On 12 July 2016 at 21:41, Swift Griggs <swiftgriggs at gmail.com> wrote: Well I'm hoping so. There was an update a couple of days ago on the Facebook page, where they said: "This resulted in the current price of the Spectrum Next to be around ?160 including the accelerator board" "The original plan of starting the campaign on Kickstarter in June is now pushed back around a couple of months" So keep alert! Steve

On Tue, 12 Jul 2016, Eric Christopherson wrote: That project looks amazing! Does anyone know how far along they are? The web page is dated 2015, but that probably doesn't mean much. However, it's clear they aren't shipping, yet. One thing that I notice right away about that picture is how bright white that case is! Even with retr0brite, that's hard to do... helps that it's brand-new, though. -Swift

On Tue, 12 Jul 2016, Rod Smallwood wrote: As a hobbyist I've made a few tee-shirts, bags, and other items using a real silk screen, transparencies, photo resist emulsion, PVC inks, and a heat gun. I've done primitive "trap color" using registration marks, but never "process color" (too hard without a 4 screens and better gear). Is the process you use similar? I'm only asking because I'm curious. Also, just out of curiosity, what kind of color process can you do on a circuit board or side panel ? The most complicated thing I've seen is CMYK process-color done with water based inks and fancy super-tight registration. The results (not by me) were really awesome, but I'm guessing that kind of thing isn't done the same way on non-fabric materials (perhaps PVC inks work, though). -Swift

I haven't heard of these projects. Do you have a larger list of projects that exist?

that I found a list on the MIST site https://github.com/mist-devel/mist-board/wiki/FPGA-Projects https://github.com/mist-devel/mist-board/wiki/TheBoard which is a project to let you run multiple emulations on a single board... There is also another IBM1130 emulation which is functional rather than cycle accurate... http://ibm1130.org/party/v06 Dave micro?

But that's true of much vintage computing. Original CoCo III and even Speccy's sell well on E-Bay. The modern replacements have the advantage they can use a "modern" VGA display, SD-Card for data not slow cassette tape. Dave

I was being sarcastic. VGA is now becoming obsolete, modern screens are starting to drop it for DVI/HDMI .... ... I keep some "legacy" 3:3 flat panel LCD displays for the same reason... Dave

It's pretty cool seeing what people are doing out there. I like when people replicate things that are super rare -- like the Mark-8, SCELBI, etc. And it's definitely cool to see projects like the Altair clone, with its big empty case, all the hardware being emulated by a tiny little replacement inside. I think the Amiga project is neat, although personally I'm not sure I'd find a need for one. The thing about the Amiga was its wow factor -- I remember walking into Compucentre (Canadian chain) in the mid-80s.. and there's all the computers from 8 bit heaven and their 16 color graphics (if you were lucky).. and then there's this one computer on a pedestal featuring a totally real jungle cat prowling onscreen. It just blew the doors off everything else there, and I would go wanting for one for 20 years afterward (now I have 5 :)). Not sure a replica can revive *that*.

I have kind of a counter around my 'office' and I've laid out stuff on top of and under it (and even stuff on top of the stuff). I have one 'work' desk where I set up a machine or two and play. My Digital Group Z80 has been occupying that spot for months -- just too much fun to play with. But my Amiga 2000 is right next to it. I remember after seeing that Amiga 2000 at the store trying desperately to convince my Dad to buy one. I don't remember what the exact price point was but it was up there, and his concern was compatibility with work. An IBM loyalist, he went from PCjr to PC to AT to PS/2. I do remember knowing that they had the XT emulation board available for the Amiga and trying that angle with him to no avail. Later on as a consolation he acquiesced to putting in a (then) very expensive 2400 baud modem into our PS/2 so I could BBS. My question about the FPGA Amigas is can you not just emulate pretty much anything on a PC these days? I never tried Amiga emulation (if I have the real thing I always go to that). Not sure how much the emulators can handle. -----Original Message----- From: cctalk [mailto:cctalk-bounces at classiccmp.org] On Behalf Of Swift Griggs Sent: Thursday, July 14, 2016 7:50 AM To: General Discussion: On-Topic and Off-Topic Posts <cctalk at classiccmp.org> Subject: RE: Reproduction micros On Wed, 13 Jul 2016, Brad H wrote: I have an Amiga 3000 (my personal favorite), but I have limited space so I can only have about two "classic" systems set up at once (and those are usually SGI machines in the retro-spots-of-active-honor). I'm not one of those types who has a personal warehouse with loads of old gear stacked on huge shelves. So, I find that I spend a lot more time with a MIST FPGA Amiga than my real 3000. The main reason being that since it can use VGA + USB, it's small, and it's super easy to put on a KVM make it attractive in my case. Plus it can emulate so many micros, I get more time with them. I totally agree. I'm not a huge fan of Workbench, but the Amiga hardware and the way folks exploited it in games, demos, and applications was the thing that impressed me. All those custom chips doing interesting things (music and graphics - there was no bean-counting-co-processor thankfully) while at the time my impression of PeeCees was that they just bottleneck'd everything through one pathetically slow CPU with brain-damaged memory management and then wanted to brag in a dull magazine about mind-numbing things like how fast you could get a spreadsheet done or reconcile accounts payable for your boss... ie, reeeeal inspiring stuff to a 14 year old (*yawn*). I see things a bit differently, now, (I actually think DOS and x86 is cooler now than I did back in the day) but that's how I felt as a teen. Of course the x86 today just feels like it's so complex that the actual microcode you "get" to access & play with isn't really reflecting what's going on inside. It's just some shared fiction while the CPU really does super-complex optimizations way beyond what any one person can really understand anymore. It's also why I haven't curiously disassembled any C code in probably a decade. I realized the compiler could always do a better job and use instructions or features I didn't even know existed. Perhaps, I think that way because I'm not a specialized EE staring at chip lithography all day. However, others have made the point more elegantly before on the list. I had nearly the same experience at a chain here in the states called "Electronics Boutique". They'd have a couple of PeeCees running demos and facing out the storefront. Your eyes would always been drawn to the Amiga running a Dragon's Lair or Space Ace demo (or something else awesome). I remember being in the store talking to the staff and people walking in to get a PeeCee and walking out with an Amiga because the kids were so impressed with the games and graphics etc... Also, I've heard versions of this same story from at least three other people. It seems to be a very common experience. It definitely whet my appetite for Amigas, too. However, at the time $$$ was a big problem for me and my family. So, it really wasn't until they were started to become quite obsolete that I finally got to own one. By that time, I was into UNIX and so it was already just a "retro curiosity" but one I still enjoy. I do wish I'd got the chance to use Amigas to do something "real" when they were state of the art. That or I wish I'd had an A500 the day they hit the shelves and had all the cool games. I'm sure that would have been a lot of fun. -Swift

On 7/14/2016 8:50 AM, Swift Griggs wrote: I had hopes on the Amiga until they came out with the 2000*. Ben. * Lets add a brain dead cpu and run DOS.

On Thu, Jul 14, 2016 at 01:03:31PM -0600, ben wrote: [...] The A2088 was an add-in option. Back in the day, only one of my A2000-owning friends had a bridgecard. I was given a demo, and it was rather clunky. The main compelling feature of the A2000 was the built-in hard disk. Commodore UK also released the A1500 which was an A2000 without hard disk but with an extra floppy drive, i.e. the same spec as a typical A500 gaming rig. It apparently flew off the shelves, although I'm not sure why given it cost somewhat more than the A500 equivalent.

On Sat, 16 Jul 2016, Peter Corlett wrote: The A2000 did *not* have a built-in hard disk, that was the A3000. The A2000 was just an "updated" A1000 in a large desktop case with Zorro slots... completely braindead. Christian

On 16 July 2016 at 19:16, Christian Corti <cc at informatik.uni-stuttgart.de> wrote: Again with the "braindead" jibes. You have not clarified or explained what your objection to the machine was. It seems that there were about 5 models... A1500 -- A2000, no hard disk but dual floppies. A sensible affordable model for 1987 or so. A2000 -- an expandable A1000 with slots and provision for an on-board hard disk. A2000HD -- an A2000 with a hard disk preinstalled. A2500 -- an A2000 with a CBM processor upgrade preinstalled, either a 68020 or a 68030. If you are arguing that the A2000 should have been launched with a 68020 on the motherboard, rather than a 68000, well, yes, that would have been great -- but also very expensive, and the Amiga was a low-cost machine in a very price-sensitive market. A 68020 in 1987 might have been just too much, too expensive. -- Liam Proven ? Profile: http://lproven.livejournal.com/profile Email: lproven at cix.co.uk ? GMail/G+/Twitter/Flickr/Facebook: lproven MSN: lproven at hotmail.com ? Skype/AIM/Yahoo/LinkedIn: liamproven Cell/Mobiles: +44 7939-087884 (UK) ? +420 702 829 053 (?R)

On 17 July 2016 at 20:54, Peter Corlett <abuse at cabal.org.uk> wrote: Exactly so. This is part of the brilliance of the Archimedes, AIUI. In detailed technical ways I confess I do not fully understand, the ARM2 and its chipset's design was optimised to work with cheap DRAM with relatively slow cycle times. The OS also ran directly from ROM. Even PCs at the time copied their BIOS ROM to RAM for faster execution. Acorn designed around this. Similarly, one of the pleasant features of the Psion 3 & 5 series PDAs was that their OS ran from ROM. Thus, although the OSes were very stable & seldom needed reboots, when they did, it was reasonably quick and the machines were highly functional with, even in the late models, as little as 8-16MB of RAM, running a rich pre-emptive multitasking GUI OS. Compare with, e.g., Android or iOS, where the OS is stored in ROM but can't execute from it. Thus, slow boot times as the entire thing must be *copied* to RAM at IPL. And of course as these run not-very-cut-down 1960s/1970s minicomputer multiuser OSes, the OSes themselves occupy many hundreds of meg, these days edging to gigabyte range. -- Liam Proven ? Profile: http://lproven.livejournal.com/profile Email: lproven at cix.co.uk ? GMail/G+/Twitter/Flickr/Facebook: lproven MSN: lproven at hotmail.com ? Skype/AIM/Yahoo/LinkedIn: liamproven Cell/Mobiles: +44 7939-087884 (UK) ? +420 702 829 053 (?R)

On 19 July 2016 at 06:30, Eric Smith <spacewar at gmail.com> wrote: I will look. There's a hint here, though: https://www.epo.org/learning-events/european-inventor/finalists/2013/wilson… -- Liam Proven ? Profile: http://lproven.livejournal.com/profile Email: lproven at cix.co.uk ? GMail/G+/Twitter/Flickr/Facebook: lproven MSN: lproven at hotmail.com ? Skype/AIM/Yahoo/LinkedIn: liamproven Cell/Mobiles: +44 7939-087884 (UK) ? +420 702 829 053 (?R)

The article, as usual, talks about a whole bunch of things that are much older than the author seems to know. RISC, as a term, may come from IBM, but the concept goes back at least as far as the CDC 6000 series. Pipelining, to the CDC 7600. And if you equate RISC to load/store with simple regular instruction patterns, you can probably go all the way back to the earliest computers; certainly I can point to early 1950s Dutch computers with load/store single-address instructions. Finally, predicated instructions are also much older. It may be that the ARM team reinvented them independently, but you can find them in the Electrologica X-1, which shipped in 1958. In fact, that machine and its successor X-8 had a significantly more powerful scheme, because the flag controlling the conditional execution could be set on request, rather than being a condition code set by fixed rules. https://en.wikipedia.org/wiki/Electrologica_X1 has a brief example. paul

On 7/19/2016 9:04 AM, Peter Corlett wrote: And I go the other way, no CPU speed up was really was needed back then. Cpu's bigger than 8 bits could have decoded and executed the 1st instruction, with empty bus cycle then for video or dma or dynamic ram refresh. As for any RISC the 32 bit fetch and the ability to cache effective addresses makes its speed. Ben. PS: With the amount cache to today's cpu's, would a delay line computer be a better working model, than that of Random Access Memory?

I don't remember the earlier ARM designs, but it was my impression that DEC's StrongARM was the one that made really large strides in low power (especially power per MHz of clock speed). Interestingly enough, StrongARM was one of the few (and the first?) independent designs; it used the ARM architecture specification but not the actual logic design as others did. paul

Thanks for the backup data. I have the impression that power gating and clock gating (essentially only running small parts of the chip rather than all of it all the time) is one big reason why the SA-110 is so power-efficient. I still have an SA-110 eval board tucked away in the workshop. paul

On 21/07/2016 13:38, Liam Proven wrote: Yes and no. StrongARM was even lower power as well as faster. If you're suggesting that that's just evolution due to things like reduced process size, I possibly agree. But a StrongARM has many times as many transistors as an ARM3 (for example) let alone an ARM2, and initially ran 3 times as fast (100MHz vs 33MHz - the earliest ARM3s were 20MHz, but production runs were 25MHz and later 33MHz, and eventually SA-110 ran to over 200MHz) yet uses less power. I don't have the data sheets for ARM6 and ARM7 so I can't compare, though. As for the marketing, I recently came across an Acorn press release announcing ARM, in which Sam Wauchope (CEO) was quoted saying it delivered 100MIPS per watt, so power was indeed a selling point. I worked for Sam at the time[1], so I remember that. OK that's for one of the Acorn ARM chips, not StrongARM, but the point is still made. Not all the marketing was directed at the Acorn community. [1] and I still have my Archimedes A310 Serial No. 0000002 (and the box with all the bits and pieces :-)) as well as my A410 and R260, both from the first batches. I wish I'd kept an A500, though. All I have now is the podule to connect it to a Beeb. Anybody got the machine to put it in? -- Pete Pete Turnbull

On 21/07/2016 15:12, Liam Proven wrote: Um, isn't that pretty much what I wrote? I'm pretty sure the first batch(es) weren't rated for the full 200. Hmm. Never seen one like that. None of the ones I've seen in real life are PQFPs, and none have a heatsink. They're all plastic pin grid array packages. No heatsink at all. Nor does the datasheet for the PQFP show anything related to a heatsink. It also shows a PLCC version; no heatsink there either, and again I've never seen one. Maybe that's just because I normally only saw them in Acorn machines, of course. There's a thought. I'd be up for that, though it's not actually an A5000 I meant; the A500 was the development system - looks rather like an A310 but without the fancy front bezel, and painted blue/grey. There were only a few made. They were used internally during development - hence the podule to connect it to a Beeb, which provided the I/O early on - and in the later stages before the Archimedes launch in 1987, several were loaned to software developers. -- Pete

On 22/07/2016 00:07, "Liam Proven" <lproven at gmail.com> wrote: Pretty sure I've got 2 of those, the keyboards are made of Dark Matter. I've never dared power one up though. -- Adrian/Witchy Binary Dinosaurs creator/curator Www.binarydinosaurs.co.uk - the UK's biggest private home computer collection?

On 22/07/2016 10:04, "Pete Turnbull" <pete at dunnington.plus.com> wrote: I remember why I've never fired them up, this is the label on the one with the Beeb connecting podule: http://binarydinosaurs.co.uk/acorna500label.jpg Of course 'smoke' in these PSUs just means the mains cap has blown but I'm not sure about the fizzing. -- Adrian/Witchy Binary Dinosaurs creator/curator Www.binarydinosaurs.co.uk - the UK's biggest private home computer collection?

On 22/07/2016 20:36, Adrian Graham wrote: Well, those A500s use a standard Master 128 power supply. I can fix that :-) -- Pete

PLCC and PQFP both are plastic packages with leads on all 4 sides. But PLCC specifically means a package with J-leads: the legs come out the package side, go straight down, and tuck under the package in a J-shaped curve. PQFP (and variations with similar acronyms) have "gull wing" leads: out the side, down to near the board, and then outward resting on the board. SA110 is definitely PQFP. Here's a PLCC for comparison: http://www.batronix.com/images/products/chips/PLCC32-500-330.jpg PLCCs have fairly limited lead counts; they were common for 44 lead packages, and perhaps a bit more. PQFP goes well over 100, especially in the "fine pitch" ones with lead pitch under 1 mm. (Pain in the *** to solder...) Beyond what those can do, or for extra small packaging, we get BGA -- ball grid array. paul

On 22/07/2016 00:56, Paul Koning wrote: The StrongARM data sheet does actually show all three types: PLCC, PQFP, and PPGA. All of mine are PPGA. -- Pete

On 22 July 2016 at 10:26, Pete Turnbull <pete at dunnington.plus.com> wrote: Well, no, I meant to write exactly what I did write, drawing a comparison between the two. However, you have made me aware of the possible ambiguity in the sentence. -- Liam Proven ? Profile: http://lproven.livejournal.com/profile Email: lproven at cix.co.uk ? GMail/G+/Twitter/Flickr/Facebook: lproven MSN: lproven at hotmail.com ? Skype/AIM/Yahoo/LinkedIn: liamproven Cell/Mobiles: +44 7939-087884 (UK) ? +420 702 829 053 (?R)

Remember that the marketing in question was DEC marketing, well known for its utter ineptitude. That had its origin in Ken Olsen's belief that marketing wasn't really needed (and, for that matter, that sales people didn't need to be paid commission). I very definitely remember discussions at the time about the unprecedented power/bandwidth value delivered by the SA110. "One mW per MIPS" is one phrase that I remember from that time. paul

Until recently.

I didn't realize that. This feature makes it more like the Electrologica machines, which invented this approach back in 1958. paul

Liam Proven writes: It's not. Peter is talking about a four-bit field in the instructions. You're talking about a six-bit field in the program counter.

I realize I'm a broken record here, but PowerPC does the same thing. You have to ask for the bits to be updated (specialized forms like the "dot" instructions) unless you do an explicit compare instruction, and in many cases there is a special form to only update a certain set of bits instead of them all (e.g., "addo" updates overflow but nothing else, "addo." does overflow and CR bits, "addco." does carry too). ... bdnz, which decrements CTR and branches if not zero, ... -- ------------------------------------ personal: http://www.cameronkaiser.com/ -- Cameron Kaiser * Floodgap Systems * www.floodgap.com * ckaiser at floodgap.com -- "Use gun kata for fun! Because you worth it!" ------------------------------

On Fri, Jul 22, 2016 at 11:59:59AM -0700, Chuck Guzis wrote: [..] The condition code register can be treated as a regular register that partakes in register renaming. Effectively, you have *many* CCRs in flight, so only *reads* of the register may cause stalls. These reads are usually branches, so there's branch prediction caches to try and deal with those stalls. Unsurprisingly, the x86 ISA is brain-damaged here, in that some instructions (e.g. inc") only affect some bits in EFLAGS, which causes a partial register stall. The recommended "fix" is to avoid such instructions. Eliminating condition codes just moves the complexity from the ALU to the branch logic (which now needs its own mini-ALU for comparisons), and there's not much in it either way. Where it *does* win is that the useful instructions are all single-output and so one can use the noddy code generators found in undergraduate-level compiler construction textbooks such as the Dragon Book.

On Mon, Jul 25, 2016 at 05:54:51AM -0600, ben wrote: [...] Those backend designs are completely obsolete now. Modern machines have more grunt, so can use more complex algorithms to eke out more performance. A C++ object is a C struct, and a C++ method is a C function that has an invisible first parameter that is a pointer to the object. The generated machine code is bitwise identical. Dynamic dispatch muddies the water a bit, and is equivalent to (but not usually implemented as) a function pointer in the struct. This is not exactly rocket science. There are more features in C++, and they tend to get overused by newcomers who are blinded by the shinies, but it is possible to exercise good judgement to make it *easier* to read than the equivalent C program by tucking all the boilerplate out of the way. Is that a rhetorical question? I'm going to answer it anyway :) One of my favourite bits of CS is Andrew Tridgell's PhD thesis, from 1999. The advancement to human knowledge was his algorithm to very efficiently run a sliding window across data using rolling checksums and compute deltas in a network-efficient manner. This is the business end of rsync(1), and it can also be used for data compression. On compilation itself, there are a few interesting advances. Single Static Assignment form was invented by IBM in the 1980s; ISTR it's covered in my 1986 edition of the Dragon Book. The essence of the idea is that variables can only be assigned once, and since they are immutable values, it enables many very worthwhile optimisations that wouldn't be as simple were the values liable to change. Functional programming is finally mainstream. Yes, Lisp has been around since the 1950s, but it's been refined somewhat over the 2000s. It's used for immutability (which Lisp didn't really have) and so is easier to reason about on multi-threaded and multi-processor machines because one now doesn't need to worry about shared mutable state. There are *loads* of novel algorithms and techniques out there, but it seems to take decades for them to appear in algorithm textbooks.

The point is that instructions that set condition codes have two outputs: their output register, and the condition code register. That creates both software and hardware complexity. Software complexity in the compiler, which has to track the assignments to both these outputs and do instruction rearranging accordingly. Hardware complexity, because the instruction issue logic has to issue the instructions for the correct outcome in both these outputs. paul

No Peter is wrong. All of the modern x86 (at least the Intel CPUs) are OOO machines with large register files (192 comes to mind) that do register renaming to map the register(s) used by a particular instruction back into an ?architectural? register (no copy is actually done). The flags register is also part of the register re-naming. The only stalls occur when one instruction needs the results from an instruction that hasn?t committed it?s results yet (ie the instruction is still in ?flight?). TTFN - Guy

Power ISA also has this feature (the so-called "dot" instructions). It also has special forms of instructions for setting the overflow and carry flags, when appropriate. -- ------------------------------------ personal: http://www.cameronkaiser.com/ -- Cameron Kaiser * Floodgap Systems * www.floodgap.com * ckaiser at floodgap.com -- "Garbage in -- gospel out" -------------------------------------------------

On 21 July 2016 at 16:45, Lars Brinkhoff <lars at nocrew.org> wrote: This is a matter of historical record, AIUI. http://forum.6502.org/viewtopic.php?t=1892 There's a little more here: http://www.theregister.co.uk/2012/05/03/unsung_heroes_of_tech_arm_creators_… In essence, Wilson designed it and Furber implemented it. Wilson knew 6502 inside-out and had been designing 6502 systems while still a student, before Acorn existed, so it inspired the ARM ISA, rather than ARM actually being based on it. 6502 is widely held as being, if not actually RISC, then at least RISC-like, or as Brits put it, RISCy. http://everything2.com/title/6502 https://news.ycombinator.com/item?id=11703717 -- Liam Proven ? Profile: http://lproven.livejournal.com/profile Email: lproven at cix.co.uk ? GMail/G+/Twitter/Flickr/Facebook: lproven MSN: lproven at hotmail.com ? Skype/AIM/Yahoo/LinkedIn: liamproven Cell/Mobiles: +44 7939-087884 (UK) ? +420 702 829 053 (?R)

Lars Brinkhoff <lars at nocrew.org> writes: I've always interpreted the "inspired by" description as being about *how* the ARM was designed, rather than about the design itself. There's a story Sophie Wilson's told in several interviews about a visit to WDC... http://www.theinquirer.net/inquirer/feature/1687452/birth-world-beater | A visit Wilson and her colleague Steve Furber made to the Western | Design Centre at Phoenix, Arizona, to check out a successor to the | 6502 has passed into UK computing legend. | | The two British engineers, expecting high-tech buildings bristling | with expert brains, were astonished to find just two developers | working in a bungalow with "a bunch of college kids" on holiday | jobs. "We came away thinking if they can do it, so can we." Later in the same article: | The instruction set, Wilson said, "came from that strange place inside | my head where computer design comes from. Most engineers like to | proceed from A to B to C in a series of logical steps. I'm the rare | engineer who says the answer is obviously Z and we will get on with | that while you guys work out how to do all the intermediate steps. It | makes me a dangerous person to employ in IT but a useful one." -- Adam Sampson <ats at offog.org> <http://offog.org/>

On Sat, Jul 16, 2016 at 6:25 AM, Peter Corlett <abuse at cabal.org.uk> wrote: Clunky, yes, but it enabled government and some commercial sales back in the day because of mandatory "DOS Compatible" purchasing requirements. There were some forms that literally had a checkbox for "is this computer DOS compatible" on IT requisition forms, and if you didn't/couldn't check that box, you would likely be turned down for desktop hardware. -ethan