Manual IC creation!

Includes Atari 2600, Nintendo 8-bit, Sega Master System, MSX and more!

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demonofaj
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Manual IC creation!

Post by demonofaj »

I noticed that Ben used resisitors in the signals coming out...

Like he wired a reistor to signal up, then out the other end came tactile pushbutton switches. Are the resistors necessary?
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usbcd36
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Post by usbcd36 »

Yeah, the controller needs them to function. I don't know the exact details, but I can infer that either a) the system would reset if they weren't there and/or b) the chip would be fried from having that much current go through it.
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Post by marshallh »

usbcd36 wrote:b) the chip would be fried from having that much current go through it.
Yeah, they're either pull-up or pull-down resistors that reduce the current to the logic levels needed by the chip(s). You'd likely toast quite a few ICs if you forgot them.
Also, the exact value doesn't matter. It can be anywhere from 5Kohm to 20Kohm. Just don't omit it.
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Post by SgtBowhack »

Yep, that's right. Plus it's just generally bad to have "floating circuitry" even if the amperage was acceptable.
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Post by demonofaj »

To clarify my question.....for say the controller? That's my main confusion, would I need a resistor from say 'up' to be a bridge between up and the button?
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demonofaj
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Post by demonofaj »

Boomp-pre-engineered zings from Verbalwagon.
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