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R4 and R7
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R4 and R7

by ogogon on Wed Aug 08, 2018 10:26 pm

Greetings, colleagues!

Tell me, why in USBtinyISP are applied resistors R4 and R7?
The idea is that the buffer 74AHC125N is so well coordinated with the bus.

What are these resistors for?

Ogogon.

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Re: R4 and R7

by adafruit2 on Sun Aug 19, 2018 12:03 pm

these are resistors to prevent damage to the 74hc125 in case they are set to outputs from the Arduino side after the chip is programmed.

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Please be positive and constructive with your questions and comments.