PaulStoffregen / OneWire

Library for Dallas/Maxim 1-Wire Chips
http://www.pjrc.com/teensy/td_libs_OneWire.html
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CRC Check #50

Closed joaofidelix closed 4 years ago

joaofidelix commented 6 years ago

Hi. I have a DS1990A-F5 iButton.

I have some iButtons. I used a schematic where I do a pull-up with a 4.7k resistor.

1) Why do some iButtons when I use the .Search function returns that it does not find?

2) And some iButtons that returns positive from the .Search function, when will I do the CRC check, the return is always negative? Example:

if (OneWire :: crc8 (addr, 7) == addr [7]) For example: OneWire :: crc8 (addr, 7) return 255 and addr [7] return 0

Can someone help me?