Taniwha

38 ms·

421.
by Taniwha 3y ago
I'm pretty sure the first generation MIPS/ARM/etc had off chip (but very close) caches
422.
by Taniwha 3y ago
I think the big thing the RISC vs CISC wars articles always seem to miss or play down is the effect that large caches near or on-chip had in the way that people made trade offs in CPU design. CISC (heavily encoded) instruction sets made se
423.
by Taniwha 3y ago
Yup it was really lo-res - it was the 70s the cold war was in full force - those screens were being put together by what at the time was called a 'super computer' probably not as powerful as your phone
424.
by Taniwha 3y ago
These tests were done last week: https://www.newshub.co.nz/home/new-zealand/2023/04/architect...
425.
by Taniwha 3y ago
I was a radio ham in the early 70s used to hang out with some guys who were snarfing weather satellite data - essentially it worked this way - the satellites passed over and either spun along their axis or had a spinning sensor - that made
426.
by Taniwha 4y ago
Oh this is just going to push all the anti-vaxxer conspiracy theorists' buttons
427.
by Taniwha 4y ago
One of the New Zealand cell phone companies has done this same deal and are advertising it heavily at the moment (along with SpaceX branding, which may not be the positive they think it is right now)
428.
by Taniwha 4y ago
Interestingly there were, I think, 3 companies working on similar projects at the time (including TM) - the others didn't make it to market (mostly due to the dot-com bust and the sudden drop in available funding). A lot of the IP that
429.
by Taniwha 4y ago
The old Burroughs systems (up to at least the B7700) didn't really have MMUs in the traditional sense - their descriptors only reserved 20 bits for (word addresses) so they were limited to ~6Mb of addressing - not a big deal when we ha
430.
by Taniwha 4y ago
well sort of, similar stuff ... though it's worth remembering that Burroughs security depends on only specially blessed programs called 'compilers' being able to make code - because the underlying architecture has no real pro
431.
by Taniwha 4y ago
Here in NZ we import a lot of 2nd hand Japanese vehicles (helps that we drive on the same side of the road), in the city I live the most popular EV is a 2nd hand Japanese Leaf - we have one for an around town day to day car (complemented by
432.
by Taniwha 4y ago
Actually I've previously made the same claim about the x86 .... I'd argue that of all its generation of CISCS (vax/68k/32K/etc) it was the most RISCy (apart from the microcoded segment crud) almost all it's ins
433.
by Taniwha 4y ago
and yet it was a 32-bit core, vax class architecture, so unix was a relatively easy port. I think the really big problem with the 432 was all that hard wired microcode - rumor has it that it was buggy enough that subroutine calls could take
434.
by Taniwha 4y ago
But binning is largely binning against performance curves: "we doped this side of the wafer just a little too much and it's a little slow, but this one from the other side is just right" - while checking for faults (full chip
435.
by Taniwha 4y ago
Remember that at the time no one put a main-frame class chip on a single die - the 68ks/32ks, and much later 386s were the first generation who managed to pull off putting a large architecture on a chip (I'm trying to make a disti
436.
by Taniwha 4y ago
I'm turning 65 in a couple of months, been making a living doing this stuff for money since I was in college - started programming 53 years ago (using cards) - in '84 I moved to the US I think most of the people I worked with then
437.
by Taniwha 4y ago
In NZ we generally don't have ANY deductions (nor a tax on capital gains) - this makes filing tax easy - if you have one employer chances are they got your tax exactly right - most people don't even need to file - and certainly no
438.
by Taniwha 4y ago
Here in NZ it's as easy, except you can put your donations in ahead of time (as you make them) and get the donation tax refund right then, not wait for the end of the year
439.
by Taniwha 4y ago
Actually I think it's because they don't want to spend the money to create sanitised international departure spaces. It's a mistake that means that one can't transit through the US without passing through US immigration
440.
by Taniwha 4y ago
One of the big problems with the US is that unlike any other country they don't have exit procedures, there's nowhere you go and get your passport stamped, if the airline or the immigration officials screw up you have no proof you
441.
by Taniwha 4y ago
(I design memory controllers ....) you can sort of do that depending on where your byte boundaries are (and whether your architecture needs to be able to do single byte writes to memory) - more though I was trying to point out that historic
442.
by Taniwha 4y ago
I have built CPUs with 9-bit bytes (because of subtle MPEG details), they made sense at the time and ram with 9-bit bytes was available at a reasonably low premium - that probably wasn't true when the 432 was a thing, RAM was so much m
443.
by Taniwha 4y ago
It depends - at the time capability machines were all the rage - the idea there is that you add EXTRA bits to memory (say 33-bit or 34-bit memory - Burroughs large systems were 48-bit machines with 3-bit tags - plus parity) with careful rul
444.
by Taniwha 4y ago
It's actually not all that different from the Burroughs large systems architectures (B5000/B6700/A-series) which were initially released in the late 60s ... stack machines, similar descriptor based memory structures, tagged m
445.
by Taniwha 4y ago
I don't know the original reason for choosing the shift register, might have been that it involved lots of short wires between flops so the timing is easier to get right - but essentially they will switching to the big mux/etc nex
446.
by Taniwha 4y ago
So there's a rotating flame front going in one particular direction .... anyone know does it impart angular momentum to the thing it's propelling?
447.
by Taniwha 4y ago
Probably a bit smaller - and doesn't have a multiplier/divider (it does have the minimal MQ register instructions), and it has a minimal IO interface In some sense it's a toy because the TT internal clock is so slow and it ne
448.
by Taniwha 4y ago
I'll also note that all Tiny Tapeout projects are hosted on github and you can browse through them if you want to see how they're done
449.
by Taniwha 4y ago
I submitted 2 CPUs to TT2 and a PDP8 (12 bits) to the current TT3. The major limitations are the relatively small number of gates, and the external interface (8 inputs including clock/reset, and 8 outputs) - and the external multiplexo
450.
by Taniwha 4y ago
yeah lost a day this week to bloody snaps

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