From ljk+la at ljk.id.au Sun Apr 2 22:10:45 2023 From: ljk+la at ljk.id.au (Les Kitchen) Date: Sun, 02 Apr 2023 22:10:45 +1000 Subject: [Linux-aus] RISC-V In-Reply-To: <1809200151.2859379.1680114115542@connect.xfinity.com> References: <1932414.CQOukoFCf9@cupcakke> <20230325114528.640df75c@vorticon.teln.shikadi.net> <1809200151.2859379.1680114115542@connect.xfinity.com> Message-ID: On Thu, Mar 30, 2023, at 05:21, jon.maddog.hall--- via linux-aus wrote: ... > The architecture also allows for different extensions to the CPU. > Here is where floating point accelerators can be implemented as well as > GPUs, and other extensions that today we tend to think of as part of > the system. I will note that I programed the DEC PDP-8 "back in the > day" and it had only eight basic instructions where the system could > not even subtract (much less multiply and divide, much less do floating > point)....all it could do was add. By finding the compliment of the > number you wish to subtract, adding it to the minuend and discarding > the high order bit you could get the result. Your observation about the PDP-8's small instruction set reminded me that one of the early computers (sorry, I can't remember which one off the top of my head) had only a subtract instruction for arithmetic. You could negate by subtracting from zero, and add by working with negatives, then negating at the end: x + y = 0 - (0 - x - y) So, subtract is all you need. I did a fair bit of PDP-8 programming back in the mid-1970s ? it was about half of my Honours project in computer vision. Yes, you did subtraction on the PDP-8 by forming the twos-complement negation and then adding. But I don't think you needed to explicitly discard any bits. You got the right answer by the magic of twos-complement arithmetic (though some stuff might have ended up in the carry and overflow bits). The PDP-8 did have an assembler (and an interpreted BASIC-like language called FOCAL). But using the assembler was such trouble (all done on paper tape) that I found it more efficient to code directly in machine code. Having only eight opcodes to remember (and only 4k words of memory to fill) made that feasible. > Later on I used a PDP-11/70 time-sharing machine that had no floating > point hardware. Every time you encountered a floating point op-code > it caused a hardware exception and did the floating point arithmetic > with software, then returned from the exception. If you had a floating > point accelerator the same exception happened, but the hardware > accelerator did the work a lot faster, so the return was much faster. I did most of my Ph.D. work (also in computer vision) on a PDP-11/45. Yes, it worked like that: if you didn't have a floating-point unit you got an illegal-instruction trap on floating-point instructions, and the handler looked at the instruction that caused the trap and emulated it in software. But my recollection is different about the case when you *did* have a floating-point unit: then the floating-point operations I think were just executed as instructions ? no traps or exceptions. It was roughly similar with the early 80386 CPUs, depending on whether or not you had an 80387 floating-point coprocessor. > All of this is off the top of my head, and I am tired, so please take > this as a generality to demonstrate how a hardware extension does not > have to be part of the basic ISA. Yeah, it's the take-away generalities that matter ? about hardware extension, and about being inventive with getting the job done within the limits of currently available hardware. I also remember that one of the early computers didn't even have a program-counter register ? all for the sake of minimizing hardware. I think it was one of the PDPs, but I can't track it down. It used (core) memory location zero as the program counter, which the execution cycle could address simply by clearing the memory-address register. I leave to you to think through how this worked. ... > A nice project. My project to create the little computer down in > Brazil (caninosloucos.org) is closely following and working on RiSC-V > chips. Should that be "over in Brazil"? Same hemisphere. Yeah, a nice project. Good work! Those Labrador boards look really interesting. It looks like you have to go through the contact form to enquire about buying one. I couldn't find any listing of the prices. ? Smiles, Les. From jwoithe at just42.net Fri Apr 7 23:10:34 2023 From: jwoithe at just42.net (Jonathan Woithe) Date: Fri, 7 Apr 2023 22:40:34 +0930 Subject: [Linux-aus] Linux Australia's 2023 Grants Program is now open Message-ID: Hi all Linux Australia is pleased to announce that the 2023 Grants Program is now open. Applications are welcome from all members of Linux Australia. This year the Grant Program is divided into two categories. The grants offered by Linux Australia in previous years are now referred to as Project Grants. They provide funding for open source, open data, open government, open education, open hardware and open culture projects. The new Community Grants category offers funds to assist community groups rebuild and re-establish themselves following the interrupts of the last couple of years. We hope that the Community Grants enable groups within our community to revive past events or start something new that brings people together - in person, virtually, or both. Each category has a total grant pool of $10,000. Applications close on 30 Nov 2023 or when the grant pool has been exhausted (whichever is earlier). Full details are given on the Linux Australia Grants page[1], accessible in the Member Area after logging in to the Linux Australia website[2]. This includes grant guidelines and an outline of the application process. Members of the Linux Australia Council[3] are happy to discuss grant ideas, provide guidance in the preparation of an application, and answer any questions there may be about the program. The Linux Australia Council looks forward to receiving and evaluating grant applications from the community. Jonathan Woithe (on behalf of the Linux Australia Council) [1] https://linux.org.au/grants-program/ [2] https://linux.org.au/ [3] mailto:council at linux.org.au From kathy at kathyreid.id.au Sat Apr 8 10:12:25 2023 From: kathy at kathyreid.id.au (Kathy Reid) Date: Sat, 8 Apr 2023 10:12:25 +1000 Subject: [Linux-aus] Linux Australia's 2023 Grants Program is now open In-Reply-To: References: Message-ID: Awesomeness! And if you'd like to spread the word on the socials: Mastodon: https://fosstodon.org/@linuxaustralia/110160104880446145 Twitter: https://twitter.com/linuxaustralia/status/1644488378212323330 LinkedIn: https://www.linkedin.com/posts/linux-australia_grants-opensource-opendta-activity-7050258270082510848-a1qe Kind regards, Kathy On 7/04/2023 11:10 pm, Jonathan Woithe via linux-aus wrote: > Hi all > > Linux Australia is pleased to announce that the 2023 Grants Program is now > open. Applications are welcome from all members of Linux Australia. > > This year the Grant Program is divided into two categories. The grants > offered by Linux Australia in previous years are now referred to as Project > Grants. They provide funding for open source, open data, open government, > open education, open hardware and open culture projects. > > The new Community Grants category offers funds to assist community groups > rebuild and re-establish themselves following the interrupts of the last > couple of years. We hope that the Community Grants enable groups within our > community to revive past events or start something new that brings people > together - in person, virtually, or both. > > Each category has a total grant pool of $10,000. > > Applications close on 30 Nov 2023 or when the grant pool has been exhausted > (whichever is earlier). > > Full details are given on the Linux Australia Grants page[1], accessible in > the Member Area after logging in to the Linux Australia website[2]. This > includes grant guidelines and an outline of the application process. > > Members of the Linux Australia Council[3] are happy to discuss grant > ideas, provide guidance in the preparation of an application, and answer any > questions there may be about the program. > > The Linux Australia Council looks forward to receiving and evaluating grant > applications from the community. > > > Jonathan Woithe > (on behalf of the Linux Australia Council) > > > [1] https://linux.org.au/grants-program/ > [2] https://linux.org.au/ > [3] mailto:council at linux.org.au > _______________________________________________ > linux-aus mailing list > linux-aus at lists.linux.org.au > http://lists.linux.org.au/mailman/listinfo/linux-aus > > To unsubscribe from this list, send a blank email to > linux-aus-unsubscribe at lists.linux.org.au From craige at mcwhirter.com.au Fri Apr 14 08:25:33 2023 From: craige at mcwhirter.com.au (Craige McWhirter) Date: Fri, 14 Apr 2023 08:25:33 +1000 Subject: [Linux-aus] RISC-V In-Reply-To: <1932414.CQOukoFCf9@cupcakke> References: <1932414.CQOukoFCf9@cupcakke> Message-ID: <20230413222533.bknhmgreejukpmzw@dionach> While this thread is fresh on my mind, Pine64 people have dropped these RISC-V tablets: https://pine64.com/product-category/pinetab/ Suitable for hackers, not consumers. On Sat, Mar 25, 2023 at 11:21:33 +1100, Russell Coker via linux-aus wrote: > https://www.earth.li/~noodles/blog/2023/02/visionfive-2-impressions.html > > Some of this recent RISC-V hardware seems pretty good. A 10 hour Debian > kernel build suggests that it's about 2% the CPU speed of a high-end server > CPU from 2015 which is pretty decent for an embedded device, I still have some > laptops in use with similar performance. > > I think it would be good if we had a group of Linux people who have the time > and interest to do stuff with this (NB this does not mean me) and a Linux > Australia grant to buy a set of identical RISC-V systems for them. > > -- > My Main Blog http://etbe.coker.com.au/ > My Documents Blog http://doc.coker.com.au/ -- Craige McWhirter Signal: +61 4685 91819 Matrix: @craige:mcwhirter.io Mastodon: @craige at mcwhirter.io -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 833 bytes Desc: not available URL: From russell at coker.com.au Mon Apr 17 12:49:45 2023 From: russell at coker.com.au (Russell Coker) Date: Mon, 17 Apr 2023 12:49:45 +1000 Subject: [Linux-aus] Free servers Canberra -> Melb Message-ID: <3369125.KgjxqYA5nG@cupcakke> If you are located in Canberra, Melbourne, or somewhere conveniently between them on Saturday and need a free server for FOSS or other non-profit community work then please contact me by private mail. These won't be new or great servers, DDR3 RAM and CPUs with a speed to match, but 2 CPUs with the speed of DDR3 server hardware is still decently fast by today's standards. Also if someone needs 1TB SAS disks then I could supply some disks as probably most people who want the servers will put in SATA SSDs to make them quiet enough for home use. Also there's a Dell 2950 system that would be DDR2. Not suitable for use as a server nowadays but could be good for a student who wants to learn about enterprise hardware with zero cost if they stuff up. I'm getting some gear in Canberra this week and driving to Melbourne on Saturday. I can give stuff away in Canberra over the next few days and in Melbourne in the next few weeks. Please include in your email a brief summary of how the hardware will help you do something good for society. -- My Main Blog http://etbe.coker.com.au/ My Documents Blog http://doc.coker.com.au/ From russell at coker.com.au Sat Apr 29 18:39:55 2023 From: russell at coker.com.au (Russell Coker) Date: Sat, 29 Apr 2023 18:39:55 +1000 Subject: [Linux-aus] Flounder meeting 6th May Message-ID: <5669628.1IzOArtZ34@xev> https://flounder.linux.org.au/events/flounder-may-2023-linux-nokia-n900-anti-spam/ The next Flounder meeting will be on the 6th of May at 1PM Melbourne time (03:00 UTC). It will have a lecture by Yifei about running Linux on the Nokia N900 phone followed by a hands-on tutorial on setting up anti-spam measures on the Postfix mail server. There will also be the usual summary of Linux news and general discussion of FOSS related things. Meeting will be at http://b.coker.com.au. No need to register just click on the link on the day. -- My Main Blog http://etbe.coker.com.au/ My Documents Blog http://doc.coker.com.au/