|
eschaton posted:the Lisp Machines used custom CPUs specifically designed for ease of Lisp implementation. (which isn't the same as "running Lisp in hardware" as some people claim.) they also had writable microcode, so the lowest-level operations could be made as fast as possible ahh, i see -- i still don't think you'd have a problem with the larger gate count spartan / cyclone devices, sounds like an interesting project though (especially to re from the existing emulators). wonder what the original were clocked at
|
# ? Dec 1, 2014 07:46 |
|
|
# ? May 15, 2024 03:53 |
|
movax posted:ahh, i see -- i still don't think you'd have a problem with the larger gate count spartan / cyclone devices, sounds like an interesting project though (especially to re from the existing emulators). wonder what the original were clocked at according to the Explorer docs at the Internet Archive, they had a 7 MHz microinstrunction clock. the processor board manual has a decent explanation of the internals including the microinstrunction format, hypothetically it should be enough to build an emulator for the cpu itself.
|
# ? Dec 1, 2014 07:57 |
|
i'd be surprised if either the nexys-3 (spartan 6) or nexys-4 (artix 7) wouldn't be enough -- hopefully you can get academic pricing microsemi's a low cost option but i think you'd need the igloo2 to fit everything
|
# ? Dec 1, 2014 08:03 |
|
movax posted:i'd be surprised if either the nexys-3 (spartan 6) or nexys-4 (artix 7) wouldn't be enough -- hopefully you can get academic pricing I ordered a Scarab miniSpartan 6+ LX a while back, hypothetically it ships soon, and I'll find out!
|
# ? Dec 1, 2014 08:06 |
|
movax posted:sw dude complaints: thanks! i'll keep this stuff in mind, esp. the need for a separate voltage watchdog and the toolchain concerns. the ISA stuff is kind of worrying too. FRAM is great for a lot of the stuff we do, and me + one of the EEs started looking at the TI FRAM msp's with an eye toward reducing bom. we've got a pair of ramtron standalone 128k fram chips on a product we just launched, and back during testing i was unable to induce failure in our emc lab even at 30 V/m in any direction. i was miffed at the time because it meant i didn't have a real test of the ecc code i had written and had to settle for mocking up various failures, but it's a testament to how hardy the stuff is what i might pitch is using the msp430 as a sort of coprocessor for datalogging and calibration data storage (a glorified replacement for a standalone fram chip and rtc) and using somebody else's cortex m4f as the main micro, although having two chips on the board that need to be programmed is either expensive or an expensive pia depending on whether we have it programmed by future/whoever or program it when it gets here
|
# ? Dec 1, 2014 15:58 |
|
movax posted:i'd be surprised if either the nexys-3 (spartan 6) or nexys-4 (artix 7) wouldn't be enough -- hopefully you can get academic pricing Idk one of their app notes crams an 8051 and some not cheap peripherals in a third of the 250
|
# ? Dec 1, 2014 16:03 |
|
FPGA and microcontroller bit janitor checking in lol, just lol if you don't janitor individual bits and clock cycles
|
# ? Dec 1, 2014 18:03 |
|
hey so here's a hobbyist's question for the actual experts itt i was gonna make a usb adapter for my ADB keyboard () because the protocol is super simple but then i found somebody else had already made one, all you had to do was stick an s-video port on a teensy and load his firmware https://geekhack.org/index.php?topic=14290.0 the problem is: it sucks so if i wanted to make my own, what's the hip good microcontroller for making usb adapters (that doesn't require me to use TI's lovely loving dev environment)
|
# ? Dec 1, 2014 18:10 |
|
eschaton posted:how many gates would an FPGA reasonably need to support to emulate a Lisp Machine CPU? I'd say one of the larger Spartan 6s would be plenty. Buy the biggest FPGA that the Webpack supports (probably either the LX45 or the LX25). The one thing that could get you is the memory - some of those LISP machines had upwards of a megabyte of RAM. Not a lot in the scheme of things, but more than a cheap FPGA will provide. So make sure you have some external memory.
|
# ? Dec 1, 2014 18:11 |
|
Blotto Skorzany posted:thanks! i'll keep this stuff in mind, esp. the need for a separate voltage watchdog and the toolchain concerns. the ISA stuff is kind of worrying too. cypress fm25vxx series? i'm using those as well, sadly no one makes fram larger than 2mbit. you could always try borrowing time on a linac to really try and induce failures, but fram is radiation-resistant, so... sw complaint/tip: - rtc peripheral on the 5989/6989 is more useful than the one on 5969 oh, i loving forgot (i can't believe this): hw complaint: - msp430 is not jtag compliant. at all. you cannot put it into a chain with other devices. if it's in a chain, it must be the first and only device. the hw responds to any jtag access with a fixed id based on revision of silicion, and you have to twiddle TEST with microsecond timing to put the part into jtag mode. or you can use spi-by-wire which again is not compliant with anything - silicon bsl is uart-based mostly unless you're lucky and can actually purchase the one with an i2c bsl so keep that in mind since you're designing an actual product that will need end-of-line testing / possible field upgrades
|
# ? Dec 1, 2014 18:40 |
|
Werthog 95 posted:so if i wanted to make my own, what's the hip good microcontroller for making usb adapters (that doesn't require me to use TI's lovely loving dev environment) pic serious answer: whichever micro someone's already used (assuming it isn't loving horrible) to do something similar since that will save you time and effort unless you don't care about that
|
# ? Dec 1, 2014 18:42 |
|
i do poo poo with bad old powerpc cpus at work and i need to write up like the entire boot process for a thing. In general, when the power is switched on how does a cpu like this know where in flash to look for the bootloader?
|
# ? Dec 1, 2014 19:07 |
|
your program counter comes up in a known state (probably) or some sort of reset generator causes it to enter a known state (such as the reset vector) from there, code happens
|
# ? Dec 1, 2014 19:10 |
|
like on msp430s or maybe its arm7s or something i forget it doesnt matter it always comes up at 0x0200 so if yo want a bootloader you stick its entry point at 0x0200 and go from there
|
# ? Dec 1, 2014 19:11 |
|
Werthog 95 posted:hey so here's a hobbyist's question for the actual experts itt there are a bunch of avr / arduino tutorials on how to do have the chip be a usb keyboard, so you could start there and figure out the adb past and how to pass everything between on your own
|
# ? Dec 1, 2014 19:14 |
|
yeah but this one is already an avr and it's poo poo
|
# ? Dec 1, 2014 19:16 |
|
i guess i could try to debug it and see exactly why it stops working when it does, and try to fix it, but other people on that forum who already know what they're doing have tried and the latest firmware still freezes up a few times a day
|
# ? Dec 1, 2014 19:17 |
|
movax posted:cypress fm25vxx series? i'm using those as well, sadly no one makes fram larger than 2mbit. fm24vxx series, the i2c part instead of the spi one. i hope cypress doesn't do something lovely with the ramtron product line (not that ramtron was an especially well-run company before the buyout). i've also tried to get some samples of mram which is another promising tech but everspin doesn't want to play ball without a much higher potential volume than i could ever guesstimate with a clean conscience also lol at the jtag stuff w/ the msp430.
|
# ? Dec 1, 2014 20:15 |
|
Werthog 95 posted:i guess i could try to debug it and see exactly why it stops working when it does, and try to fix it, but other people on that forum who already know what they're doing have tried and the latest firmware still freezes up a few times a day rig up a second avr as a watchdog and reset it when it dies?
|
# ? Dec 1, 2014 20:18 |
|
why do these nails have strange curly ridges on the sides and plus signs on the top? eh w/e *happily hammers away*
|
# ? Dec 1, 2014 20:19 |
|
maniacdevnull posted:rig up a second avr as a watchdog and reset it when it dies? for some reason the "a" key specifically kicks its rear end into gear again i have a bus pirate that i have never used, guess this might be a good chance to try it out
|
# ? Dec 1, 2014 20:24 |
|
It's a pity that putting together an ARM toolchain is much much more painful than it strictly needs to be or I'd just advise hobbyists to put one together. Get a board from Olimex that has an MCU and connector set you like Get a JTAG pod supported by OpenOCD Compile the toolchain Write a makefile Write a link script Write a crt Unfortunately it requires a fair bit of research work so it's probably more trouble than it's worth. I might write some poo poo up about my experiences in this regard some other time, but I'd argue that if you're doing this for fun and don't care about the low-level poo poo then you're kind of missing the point.
|
# ? Dec 1, 2014 20:56 |
|
hardware loving owns, except making cables, sometimes you need a cable like right loving now and have to hand assemble things and it sucks workin on a little radio project with a PIC24FJ128GA204 right now, 44-pin QFN, 16-bit, up to 96 MHz clock, 3 SPI, 2 I2C, 4 UARTs, most functions are remappable which is new compared to the PIC18s i've used before (thought that was still a high end DSP feature) its nice to have a real SPI controller instead of a glorified shift register, 128-byte fifos on tx and rx and DMA in case i need even more buffering, perfect for my application where the main function is manipulating a low speed serial stream (reclocking + inserting data at start/end) 12-bit AD instead of the standard 10-bit is also an improvement, and 40nA deep sleep consumption a consultant at work said to try kicad so trying that now, it's pretty easy to use for CAD software, not as good as Allegro at schematics but very easy to draw symbols, haven't tried the PCB layout yet but it's probably just as terrible as commercial software
|
# ? Dec 1, 2014 21:49 |
|
install diptrace
|
# ? Dec 1, 2014 21:54 |
|
i still don't know how to assemble a cable :-(
|
# ? Dec 1, 2014 21:56 |
|
Werthog 95 posted:i still don't know how to assemble a cable :-( buy a labelmaker that does shrink tubes and also buy good shrink tubes with glue, and ridiculously expensive industrial/mil connectors and the outrageously priced crimping tools, don't forget special pin insertion tools, and calibrated wire strippers, and teflon insulated wire, make a checklist and follow it, label every wire there's a reason we outsource these things i like the ecoMate m connectors from amphenol for power, IP65 or something, easy to assemble and cheap, 3+PE and 6+PE with screw/solder terminals i also like running things over standard cat5 cable, ebay has loads of bulkhead mount female RJ45 outlets with a short male cable on the end that work pretty well + are cheap
|
# ? Dec 1, 2014 22:07 |
|
Werthog 95 posted:hey so here's a hobbyist's question for the actual experts itt what sucks about it, is it something you could fix in the firmware? I have to say that this is in fact the very pro-est keyboard. at work I'm still using the first one my family bought with our Mac IIci in 1990, via the Griffin iMate adaptor. I have to plan for when the adaptor dies though, it has a button cell in it. so I'm keenly interested in whatever you come up with, pls subscribe me your newsletter.
|
# ? Dec 1, 2014 22:11 |
|
Poopernickel posted:I'd say one of the larger Spartan 6s would be plenty. Buy the biggest FPGA that the Webpack supports (probably either the LX45 or the LX25). the scarab miniSpartan 6+ I have on the way has an LX25 and 32MB SDRAM so I should be good. thanks!
|
# ? Dec 1, 2014 22:13 |
|
Werthog 95 posted:hey so here's a hobbyist's question for the actual experts itt alternate plan: open the keyboard, yank out the old guts and rig your mcu straight to the keys?
|
# ? Dec 1, 2014 23:26 |
|
sw8, i have this board booting linux off the sd card now, and i can read and write text files in the sketches, so images should be a quick next step. i also have the sketch starting telnetd and i can talk to it over link-local ethernet so i should be able to get it to dhcp too and download things to display or fart noises to make or something.
|
# ? Dec 2, 2014 00:02 |
|
movax posted:pic not joking, I once partially wrote some pic assembly code to read output from ps2 devices and it was easy as hell. writing a usb interface from scratch would be a nightmare though
|
# ? Dec 2, 2014 00:27 |
|
been working with one of analog device's fattest audio DPSs (adsp-214xx) for over a year, as many complaints as I have about the libraries and support, the chip and IDE are pretty legit at one point I rewrote a parsing routine for some encoded audio in assembly* and was proud of how many cycles it saved, until I made the same algorithmic improvements in the C code and added some compiler hints and welp the compiler beat me by a few cycles per iteration on the inner loop *because I was a freaking nose-hair away from having enough mips for worst case
|
# ? Dec 2, 2014 01:54 |
|
Werthog 95 posted:hey so here's a hobbyist's question for the actual experts itt if you don't have a usb analyzer, whatever mcu you choose, be sure there is a good working demo to use as a starting point. if you use a pic you'll already have a really good keyboard usb project to start with, you'd just have to implement the ADB protocol. i only work with pic's, maybe some other vendors also have good keyboard demos to start from.
|
# ? Dec 2, 2014 02:27 |
|
Blotto Skorzany posted:fm24vxx series, the i2c part instead of the spi one. i hope cypress doesn't do something lovely with the ramtron product line (not that ramtron was an especially well-run company before the buyout). i've also tried to get some samples of mram which is another promising tech but everspin doesn't want to play ball without a much higher potential volume than i could ever guesstimate with a clean conscience cypress guys are alright, they just revved the fm25xx parts so i assume they cleaned up the process somewhat. seem to want to support the parts for awhile yet -- what sucks is that the commercial programmer they recommend is $1k, so i had to write my own because gently caress that noise
|
# ? Dec 2, 2014 02:29 |
|
longview posted:workin on a little radio project with a PIC24FJ128GA204 right now, 44-pin QFN, 16-bit, up to 96 MHz clock, 3 SPI, 2 I2C, 4 UARTs, most functions are remappable which is new compared to the PIC18s i've used before (thought that was still a high end DSP feature) the remappable pins are sick as hell, love them on the pic24s. i think the only ones that can't really move around crazy like are i2c because you need a specific i/o cell for that another thing i love about pics is that you can program hosed up fuse (config bit) settings and assuming you didn't accidentally set a security fuse, you can fix that with no special programmer (i.e. still isp). avrs are like 'gently caress you, high-voltage time'
|
# ? Dec 2, 2014 02:31 |
|
DuckConference posted:been working with one of analog device's fattest audio DPSs (adsp-214xx) for over a year, as many complaints as I have about the libraries and support, the chip and IDE are pretty legit it's like you've never seen the 1984 documentary film 'the terminator', the machines will eventually kill us all
|
# ? Dec 2, 2014 02:32 |
|
Tin Gang posted:not joking, I once partially wrote some pic assembly code to read output from ps2 devices and it was easy as hell. writing a usb interface from scratch would be a nightmare though dsPIC/PIC24 ASM is really fun. its like a baby pdp11. you can still squeak out better performance than the C compiler, so its not completely pointless either. you probably know of him if you read the pic list, but this guy named olin from embed inc taught a class at microchips conference about ASM. he has this software package for writing in pic ask, iirc he wrote a USB stack with it
|
# ? Dec 2, 2014 02:50 |
|
Mr Dog posted:It's a pity that putting together an ARM toolchain is much much more painful than it strictly needs to be or I'd just advise hobbyists to put one together. is codesourcery still a thing? the last time i did anything serious with arm you couldn't use mainline gcc, you had to download a specific two releases old version of codesourcery, or your program would crash
|
# ? Dec 2, 2014 02:54 |
|
suffix posted:is codesourcery still a thing? how's LLVM/clang as an embedded compiler these days? should have pretty good ARM support.
|
# ? Dec 2, 2014 05:09 |
|
|
# ? May 15, 2024 03:53 |
|
i ordered a couple of spark photons cause a $19 wifi thingie development board sounds cool to me. has anyone used the spark devices? how are they
|
# ? Dec 4, 2014 05:50 |