capacity will be 900k, since double-sided 3.5" drives came out in 1984.

    It has just two graphics modes, compared to approximately seventeen thousand on the Imagine, but they are really nice graphics modes:

    Mode 1: 480x270 in 32 colours or 240x270 in 1024 colours, switchable on a two-pixel boundary.
    Mode 2: 480x270 in 32 colours, or 960x270 in 4 colours with 4 palettes, switchable on a two-pixel boundary.

    Update: Three modes.  When I figured out Mode 3, I realised there's no way they wouldn't have pushed it in somehow.

    Mode 3: 320x270 in 256 colours with 4 palettes, switchable on an eight-pixel boundary.

    And you can overlay a Mode 2 playfield on a Mode 3 playfield, and modulate the colours on one-third pixel boundaries.

    The pixel data from the two VDCs is XOR'd and fed into a 1024x12 external palette RAM.  (I looked it up and suitable chips were indeed available in 1984, though I'm not sure how much they cost.)

    By default VDC1 would output the low 5 bits and VDC2 the top 5 bits of the final pixel value, so they combine independently to provide one of 1024 colours. And that means you can precisely define transparency, translucency, and shadow effects, or just output 480x270 in 1024 colours, or anything else that is not actually mathematically impossible.

    If you output two 1024-colour low-resolution playfields, though, things will get weird.  I might not bother to fix that.  Sometimes weird is good.

    I think the 11th bit in the instruction encoding will be used as a size bit - byte or word.  That's a really simple update to the 10-bit architecture but a very nice one; it makes the four index registers (WXYZ) true general-purpose registers. On the Imagine they can be used for arithmetic via LEA, and just gained shift operations in the weekend opcode cleanup, but they don't have the usual AND/OR/XOR, or even subtraction.  And while LEA can do A=B+C addition, by design it doesn't set the carry bit and can't be used for extended precision arithmetic.


Disclaimer: Me listening to 30-year-old Amiga music: Wow, eight-bit PCM audio was pretty rough.  Me listening to 30-year-old Atari, PC, and C64 music: Oh, right.

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Saturday, September 19

Geek

Daily News Stuff 19 September 2020

Pieces Of Ten Edition

Tech News

  • Now if you want to take some pictures of the fascinating witches who put the scintillating stitches in the britches of the boys who put the powder on the noses of the faces of the ladies of the court of King Caractacus you're too late!  (TechReport)

    Because they've just sold out.

    They being the RTX3080 and both models of the PlayStation 5.


  • The WeChat and TikTok bans kick in on Sunday.  (Tom's Hardware)

    Good.


  • VueJS has hit 3.0.0.  (GitHub)

    I haven't done anything real in it, but it does seem to be the least sucky of the major JavaScript frameworks.


  • Based solely on watching videos of Dragon Spirit I have retroactively determined that the Imagine included a cartridge slot.  It could take ROM cartridges mapping up to 128k of address space (plus optional bank switching) or a RAM cartridge for an additional 128k of system RAM.

    The system assigns a single 10-bit bank register to the cartridge port, and leaves it up to the cartridge hardware to determine how to deal with it, but in theory it could support 1024 128k banks for a total of 128M of ROM (or indeed RAM).


  • That means that the big feature of the Imagine 1100 wasn't expandable RAM, but that it came with 128k of system RAM and 256k of video RAM.  You could use the same 128k RAM cartridge to bring system RAM up to 256k, but video RAM wasn't expandable.

    The 1000 and 1100 used page mode RAM, while the 1200 used faster nibble mode RAM, so RAM expansion cartridges weren't perfectly compatible.  They did work, but ran slower than system-specific models.


  • In other fantasy computer news I needed exactly one and a half bits to add a whole new exciting family of addressing modes to the Imagine and clean up an untidy corner of the instruction set.

    I found them.

    Now PC relative addressing only has a range of -128 to +127* instead of -512 to +511, but every instruction has access to special hardware registers, alternate register banks, and on-chip RAM, if they exist in this particular implementation of the CPU.

    So, for example, the DSP variants define AL and AR as left and right audio accumulators, and multiple banks for ABCD and WXYZ, but there was no standard encoding for accessing those registers outside of the specific MAC and BANK instructions.  The OUT $01E, AR to output a calculated sample to the right audio DAC had to be custom crafted into the DSP.

    This new method also encodes 10-to-20-bit conversions like LD A, WL which previously was only possible via LD AB, W - and even that was a special instruction distinct from standard LD.

    These methods require a two-byte instruction encoding, but the second byte is similar to the format used for indexed addressing, rather than a big nasty ad hoc mess.

    This is also how supervisor mode (on variants with a supervisor mode) access the segment and address extension registers (on variants with segment and address extension registers), and how multi-threaded versions spin up and synchronise threads.  None of that will be present in the initial version, but it's all defined so I won't trip over it later.

    * Unless you use indexed mode with P + immediate offset, which has a full 10-bit or 20-bit range but uses one or two extra bytes.


Retro Gameplay Video of the Day



Quick precis: MSX1 bad.  MSX2 pretty good actually.  Also, most MSX systems apparently had two cartridge slots.  Hmm.



Bonus Retro Gameplay Video of the Day



This is Dragon Spirit captured from original arcade hardware.  The video isn't as sharp as from an emulator, but it's the real deal.

Listening to the sound, I'm pretty sure it's using three music voices plus two voices for sound effects.  There are a number of places where you'd expect a fourth instrument to come in, and it never does.

The Imagine can reasonably do five voice wavetable synth at 3MHz, and I've assigned eight sets of registers to the DSP so the other three sets can be used for sound effects, which require less complicated processing.  (The hypothetical Imagine 1200 from 1987 doubles everything, so 10 wavetable voices and 16 sets of audio registers.)

I really like the first couple of tracks here.  Super catchy.


Extra Bonus Retro Gameplay Videos of the Day

Last ones, I swear.

The first is Dragon Spirit on an MSX2 system - 3.5MHz Z80A, 256k of system RAM (though I believe it ran in 64k), and 128k of video RAM.

The second is Dragon Spirit on a Sharp X68000 - 10MHz 68000, 1M system RAM, 512k bitmap video RAM, 512k tile video RAM, and 32k sprite RAM.




The X68000 version definitely looks better, but the MSX system isn't bad at all.  I believe this was a disk-based game and not a cartridge, so that's actually running from just 64k of RAM.  There are some odd hitches in the music on the MSX that aren't present on the X68000, possibly because it had an 8 voice sound chip rather than just 3.


Disclaimer: Bleep bloop.

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Geek

Daily News Stuff 18 September 2020

7-4+2=1 Edition

Tech News


Atari 800XL Gameplay Video of the Day



Some of these games are really impressive for 8-bit hardware dating to 1979.  But there is a reason I'm targeting the Imagine at a notch above most of the real 8-bit systems, a little above even the MSX2 or the FM77.

There are a ton of MSX gameplay videos on YouTube, by the way.  The original MSX was rubbish, but the MSX2 wasn't bad.  People have even got it to run a multi-tasking GUI with TCP/IP.

A lot of the MSX2 games are still pretty bad, but some look quite good, like Dragon Spirit.  Here's the MSX2 version:



This seems to be the original arcade version, emulated via MAME.  It's certainly better looking than the MSX2 could manage.



Disclaimer: Not that I plan to spend the entire weekend watching them.  Not the entire weekend.

Posted by: Pixy Misa at 12:30 AM | Comments (32) | Add Comment | Trackbacks (Suck)
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