eschaton posted:

how many gates would an FPGA reasonably need to support to emulate a Lisp Machine CPU?

like first-gen, the CADR/Lambda/TI Explorer

Bloody posted:

serious q are there any non horrible ways of input fuzzing with verilog testbenches

Bloody posted:

its true. instead of using some of the new for loop constructs sysV allows, i'm writing a c# program to autogen some spaghetti code.

Bloody posted:

i don't know what these things mean

eschaton posted:

if i were to install the Xilinx tools on Linux, would that be sufficient for new development if I just did everything through makefiles? or does the tooling really insist on an IDE-generated project file and so on, even for command-line builds?

_{kind of like the IDE that I work on does}

Bloody posted:

im back to this problem (lol)

i have an fpga dev board with an ulpi chip on it but i have no ulpi ip and i cant find any and im reading the spec and it sounds tedious as gently caress why isnt this easier

said dev board also has pci-e 1x and i think ip for it but at some point i want to hook this to a laptop and said laptop probably doesnt have expressport and i know i dont have an adapter and we could buy all these things but i suspect usb would just be preferable

it also has some gigE phy but it doesnt seem to have a data sheet and i think sgmii is just a different flavor of nightmare from ulpi so w/e

movax posted:

vivado / xilinx still doesn't understand the concept of people wanting to version control stuff though.

why the gently caress do i have to hand-write my own tcl scripts to run the entire build flow because you fucks are unwilling to jump into the 21st century and embrace source control

movax posted:

don't even get me started on trying to version control the shitshow that's version controlling the export process over to their sdk tool as well (an eclipse-based system)

at least eclipse has some user community that's figured out ways to deal with that special brand of bullshit

movax posted:

mostly i've got some simple parameterized modules where i want to barf if the idiot user tries to make width 0 registers or similar things

ovm sounds like something that'd be cool to start using though -- our stuff is so simple right now / so tiny (igloo nano fpgas) that it's not required, but i want to learn more about it

JawnV6 posted:

the synthesizer looks at those directives? thought they were simulation-only

I've had hdl compilations that took 24+ hours, so the difference in compile time and cycle 1 can be huge

Barnyard Protein posted:

yeah dsp is awesome. what area of dsp are you interested in? i'm trying to learn it on my own, focusing on fast algorithm implementation. i wish i were in a position to go back to grad school full time, i'd do dsp.

e: this is the book i'm working through right now http://www.amazon.com/Fast-Algorithms-Digital-Signal-Processing/dp/0201101556. its focusing on fast convolution algorithms, and its awesome. however its 31 years old and i have no clue if the info is even relevant any more. it'd be nice to have a set of experts at my disposal that are obligated to entertain my questions and ideas

Sagebrush posted:

pics are garbage for grognards stuck in 1995

Microchip's Actual Website posted:

movax posted:

hahahahahaha

was this picked because someone prototyped with some kind of ~~maker~~ product?

also lol at saving 30 cents for something that isn't gonna (I assume) break 10K units -- how many hours is $3K saved?

Sagebrush posted:

spam spam spam


i did this and it's fuckin' great



100nF capacitor reads as 72-84nF when repeatedly tested. badass

i know it's p basic stuff from an electronics standpoint but having the scope has been like...such a huge change in what I can do. like my old analog scope still does what it does, but it's a lot bigger pain for stuff like this -- I'd have to build an oscillator and make measurements on the graticule and blah blah blah. i've been screwing around with electronics since i was 7 years old at science camp, and over the years there have been these moments when it was like a huge step forwards in capability, another level opening up -- when i got my first decent multimeter (age 12), when i got a good soldering station (age 16), when i built my first arduino from a kit (age 20), and this is another one. i'm super stoked by all that this tool has suddenly enabled.

Sagebrush posted:

i assume that's cause of leakage or tunneling or something as it gets closer to the breakdown voltage of the dielectric?

hobbesmaster posted:

can you even toggle the pullup that fast?

Sagebrush posted:

what were they even going for here?

if it's something like a 5mm LED you can do it literally as GPIO -> resistor -> LED -> ground

why is there one transistor driving the LED and another transistor to drive that transistor (also is this a darlington pair?)? i guess i could see that being a thing if the LED is too powerful for the GPIO directly, and you picked some terrible drive transistor that needs more current to saturate than the microcontroller can provide?

mosfets or bust

longview posted:

that's pretty terrible, but you gotta admire that dedication to saving $0.001 by not putting in an extra resistor to make it work

it's not like a SN74LVC2T45 is that expensive

hobbesmaster posted:

i was about to ask how but then I realized the registers are probably separated by a letter or something

Sapozhnik posted:

why does anybody use atmel for anything

it was an iffy choice even before microchip bought them out and jacked up all the prices 500%

like it's not a bad 8-bit architecture by any means, it's just that we live in the year 2017 and cost-competitive 32-bit microcontrollers which can be targeted by the same compilers that see massive use for desktop and server applications are things that exist

Sagebrush posted:

they do the job for a lot of dumb little things and unlike PIC their toolchain isn't garbage

ratbert90 posted:

I was thinking about using a sha256 authentication chip from them. Seems cheap and would be nice for storing a private key yes?

Is there another company/chip I should look at?

Edit:
Something like this: http://www.microchip.com/wwwproducts/en/ATSHA204A#buy

50c~ per unit seems ok.

Sagebrush posted:

well, it's running on a cortex-m4 and i'm operating only on uint32_ts. using the mask to ensure safety for signed types makes sense. is it one cycle slower to do that, though?

good to know that for this case it should work either way, though. that's what it seemed like but wanted to be sure.

on a related note, is this the right practice?

code:

void main() {
  uint32_t boobs;
  byte poop = byte foo(boobs>>24);
}

byte foo (byte bar) {
  return bar;
}

the function wants a byte, but i'm giving it a uint32 and shifting to recover the MSB. what is happening behind the scenes? is there a hidden internal conversion from uint32_t to byte? does it just select the last 8 bits of boobs after the shift? it *seems* to do what it's supposed to, but having not read the C reference, i'm unsure.

similarly, if i passed a pointer to boobs, would that also recover the MSB because it just reads the first 8 bits from that location?

Malcolm XML posted:

What's the best PCB design software for idiot hell fuckers like me

hobbesmaster posted:

just use keil and cmsis

qirex posted:

I saw this on an audiophile website and decided more people needed to see it
this interview was conducted to promote an $80,000 cable