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Comment Re:Terrible interoperability (Score 2) 355

Amen to the "Ball of hurt".

I design USB3 H/W....what. a. piece. of. shit. I have truly given up hope of engineering anything that will ever work universally, even Intels interfaces which you would like to believe would be a model reference design look like crap when you plug them into a gizillion dollar Agilent USB3 analyzer. Should I be be surprised? Probably not, USB has never exactly been the premium interface has it? Firewire didn't go away because USB was technically superior thats for sure. Thunderbolt just friggin' works, day in, day out, incredible and reliable performance. Sure cables are expensive, they have all sorts of clever active electronics...because...thats what it takes to make 10G in a consumer application work...not a $1.99 piece of injection molded crap from god knows what Asian hell chemical works. In fact Thunderbolts worst problem is ....Intel.....who seem to have a bizarre attitude towards people who want to buy components from them to make peripherals...I honestly don't get it.

I can relate. The USB 3.0 spec is a committee beast. It is difficult to read it and understand very clearly how you are supposed to put it into practice, and that's a problem for someone like me who is writing an implementation from the ground up.

Probably the biggest gripe is the compliance tests. The idea is that every manufacturer goes to the USB Implementers Forum and runs standardized tests on their widget so they can say "hey, it passed the tests, it's ready for the market.". But in real life, the tests are woefully lacking. I suspect they were designed that way on purpose.

One of the big players selling verification equipment (Lecroy) actually went out and cooked up their OWN compliance tests that you run in addition to the USBIF's -- and they're far more useful. I was passing the USBIF tests mostly but failing the Lecroy tests.

I have not seen 1 shipping device that actually passes all the tests. Intel, NEC, Renesas, VLI, whatever host or device chip you pick, they all fail some of the tests. And they don't always play nice together. The protocol is structured in a such a way that it's very, very, hard to conclusively test an implementation and say "yup, it works". Instead you have to go probing and test for tons of odd and random occurences, and if they don't happen, then it must be working.

To get my core working I've already been investigating fudges.. yes, all shipping devices have them. You wouldn't believe all the kludges that've accumulated in something like the Windows USB stack. Luckily I dont have to worry about that, working on the hardware :)

Comment Never failed me (Score 1) 88

I recognize this place, made some boards there :) US based PCB fab is more expensive, but quicker and QUALITY. Chinese houses like pcbcart? 6/15 of my boards made with them failed. I even stayed away from their spec limits quite a bit. Half of those that failed did so within a few heat/cool cycles of running (they have FPGA and SDRAM on them, so not THAT much heat). The rest developed electrical shorts that were still there even after I'd completely depopulated the boards. Advanced Circuits? Never have they failed. Even the PCBs I abused with a rework station never lifted any traces. Even the 0.5mm SMD pads that lifted like paper off the PCBcart boards, they are STILL THERE on the 4pcb/advanced circuits prototype. I just reworked my design into 4 layers and did another proto from them. No problems either. If you are a student, you can get on board their 33each (2 layer) and 66each (4layer). Note their shipping charges are a tad high so it works out to about $48 and $88, respectively. Oh yeah, I wasn't paid by them either, I just am a happy customer. Started using them in high school (thanks Forrest) and now near the end of college they have never let me down.

Comment Innovation (Score 4, Interesting) 131

This article seems to miss the point that the N64 introduced a number of new things that Sony shamelessly copied - take the Rumble Pak and analog stick for example.

The games are different from the PSX - Mostly "meh" titles, and maybe a dozen games that were to die for.

I'm currently developing homebrew for the N64, and from a hardware standpoint, the design is very forward-looking. The RCP 3d coproccessor was fully upgradable - the game transferred microcode to the RCP to tell it how to draw polygons, for example. This was a very sensible design choice - as Nintendo optimized their Fast3D microcode, you got better speed in the game you were developing.
Unfortunately, Nintendo neutralized that advantage by not making microcode tools available until it was too late - some developers did some amazing things by writing their own microcode (Boss Games, and Rare for example)
It was a pretty solid design, the only glaring limitation I can think of is the small (4KB) texture cache and high memory latency (making the N64 fill rate limited, instead of polygon limited.)

It's a shame Nintendo didn't make it easier to develop for - it seems they kinda pulled a Sega with it, and lost some 3rd party support. In any case, it's quite an adventure to learn about.

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