Is there any particular reason why MicroChip would NOT include in the datasheet for the MCP23016 a little diagram of pull-up resistors on the data and clock lines?
Who knows how long this has been working...
Robert
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Is there any particular reason why MicroChip would NOT include in the datasheet for the MCP23016 a little diagram of pull-up resistors on the data and clock lines?
Who knows how long this has been working...
Robert
My Creality Ender 3 S1 Plus is a giant paperweight that can't even be used as a boat anchor, cause I'd be fined for polluting our waterways with electronic devices.
Not as dumb as yesterday, but stupider than tomorrow!
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Hmm, I have a feeling the pull-up resistor is more a requirement for the PIC 16F877 than for the MCP23016...
Robert
My Creality Ender 3 S1 Plus is a giant paperweight that can't even be used as a boat anchor, cause I'd be fined for polluting our waterways with electronic devices.
Not as dumb as yesterday, but stupider than tomorrow!
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4K7 pull-up's ARE required on the I2C lines.
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regards
Ralph
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There are only 10 types of people:
Those who understand binary, and those who don't ...
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Hmm, ok. I've gone through the datasheet more times than I can remember, but I never saw any mention of PU resistors on the clock/data lines. Is there any mention in it? Or are we 'expected' to know better?
The only reason I thought of them is from reading the PBP Pro manual.
Robert
My Creality Ender 3 S1 Plus is a giant paperweight that can't even be used as a boat anchor, cause I'd be fined for polluting our waterways with electronic devices.
Not as dumb as yesterday, but stupider than tomorrow!
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If you put a scope on your I2C Bus, you would have realised the waveform didn't meet the specification of Table 2-5 in the Datasheet. Some devices do not require PU Resistors, PICs do... the clue could also have been found in the PBP manual I2C commands where an example schematic is given connecting to an external EEPROM. 4K7 is a good value when connecting one or two slave devices with a relatively short track between them. You need to drop this value for more devices or greater track capacitance. Refer to Raph's pointer to the I2C Bus Spec.
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Yup, like I said, that's exactly where I found the answer.
Things worked great, until I got cocky.
Yeah, I also noticed that more devices screws up stuff. At least I have Ralph's link to help me out to figure the correct resistance value.
Robert
My Creality Ender 3 S1 Plus is a giant paperweight that can't even be used as a boat anchor, cause I'd be fined for polluting our waterways with electronic devices.
Not as dumb as yesterday, but stupider than tomorrow!
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