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Bruce Bates
08-26-2006, 02:03 AM
Folks -

On the new SX28 Proto Board, what is the point or the purpose of having the DIP-28 socket on there which seems to overlay or surround the installed SMT SX-28 chip on the board? If you blow up the SMT SX-28 chip, the board is not lost?

Lastly, is there a schematic of the SX-28 Proto Board floating around somewhere? It's not on the product page, where I would normally expect it to be.

TIA

Regards,

Bruce Bates

Chris Savage
08-26-2006, 03:42 AM
Bruce,

ии The DIP pads are there in case you want to remove the SS part and put in a ZIF socket.и With a ZIF socket you could drop in SX28 DIP parts for whatever purpose you may need.и As for the schematic, we're looking into that.и I hope this helps.и Take care.

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Chris Savage
Parallax Tech Support
csavage@parallax.com (mailto:csavage@parallax.com)

Loopy Byteloose
08-26-2006, 05:31 PM
Ah Ha!, I can finally use my 75Mhz crystals with an SX28 and save my SX52 boards for when I really need the ports or memory, not jsut the speed.

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"If you want more fiber, eat the package.и Not enough?и Eat the manual."ииииииии


ииииииииииииииииииии Tropical regards,иииии G. Herzog [и黃鶴 ]иin Taiwan

Bruce Bates
08-26-2006, 07:30 PM
George -

Don't be a chicken! Grab a 100 MHz crystal and some ice cubes http://forums.parallax.com/images/smilies/smile.gif

Regards,

Bruce Bates

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Robert Kubichek
08-27-2006, 12:05 AM
Chris Savage (Parallax) said...
Bruce,

The DIP pads are there in case you want to remove the SS part and put in a ZIF socket. With a ZIF socket you could drop in SX28 DIP parts for whatever purpose you may need. As for the schematic, we're looking into that. I hope this helps. Take care.


Ok, that brings up a question...

Can a person get the board without the SS mounted, to do just that???
http://forums.parallax.com/images/smilies/idea.gifIt would make a great programer board, besides other things. http://forums.parallax.com/images/smilies/yeah.gif

Bob http://forums.parallax.com/images/smilies/scool.gif

Loopy Byteloose
08-27-2006, 12:07 AM
I suppose Parallax could sell you a board without the SX28 at the same price - just populated with the other components.и But why not pull the chip off and save it for when you really want to get tiny?

I would prefer 3.3volts at 75Mhz, but the TTL oscillator is rated for 5 volts and I have a funny feeling no one really wants to manufacture a 3.3volt version.и [Just look at how the Propeller got to 160Mhz with an 8Mhz crystal].

Still, the TTL oscillator is nice for much greater frequency stability regardless of the speed.и It looks like the new SX28 board is 4 layer too.и Am I correct?


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"If you want more fiber, eat the package.и Not enough?и Eat the manual."ииииииии


ииииииииииииииииииии Tropical regards,иииии G. Herzog [и黃鶴 ]иin Taiwan

Chris Savage
08-27-2006, 05:43 AM
Robert Kubichek said...(trimmed)
Ok, that brings up a question...Can a person get the board without the SS mounted, to do just that???
Robert,

ии No, the boards come with the chip on them.и It is up to the customer to remove them if they should so choose.и Take care.

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Chris Savage
Parallax Tech Support
csavage@parallax.com (mailto:csavage@parallax.com)

StarMan
09-01-2006, 01:24 AM
Is there a part number for the ZIF socket?

Chris Savage
09-01-2006, 02:48 AM
Digi-Key has several part numbers for ZIF sockets depending on brand, style and whether or not you want gold plated contacts.и You'll need a standard 28-pin DIP ZIF Socket (.600").и I hope this helps.и Take care.

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Chris Savage
Parallax Tech Support
csavage@parallax.com (mailto:csavage@parallax.com)