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Help identifying I2C sensor from Propel Star Wars Drone

Might be a pressure sensor like the Goertek SPL06-001. It's probably used to measure the altitude of the drone. It uses the I²C address 0x76 if the SDO pin is pulled to ground according to the ...
nanash1's user avatar
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1 vote

Can I put schottky diodes in I2C line to prevent LTC2944 from powering my circuit through SDA and SCL?

That's never going to work, and you're thing about fixing your problem in the wrong way. I2C lines need these passive pull-up resistors because the ICs on each end can only drive the signals low. Your ...
brhans's user avatar
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2 votes

Can I put schottky diodes in I2C line to prevent LTC2944 from powering my circuit through SDA and SCL?

The I2C bus interface will not work as implemented. The pullup resistors should be 2k to 3.3V not to "charge". 680k is way to big. Don't expect much current drive out of ALCC. A reference ...
RussellH's user avatar
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2 votes
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Can MUXs or their channels be sperate busses?

As far as your MCU I2C peripheral is concerned, you still have only one bus. What the TCA9548A allows you to do is select which I2C devices are connected to the bus at any given time. This is useful ...
Chintalagiri Shashank's user avatar
2 votes

Can MUXs or their channels be sperate busses?

The TCA9548A is a passive switch; all active channels are directly connected to the master bus. This means that all devices on all active channels are directly visible and accessible by the master, ...
CL.'s user avatar
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1 vote

A question about I2C resistor locations and bus capacitance

Typically, on a plain I2C bus, the bus is assumed to have signal fall (and rise) times so slow, at least compared to the bus length (maybe onboard a PCB or at most between two PCBs close to each other)...
Justme's user avatar
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3 votes
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A question about I2C resistor locations and bus capacitance

On short distances the placement of the resistors does not matter. On longer distances (which is not what I2C is for) it is typical to have resistors on the MCU side, although there is no technical ...
Maple's user avatar
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2 votes
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What determines I2C interrupt service time after address byte ACK?

It is defined by what the MCU was doing when byte is transferred, how long it takes to notice I2C interface needs servicing, and how quickly the I2C interface is serviced and ready for next transfer. ...
Justme's user avatar
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1 vote
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Using MUXs to Address Multiple Devices

So to aswer the question, the best resource how to program that chip is the data sheet. Failing that, it is a very common chip so likely some hobbyists have created blogs or Youtube videos about it, ...
Justme's user avatar
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0 votes
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How do I increase I2C/Wire Timeout on Teensy41

OK. I2C is a steep learning curve. In the hope that it might be useful to others facing the same issues I'll post an answer here with some of the things I learned. In getting up the I2C learning curve ...
Hubert B's user avatar
2 votes
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Reading multiple push-button switches on a raspberry pi using an mcp23017 over C++

Just connecting switches from the inputs of the MCP23017 to ground is not how it works. An input is usually floating, which means the voltage is not defined, which means the input state is not defined ...
Stefan Wyss's user avatar
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3 votes
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Does this board already have pull up resistors for I2C?

It is unlikely that an MCU board would have fixed I2C pullup resistors because (a) it makes the pins more difficult to use for other purposes, (b) because I2C would probably anway attempt to use ...
6v6gt's user avatar
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