Static Electricity

TL

I'm using a PEK in our lab to drive an experiment and every time I look at the thing the propeller resets. I connected the PEK ground to the experiment ground, and then connected both to a good earth ground. That helped a little, but not much.

Any good suggestions for protecting a PEK from static electicity?

-TL

cgracey

I can't figure out what a PEK is. I tried Google and Wikipedia. What is this PEK?

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Chip Gracey
Parallax, Inc.

rjo_

Chip,

Thanks for asking-- I thought TL was talking about the Propeller Education Kit... but when I reread his question-- that doesn't appear to be the case.

While TL has your attention, please allow me to ask a question, without starting a new thread, which pertains to the conversation in a recent thread by Graham about cordic methods.

My question is this: Are the ROM contents of the next version of the Prop open for public discussion?... If not, what would someone have to do to place a special order? The methods I'm talking about would obviate the need for the current sin and log tables in ROM.

Thanks

Rich

TL

PEK == Propeller Education Kit

We prototyped the controller for an expermental device using a BS2pe, and I am testing its performance by faking user/system inputs using a PEK.

BTW: I don't like the PEK modular breadboards vs. the "Professional Development Board" breadboard. The PEK breadboards seem to need much longer leads that the other boards, and they don't grab some components well. I keep finding things with broken continuity.

-TL

DogP

I've got pretty much the same problem with my DIP prop in a solderless breadboard... if I have any sort of static charge and get near it, it resets. Especially if I touch the metal frame of the board (which isn't connected to any part of the circuit). So, I just stay away from it [noparse];)[/noparse] .

Another problem, maybe related is if I have the serial cable plugged into my laptop and also have my AC adapter plugged into the laptop, when I'm working w/ the TV output I get a rolling wave through the picture and a loud hum, even though I don't have any audio input connected. So I either have to work off my laptop battery, or I mute the TV and ignore the wave. I use a real serial cable with the transistor circuit, not the USB adapter, so it might not do it w/ the prop plug.

Pat

TL

I was able to corner some sparkies over here for 90 seconds to get some advice.

I've added a 1k pull up resistor between RES and Vdd.
Fixed 95% of the troubles.

I've added a 0.01 uF cap between RES and Vss.
Hafta see if that fixes the remaining 5%. Unfortunately, the propeller took >90 minutes to fail without the cap, so it might take a long time to see if we're 100% good.

-TL