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Mitch S.
03-20-2010, 04:53 PM
It has been years since I played with the Basic Stamp, but think a simple BS1·would work for what I need to do.

I have a digital recorder that I need to press a sequence of buttons to get it to the mode I want it in after power is applied so I thought maybe the Basic Stamp would work.

I have already "disected" the recorder and manually wired 3 buttons to it so I can externally control it.· The keypad is using a matrix setup so I cannot just send a high or low to it, so I though I would just use some relays controlled by pins as outputs on the Basic Stamp to do this.

If I use a small enough reed relay and clamping diode, should that be OK to protect the output pins as long as the relay is 20-25 mA?

The reason I am using a Basic Stamp is I have to push the power button for about 3 secs and then press the mode button and then press the record button to get it to the state I want it in when power is applied.· I figured a Basic Stamp would accomplish this with ease.

I was hoping I could just control the "buttons" directly with the Basic Stamp, but then I found out the buttons on the device were matrixed, so no go there.

If anyone can think of a better or easier way of accomplishing this, please let me know.

I apologise if a lot of this sort of thing has been discussed, as I have not read through all the info and forums that I have found on this site yet!

Thanks
Mitch

stamptrol
03-20-2010, 07:21 PM
Reed relays of appropriate current draw (and clamped) should work fine. I have some that draw about 15mA and have 1 A contacts. Check DigiKey.

Cheers,

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Tom Sisk

http://www.siskconsult.com
·

Mitch S.
03-21-2010, 01:34 PM
That is what I was thinking too. I even found a 7.1mA relay on there
search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=306-1063-ND (http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=306-1063-ND)
with .5A contacts @ 200VDC, but slightly expensive at $6.34

I think I will use
search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=306-1063-ND (http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=306-1063-ND)
with a coil of 10mA and a SIP package with a clamping diode built in for only $1.69. I am hoping to build the entire "project" on a 28 pin socket and/or headers.

Mitch

Post Edited (Mitch S.) : 3/21/2010 6:40:04 AM GMT