Paul & Sabrina's cheap DIY 144v motor controller

[brihoo2k]

Originally Posted by MazdaMatt

brihoo... ratshack has HUGELY overpriced breadboards. The best thing to do, IMO, is go to an electronics supplier for them. About 1/3 the price of radioshack and quality controlled (unlike ebay).

Yes I agree that most things are overpriced at the shack and it seems these days that if its not about cell phones then they're not much help. It was just a suggestion out of convience.

[dcb]

I know we keep jacking this thread, but I don't mind ratshack component prices. I'm just glad I can run out and get stuff still, for when I fail to plan ahead.

[MazdaMatt]

as an electronics geek it is frustrating to go into their "parts" section and see a choice of 5 individually packed resistors for a dollar each...You used to be able to get a huge slection of transistors, caps, resistors, 7400ICs, timer ics, blah blah blah I do understand their cutting back, though. There is bigger money in iPod chargers and bluetooth earsets than there is in transistors... people can't open up today's electronic products and fix them like they used to.

[nubie]

Originally Posted by MazdaMatt

people can't open up today's electronic products and fix them like they used to.

can't or don't? Or maybe I'm not human?

@Paul, don't let surface-mount stop you, there are many many benefits to surface mount.

If you are just worried about soldering to the surface-mount chip then get a Schmart board ( SchmartBoard - The world's best circuit prototyping system ) or a dip adapter and have somebody else do the SMD soldering.

SMD soldering isn't all that hard, you just need a steady hand, keen eye, and a nice sharp ~15watt iron. Here is my PCI-e x1 video card with a repair because I was over-zealous with the dremel.

[MazdaMatt]

nice fix add some hot glue for longevity! Why on earth did you attack it with a power tool?

A dozen pages back i gave paul some instructions on SM soldering. Certainly nothing to be scared of except for BGA packages and 100+pin packages. Leaded solder helps... a LOT.

"most" people can't fix "most" of today's electronics. and by most, i mean 99.99% of people.

[NiHaoMike]

Originally Posted by nubie

can't or don't? Or maybe I'm not human?

@Paul, don't let surface-mount stop you, there are many many benefits to surface mount.

If you are just worried about soldering to the surface-mount chip then get a Schmart board ( SchmartBoard - The world's best circuit prototyping system ) or a dip adapter and have somebody else do the SMD soldering.

SMD soldering isn't all that hard, you just need a steady hand, keen eye, and a nice sharp ~15watt iron. Here is my PCI-e x1 video card with a repair because I was over-zealous with the dremel.

I would have used a scalpel to remove the insulation over the damaged trace and then soldered a strand of wire across it. Keeping the signal lines as close to the same length as possible is very important in high frequency circuits.

[nubie]

Originally Posted by MazdaMatt

"most" people can't fix "most" of today's electronics. and by most, i mean 99.99% of people.

Yeah, I just got commended for that soldering by "Shamino" Tan on the VR-Zone forums, he holds several world records for overclocking shamino tan - Google Search .

Originally Posted by NiHaoMike

I would have used a scalpel to remove the insulation over the damaged trace and then soldered a strand of wire across it. Keeping the signal lines as close to the same length as possible is very important in high frequency circuits.

Yes I did realize that, but it has been in use for over a year now (notice that photo is from 2007). Also the standard has been raised to "2.0" and received a near double boost in mhz, so for a version 1.1 link this is fine.

I would have done the as you suggest, if not for the fact that I needed the clearance so that it would fit in a PCI-Express x1 slot and the traces on the low-profile card were running through that area (I also managed to cut the +12v lead to the DDR2 power circuitry hidden on an internal power layer, but reconnected it externally).

Originally Posted by MazdaMatt

nice fix add some hot glue for longevity! Why on earth did you attack it with a power tool?

To sum up, PCI-e buses are teamed serial connections comprised of 1 to 32 "links" (desktop PC's have at maximum 16 links per connector http://www.naplestech.com/shopcart/bus_speeds.asp ). I wanted to hook up multiple displays with cheap readily available cards (and not saturate my PCI bus).

I learned that the PCIe standard auto-negotiates links and determined that I could operate a card on a single link. If I had any motherboards with a x4 connector I would have likely tried that, but x1 is the "standard".

Now that we are way off topic, I guess if Paul needed any SMD soldering done I could help out, but I am in California so it isn't the quickest way.

[motor_control]

Originally Posted by dcb

just FYI, Here is an AVR paper on hall effects and BLDC, it really is trivial stuff, not worth jumping ship for. And doesn't introduce proprietary tools into an open source project (always a red flag):
http://www.atmel.com/dyn/resources/p...ts/doc2596.pdf

They use a mega88

I suggest to use AVR447 (ATmega48) or AVR449 (ATtiny261) appnoute
"Sinusoidal BLDC control w PID" - Atmel Corporation - Industry Leader in the Design and Manufacture of Advanced Semiconductors

Our chinese frends use AVR447 in controller for "HULONG" electric bycircle BLDC HUB motor.

[NiHaoMike]

Originally Posted by nubie

To sum up, PCI-e buses are teamed serial connections comprised of 1 to 32 "links" (desktop PC's have at maximum 16 links per connector NTI--PCI vs PCI Express / Bus Speeds ). I wanted to hook up multiple displays with cheap readily available cards (and not saturate my PCI bus).

I learned that the PCIe standard auto-negotiates links and determined that I could operate a card on a single link. If I had any motherboards with a x4 connector I would have likely tried that, but x1 is the "standard".

A better solution is to just take a piece of bare wire (AWG22 or so), heat it up with a soldering iron, and use it as a hot knife to open the back of the slot. Then you don't need to modify the card at all.

[nubie]

Originally Posted by NiHaoMike

A better solution is to just take a piece of bare wire (AWG22 or so), heat it up with a soldering iron, and use it as a hot knife to open the back of the slot. Then you don't need to modify the card at all.

If you go to my photo album you will see that I did cut out the back of a PCIe x1 as well. It was the first step I took in trying the mod.

I figured it was better to modify a ~$20 video card than a ~$100 SLi motherboard (two x16 slots, and some x1 slots), so I can have 6 or more screens on one PC.

Also this card can be plugged into any motherboard instantly without voiding the motherboards warranty. As I have done several times already.

Honestly I am tired of discussing this, I did it two years ago and was fully aware of what I was doing.

In case you were wondering why, I realized that my single core PC could play back 3 HD streams simultaneously, and multi-core processors were becoming mainstream.

Also if you want to look into it there are several companies that will let you have multiple users and sessions on one machine, and I didn't care for PCI video cards as mentioned (they are 3 times the cost of the same chip on a PCIe bus, and getting more expensive all the time), not to mention the entire PCI bus is shared bandwidth and interrupts.