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So what you are saying is that I just need to make 8 entries and not 8 for each reed?<p>Just so you understand the cicuit, the reeads are all set, I'm going to break the connection with a PNP transtior or a NAND gate for each reed. This is why I need this pattern.<p>sw 1 11000001 sw 2 11100000 sw 3 ...

Hi there:<p>I started editing the buffer of a blank chip. It a 512K, I ran into my first snag!<p>The Screen looked like this <p>ADDRESS 0 1 2 3 4 5 6 7..F 00000000 00000010 00000020 00000030<p>I edited across, and I wonder if that was correct because your offsets were only single digits<p>ADDRESS 0 ...

Hi there:<p>I'm going to give it a try today. I forgot about keeping the unused pins low, thanks for the reminder.<p>When your talking about setting /EO and /EO low, your saying when its in the curcuit right. Not in the programmer?<p>BTW Eprom I have are 512K, I think this should not be a problem, b...

One more question comes to mind. Which pins to I connect the encoder to. Well, what are the names of the pins? <p>I checked out the spec on the 27c16 chicp, My guess is Pins A0-A2. And to enable the outputs I need to make /EO high as well as /CE to enable Chip logic!<p>Is that right? Thanks

Thanks for this, it does clean up what needs to be done, but I've never messed with a programmer before and I will be bringing this to someone, that gets files and just burns eproms.<p>I'm not sure if She knows how to do this either. It would be really great if I could get a procedure (kind of an ov...

I've been doing some serious researching to your suggestion.<p>I guess the confusing point is that what would I edit? <p>I read in the eprom, make changes with an editor (I'm guessing) I have a good Hex editor at work and then Burn those changes?<p>I guess I need a little more of an explanation, -so...

I've been looking at the 1 of 8 decoder that might do the above function, however I'm still confused and I wonder if someone can help me understand something.<p>I checked out the data sheets on this and checked the truth table, what was weird was the 1 of 8 decoder has 8 outputs however only one of ...

Could someone tell me if a mux/demux would work to select a setting on the rotary switch (1-8) and then on the demux side get the output described above?<p>example<p>Switch select 8 = 00111000<p>Thanks
-paul

Gorgon:<p>That is something I think I am looking for. The logic chip would drive the gates on a PNP transitor or it could drive the b side of a NAND gate. It took me a while to understand it but your right all I'm looking to do is set a pin (3 pins) high based on a switch setting.<p>I guess the diff...

WOW din't know you could "write" your own logic. What is the language? I do have access to an eprom burner. I might want to try this after I get this system down, unless you can suggest a quick tutorial that I can get.<p>The thing is, logic cicuits at basic, require 1 output and 2 inputs. ...

yeah:<p>One of the reasons why I picked this site for help, was that many of you (if not all) are more adept in electronic circuitry than I am. I mean, if I stayed with it when I was younger I probably would know what a decoder does, I'm just finding out about these chips now. I find no references t...

Thanks.<p>You were right! Re-forcusing was what I needed to do. I got so wraped up in logic circuits that I forgot the real purpose of the circuit. I came up with a double switch. Basically as you know the reeds are a switch which when activated (lack of a better word) will allow voltage to flow. I ...

Thanks For all the responses. Remember when I said I was having difficulty imagining what to do. I got the pattern reversed. The circuits are on intially, and when the selected reed is activated the ciruits are opened.<p>I know this changes things but how?<p>Thanks again<p>-paul

Hey there All:<p>I need a little help, At least a direction to point in. My background is a little limited in electronics DIY-fer and a little high scool electronics class.<p>I'm trying to build a circuit that has 8 sensors, nothing fancy just reed switches. When the reeds close, I need them to comp...

Sorry, I know this is a stupid question, but can someone please tell me how one would place a standard PCB relay on a breadboard? The common pin seems a bit out of place to fit into a slot.<p>Thanks
paul