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Parallax BS2 question

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Otaku

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Hi all,
I'm working on a project that needs to isolate/evaluate individual thermocouple signals and send a go/no go result to a LED. I'd like to use just one TC amplifier circuit in this tester, so I plan to use 4051 multiplexers to index the specific TC signals to be sent to the amplifier circuit.
The 4051 needs a 3-digit logic input to go to a specific output pin and the BS2 should be able to handle this with 3 outputs that would be at either 0 or 1 (1,0,0; 1,0,1 etc) going to the logic inputs on the 4051's. I'm new to PBasic and BS2's but have many years of VBA programming experience, so learning how to code the BS2 shouldn't be too difficult. What I'm wondering is if the BS2 can be programmed to output the needed logic signals when it gets a high input from a 4017 counter, or from a 555 oscillator (the clock for the 4017). All advice is appreciated!

Gary
 
Do you really need the BS2 or could you drive the multiplexer with a counter.
 
Do you really need the BS2 or could you drive the multiplexer with a counter.

I looked into that option, but the 4051 requires a 3-part logic signal to specify the active output pin. That's where the BS2 (or a PIC) comes in. My concern here is the coding/triggering requirements of the BS2. If I can get to execute the correct outputs on a high input from the 555 clock, then no problem.
 
How about a binary counter instead of the decade counter.
 
Good article, thanks, but that looks like the 555 will run the sequence over and over until power is cut. I would need the 555 to stop after all 8 of the binary-coded outputs have run and wait for the next trigger to repeat the sequence. I can do that with the BS2, but I'm still not certain that I can get it to look for a clock input and send the correct binary code on demand. I gotta do some more homework.
 
Eight TC's. I'm using small incandescent heaters to test the junctions for polarity. The junction is heated and the mV signal goes to one of the 4051's where it's indexed, then to an amplifier and LM339 comparator, then back to a second 4051 where it's sent to the correct SCR to light a LED indicating a pass. If the mV signal results in a negative voltage, the junction fails polarity.
 
What I'm wondering is if the BS2 can be programmed to output the needed logic signals when it gets a high input from a 4017 counter, or from a 555 oscillator (the clock for the 4017). All advice is appreciated!

This should be fairly easy to do with the BS2 but what is the 4017 and 555 for? Cant you use the timing in the BS2?
Andy
 
I think you can use the DIRH and OUTH commands to generate a binary number.
 
Update - I seem to have a solution that doesn't require using multiplexing, so at this time the BS2 may not be needed.

To clarify the situation, the initial design input asked for a hardware-only design. I proceeded on that, although I argued for using one or PicAxe IC's to control and evaluate test inputs and results. This tester is to be used on a medical device manufacturing line, and the FDA/ISO requirements for software and firmware validation are pretty extensive. Using IC logic only would prevent having to go through the software V&V since everything is essentially hard-wired and can easily be verified.
 
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