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Need help designing a load selector!
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MarkF:

--- Quote from: WyverntekGameRepairs on May 29, 2020, 09:30:51 pm ---Wait a sec! Hol up. What if we could omit the BDC completely? Here’s my thought: Use the bit shift register itself. Pressing the button sends a clock pulse, causing the output to shift to the next bit in the sequence. We just need some way for the register to get the initial data pulse we need, and let it be able to send the pulse again after the bit reaches a certain point.

--- End quote ---

Bingo!   You have the idea and my two failed attempts at it to get the initial bit for just one button press.

Here's my last attempt if this counts to five.  It is a decade counter after all (÷2 and ÷5).,
Hopefully, it counts: 0, 1, 2, 3, 4, 0, etc and we can use the '4' to start another 'high' through the shift register.



Timing:

WyverntekGameRepairs:
Whoooo! Here we go, bbing this one now... wish me luck.
WyverntekGameRepairs:
Aaaaand unfortunately nothing.
I am thinking that my resistors aren’t a good rating. I’m also using 6v regulated, but a single volt shouldn’t do any harm as these are rated from -0.5V to +18V according to the data sheet.

I have the LED’s resistors at a value of 4.7k. What do you suggest for the resistors on the switch?
MarkF:
The SN74196 can ONLY handle 5V.  Check the datasheet: It may go to 5.5V max.
You have a mixture of CMOS and TTL logic listed.

Your resistors are far to big.
   R = V / I

   R = (5 - 1.5) / 20mA = 175Ω

Let's start with 200Ω.  Each LED color will have a different Vf so you will need to tweak each to get the intensity to match.  The RGB LED may NOT need a resistor (check its datasheet).


Connect each LED to 5V through 200Ω to test each before connecting them to the circuit.
WyverntekGameRepairs:
WAIT WAIT WAIT
I found a 74LS00 and 74LS20N - NAND gates!!
Maybe this will make things easier? Unless this works, that is, in which case we won’t need these. But if it doesn’t work, we now have some NAND gates we can use.
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