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Is the LED buffer on the QuickStart good enough to use pins with a RC delay circuit? — Parallax Forums

Is the LED buffer on the QuickStart good enough to use pins with a RC delay circuit?

Duane DegnDuane Degn Posts: 10,588
edited 2011-06-16 20:09 in Propeller 1
I'm working on a project using a QuickStart board. I want to log temperatures using several thermistors.

I plan to use a RC decay method with the thermistors to sense the temperature.

I figure if I were to put a capacitor (0.01uF) on any of the pins used by the touch pads, it would pretty much disable the touch pads (or would it make them better?).

How about the LED pins? I know they are buffered (with a 74HC541). Is the buffer good enough not to interfere with reading the thermistors using a RC delay? (I'll look at the 74HC541 data sheet. I'm not sure if I know enough to find the answer to my question there.)

I plan on using multiple thermistors. Possibly eight. It would nice to keep the other pins free for other devices.

Duane

Comments

  • Duane DegnDuane Degn Posts: 10,588
    edited 2011-06-16 20:09
    I did some tests and it appears the buffers are good enough to use the pins with a RC delay circuit.

    I go into more detail in post #8 of my QuickStart project thread.

    Duane
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