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[on:]

I have just one thing to say (it's at the bottom of this post).

Since I was a teenager fooling around with electronics, I've had trouble understanding transistors.  Not the big things: they can amplify; they can act like a switch.  But the little things: forward-this; leakage-that.

Lately, I've been performing a "run dead" test.  I have an ATtiny processor running from two AA batteries.  It sends status information to an Arduino running from USB power.  The goal is to run the test until the batteries are dead.  As expected, when the batteries reached about 2.3 volts, the ATtiny was no longer able to communicate reliably.  The ATtiny Sketch was running fine.  The output voltage just wasn't enough to reliably trip the Arduino's inputs.

Time for a level shifter.  Only, I don't have one.  Time to make a level shifter.  Only, I don't have a clue how to build one.  And then I remembered this...
http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1245734119/all

I reread that thread and everything clicked!  I now have a pair of low-voltage to 5V transistor-switches.  I was even able to tweak the resistors without blowing up anything.  A few more transistor-switches under my belt and I may be able to fly solo (not have to use reference material)!

So, I have just one thing to say ... THANK YOU!  To retrolefty, Grumpy_Mike, EmilyJane, and pwillard ... THANK YOU!

[Reply #1 on:]

Well, sorry nobody replied but I do have to say I'm glad to see it wasn't just my thank you post that got ignored. (See page 2.) I was starting to take it personally but I guess people just aren't very chatty on this forum.

[Reply #2 on:]

I think these two threads have one thing in common, they are thankyous and therefore don't ask a question.

I've started a couple of threads that asked a specific question that received not a single response  , so don't feel too bad.

______
Rob

[Reply #3 on:]

 I missed a bunch of posts over the weekend, out of town Sunday and trying to get an interrupt working the rest.

Was there ever a schematic posted for the level shifter,  is it just a variation on the RS232 level changer on the Serial Arduino, or what?

[Reply #4 on:]

Thank you for the sentiments biocow.  I actually didn't expect a reply¹.  I suppose someone could have said something like, "glad you have it working" or "glad to have helped."  But those things are implied by the fact that folks were willing to help.

I was starting to take it personally but I guess people just aren't very chatty on this forum.

The level of chattiness seems to ebb and flow.  The lack of response to your post can simply be timing. 

The other problem is that, if there are no responses within the first few days, the message gets pushed down out of sight.  Once out of sight, someone who would have replied won't find it to reply.

I think these two threads have one thing in common, they are thankyous and therefore don't ask a question.

I agree.  About the only thing that can be said to a "thank you" is "you're welcome".  The "you're welcome" is implied by the fact that help was provided so it seems rather redundant.

I've started a couple of threads that asked a specific question that received not a single response  smiley-cry, so don't feel too bad.

Dang it!  There's an email from you sitting in my inbox that needs a reply.  Sorry about that Graynomad.

Was there ever a schematic posted for the level shifter

No schematic.

is it just a variation on the RS232 level changer on the Serial Arduino, or what?

Yes.  (I'm embarrassed to say I never thought to look at the Serial Arduino for guidance)  Two resistors and a 2N3904 --> a one bit inverting level shifter.


¹ Especially not from EmilyJane who, very unfortunately, appears to have wandered off.

[Reply #5 on:]

Well, glad to see that you got it working

[Reply #6 on:]

The level of chattiness seems to ebb and flow.  The lack of response to your post can simply be timing. 

True. Guess I'm just used to the other forum I frequent where someone always has something to say about everything no matter what. Though I hate the phrase, I guess "It [this forum] is what it is." A great place to do research, get questions answered and look at some really cool projects. (i.e. Grumpy Mike's latest. That's pretty awesome!)

[Reply #7 on:]

Dang it!  There's an email from you sitting in my inbox that needs a reply.  Sorry about that Graynomad.

No problems, I've answered my own questions. The '85 emulator is largely working but it will need a special core port I think and I have other projects to play with for the time being.

______
Rob