[minima] Re: band switching

  • From: "Steve VK2SJA" <vk2sja@xxxxxxxxxxx>
  • To: minima@xxxxxxxxxxxxx
  • Date: Mon, 10 Feb 2014 09:43:51 +1100


>Steve, this uses just two lines.

Alright. I'll admit it. This muddle headed wombat is still very confused.

1 x Pin to pulse counter in 4017 decade counter to select band pass filter
+1 x Pin to reset 4017 decade counter to default known start state

= 2 pins

2 pins + 1 pin for controlling the low pass filter selection = 3 pins.

vs

3 pins Binary Coded Decimal (BCD) to control *both* low pass filter
selection and the output band pass filter selection.

Two different ways to arrive at the same level of control. But is it not
still 3 pins = 3 pins?

So where are we saving an IO line?

I'm probably being completely daft and missing the flaming obvious but I
just can't see it.

Help!

73, Steve.









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