a thread about janitoring individual bits and using oscilloscopes and stuff

The Something Awful Forums > Discussion > Serious Hardware/Software Crap > YOSPOS > a thread about janitoring individual bits and using oscilloscopes and stuff

Blotto Skorzany: Nov 7, 2008; He's a PSoC, loose and runnin'
came the whisper from each lip
And he's here to do some business with
the bad ADC on his chip
bad ADC on his chiiiiip

movax posted:

personally i would de-feature msp430s out of existence, i hate the loving things (mostly the fram family) and documentation

can you give me a litany of complaints about them, the fr57xx is one of the chips in consideration for a design i'll be working on in a couple of months

# ¿ Dec 1, 2014 05:09

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# ¿ Apr 29, 2024 15:59

Blotto Skorzany: Nov 7, 2008; He's a PSoC, loose and runnin'
came the whisper from each lip
And he's here to do some business with
the bad ADC on his chip
bad ADC on his chiiiiip

movax posted:

sw dude complaints:
- lovely toolchain (ccs, mspgcc, gcc-msp430), iar wasn't considered because it's windows only
- lovely docs
- weird-rear end isa (certain operations very expensive like bit shifts ) also forget about doing intensive math

hw (my) complaints:
- lovely docs
- weird pinouts sometimes
- fr5969 has funky errata relating to leakage currents on certain pins
- weird rear end fram memory controller timings that changed from stepping to stepping
- took them six steppings to get release silicon out which is mildly terrifying
- you will need a reset supervisor or otherwise clean reset source, code will corrupt in brownout conditions (the SVS module on the frxxxx parts for some reason is slightly different than other msps)

the fr57xx series is older and their first go at the whole fram thing; new designs i'd check out the fr5989, if you can get it (i bought the first batches out of the factory)

like i said though, i'll give them props for the absurdly low power consumption and fram reliability

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

Blotto Skorzany: Nov 7, 2008; He's a PSoC, loose and runnin'
came the whisper from each lip
And he's here to do some business with
the bad ADC on his chip
bad ADC on his chiiiiip

movax posted:

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

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

Blotto Skorzany: Nov 7, 2008; He's a PSoC, loose and runnin'
came the whisper from each lip
And he's here to do some business with
the bad ADC on his chip
bad ADC on his chiiiiip

what do y'all use for lab notebooks? i've been using national computation books but they don't lay flat and tend to fray/dogear more than i like

# ¿ Dec 4, 2014 20:21

Blotto Skorzany: Nov 7, 2008; He's a PSoC, loose and runnin'
came the whisper from each lip
And he's here to do some business with
the bad ADC on his chip
bad ADC on his chiiiiip

Mr Dog posted:

no wait i'm the flash protection page at 0x400 that can brick your mcu if you write code over it. because why the gently caress not

months later, still lolin @ dis

# ¿ Dec 5, 2014 16:13

Blotto Skorzany: Nov 7, 2008; He's a PSoC, loose and runnin'
came the whisper from each lip
And he's here to do some business with
the bad ADC on his chip
bad ADC on his chiiiiip

now, program it... to love

# ¿ Dec 7, 2014 04:06

Blotto Skorzany: Nov 7, 2008; He's a PSoC, loose and runnin'
came the whisper from each lip
And he's here to do some business with
the bad ADC on his chip
bad ADC on his chiiiiip

Bloody posted:

c bits s: dealing with special snowflake ADCs is annoying. 20-bit output range? yeah that won't be annoying at all

one of the new super-SARs, or have you been saddled with the builtin adc on a psoc?

# ¿ Dec 8, 2014 22:42

Blotto Skorzany: Nov 7, 2008; He's a PSoC, loose and runnin'
came the whisper from each lip
And he's here to do some business with
the bad ADC on his chip
bad ADC on his chiiiiip

i had wondered for a while why the stack overflow checks in freertos never seemed to work (always reported that no overflow had occurred) and the mpu exception handler that i wrote always got called instead. i was poking around in the scheduler for other reasons and found this

code:

		//taskFIRST_CHECK_FOR_STACK_OVERFLOW();
		//taskSECOND_CHECK_FOR_STACK_OVERFLOW();

i guess that's why setting configCHECK_FOR_STACK_OVERFLOW to the appropriate value didn't do anything. i'll have to check git to see whether a coworker did this or if the main distribution had this bug at the time we grabbed it.

# ¿ Dec 11, 2014 17:10

Blotto Skorzany: Nov 7, 2008; He's a PSoC, loose and runnin'
came the whisper from each lip
And he's here to do some business with
the bad ADC on his chip
bad ADC on his chiiiiip

freertos was ok for the product i used it in. it certainly has some flaws but at the end of the day it does what it says on the tin: it gives you a task scheduler, queues and some concurrency primitives and has a reasonable memory footprint. the source is kind of gross but it won't keep you from getting your work done. if you've got some logical concurrency in your application go for it, if you don't need that don't bother and just stick with a superloop or state machine or interrupts or whatever you were doing imo

# ¿ Dec 12, 2014 19:27

Blotto Skorzany: Nov 7, 2008; He's a PSoC, loose and runnin'
came the whisper from each lip
And he's here to do some business with
the bad ADC on his chip
bad ADC on his chiiiiip

the danger isn't the fuse itself blowing up, but rather the lovely non-hrc glass fuse not being able to terminate a very high current condition leading to other stuff blowing up

# ¿ Dec 19, 2014 20:52

Blotto Skorzany: Nov 7, 2008; He's a PSoC, loose and runnin'
came the whisper from each lip
And he's here to do some business with
the bad ADC on his chip
bad ADC on his chiiiiip

well no, SPI will happily run up to 40 mhz and lol at looking at a 40 mhz square wave with a scope that samples at 25 ms/s (or even a 6 mhz square wave really, you're going to cut off harmonics and a perfectly clean clock is going to look like garbage)

# ¿ Dec 19, 2014 22:28

Blotto Skorzany: Nov 7, 2008; He's a PSoC, loose and runnin'
came the whisper from each lip
And he's here to do some business with
the bad ADC on his chip
bad ADC on his chiiiiip

Jonny 290 posted:

basically as close as you can get to manipulating the supernatural

incorrect. yosvape is as close as you can get to manipulating the supernatural

# ¿ Dec 19, 2014 22:48

Blotto Skorzany: Nov 7, 2008; He's a PSoC, loose and runnin'
came the whisper from each lip
And he's here to do some business with
the bad ADC on his chip
bad ADC on his chiiiiip

Base Emitter posted:

dear robot nerds, can yall recommend a site for buying tiny mechanical parts e.g. gears, shaft couplers, shafts, & the like? i have some tiny little stepper motors and want to step tiny little things

mcmaster

# ¿ Dec 23, 2014 16:09

Blotto Skorzany: Nov 7, 2008; He's a PSoC, loose and runnin'
came the whisper from each lip
And he's here to do some business with
the bad ADC on his chip
bad ADC on his chiiiiip

i've got an early 2000s tek at work and it can only export to <=64mb usb sticks lol

# ¿ Jan 7, 2015 19:39

Blotto Skorzany: Nov 7, 2008; He's a PSoC, loose and runnin'
came the whisper from each lip
And he's here to do some business with
the bad ADC on his chip
bad ADC on his chiiiiip

they use mspgcc now don't they

# ¿ Feb 3, 2015 15:17

Blotto Skorzany: Nov 7, 2008; He's a PSoC, loose and runnin'
came the whisper from each lip
And he's here to do some business with
the bad ADC on his chip
bad ADC on his chiiiiip

'look at the asm' is always the right answer. in cases where it doesn't seem to be the right answer, you're asking the wrong question.

# ¿ Feb 3, 2015 16:04

Blotto Skorzany: Nov 7, 2008; He's a PSoC, loose and runnin'
came the whisper from each lip
And he's here to do some business with
the bad ADC on his chip
bad ADC on his chiiiiip

Mr Dog posted:

I'm doing firmware for a lil battery powered wireless sensor

it has a 1.5F supercapacitor on it for some reason

makes power cycling more of a pain than it needs to be

put a relay in series with the supercap imo

# ¿ Feb 10, 2015 19:22

Blotto Skorzany: Nov 7, 2008; He's a PSoC, loose and runnin'
came the whisper from each lip
And he's here to do some business with
the bad ADC on his chip
bad ADC on his chiiiiip

Mr Dog posted:

and anyway, instead of smoothing out the current spike it probably causes a Tohoku-scale inrush when you first plug the batteries in so it doesn't really seem like a win to me. like i'm pretty sure this thing would arc if alkaline battery chemistry were capable of it

lol definitely. i'd almost be worried about popping alkalines if you power cycle it too frequently, they don't like big ol' current spikes that much especially when they've been run down a ways

# ¿ Feb 10, 2015 20:01

Blotto Skorzany: Nov 7, 2008; He's a PSoC, loose and runnin'
came the whisper from each lip
And he's here to do some business with
the bad ADC on his chip
bad ADC on his chiiiiip

maybe a xeltek is01? i think our mfg folks use that

# ¿ Feb 15, 2015 15:53

Blotto Skorzany: Nov 7, 2008; He's a PSoC, loose and runnin'
came the whisper from each lip
And he's here to do some business with
the bad ADC on his chip
bad ADC on his chiiiiip

hopefully it isn't doing something moronic with the flash like trying to write it byte-at-a-time resulting in 256 read-modify-writes per page

# ¿ Feb 16, 2015 04:09

Blotto Skorzany: Nov 7, 2008; He's a PSoC, loose and runnin'
came the whisper from each lip
And he's here to do some business with
the bad ADC on his chip
bad ADC on his chiiiiip

the necronomicon

# ¿ Feb 16, 2015 19:06

Blotto Skorzany: Nov 7, 2008; He's a PSoC, loose and runnin'
came the whisper from each lip
And he's here to do some business with
the bad ADC on his chip
bad ADC on his chiiiiip

i'm improving a blue screen of death that i wrote for a product firmware a while back to add some debug info so that i have something to go on if a unit crashes in the field. the arm cortex m3's nvic helpfully pushes some registers (eight of them) onto the stack before it starts executing an interrupt handler (eg. the mpu exception handler, where my code to draw the bsod lives). is there a less lovely way to grab stuff off the stack than

register void *sp asm("sp");
struct register_dump *registers = sp;

# ¿ Feb 18, 2015 22:46

Blotto Skorzany: Nov 7, 2008; He's a PSoC, loose and runnin'
came the whisper from each lip
And he's here to do some business with
the bad ADC on his chip
bad ADC on his chiiiiip

those intrinsics are perfect, tanks mang

# ¿ Feb 19, 2015 02:30

Blotto Skorzany: Nov 7, 2008; He's a PSoC, loose and runnin'
came the whisper from each lip
And he's here to do some business with
the bad ADC on his chip
bad ADC on his chiiiiip

Bloody posted:

i certainly owned future-self several times today, as i spent today writing many lines of verilog and tested zero of them, including a few serializers and deserializers

Nice!

# ¿ Feb 20, 2015 00:37

Blotto Skorzany: Nov 7, 2008; He's a PSoC, loose and runnin'
came the whisper from each lip
And he's here to do some business with
the bad ADC on his chip
bad ADC on his chiiiiip

i found three bugs in the bugtracker today that i meant to fix for the next release but forgot about but i'm not doing poo poo about them until after the release because the last release candidate is 90% of the way through validation testing :toot:

also i got the improved bsod working and whatnot, i was confused for a bit because my test values that i was stuffing in registers were getting mangled but then i realized that i used mvn instead of mov lol

# ¿ Feb 20, 2015 00:40

Blotto Skorzany: Nov 7, 2008; He's a PSoC, loose and runnin'
came the whisper from each lip
And he's here to do some business with
the bad ADC on his chip
bad ADC on his chiiiiip

and also get the yellow working so you don't have the semipredicate problem ("is this showing zero or did the board burn out?")

# ¿ Mar 7, 2015 21:03

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# ¿ Apr 29, 2024 15:59

Blotto Skorzany: Nov 7, 2008; He's a PSoC, loose and runnin'
came the whisper from each lip
And he's here to do some business with
the bad ADC on his chip
bad ADC on his chiiiiip

DNova posted:

yes you're right sorry I didn't mean to promote a hostile environment to raspberry pis

raped idiot

# ¿ Mar 13, 2015 20:27

The Something Awful Forums > Discussion > Serious Hardware/Software Crap > YOSPOS > a thread about janitoring individual bits and using oscilloscopes and stuff