I have selected the I2C in the Hardware Configuration but when I transmit data nothing is visible on this pins.

If you are using our driver it is most likely, that the external circuit does not create a valid I2C bus.

In the I2C specification in chapter "7. Electrical connections of I2C-bus devices to the bus lines" you are able to find further informations on this topic.

Typical the pull up resistance is 10 kΩ for 100 kHz and 2 kΩ for 400 kHz

A basic circuit is:

See also...

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A Raspberry Pi supports multiple SPI signals, which ones are used for communication between RPi and netHAT?
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Can other expansion HAT boards be used in combination with the netHAT?
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Is other protocol fimware than PROFINET, EtherCAT and EtherNet/IP available for netHAT?
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The SYS LED of netHAT flashing alternately yellow and green, is this normal?
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How fast can be the data update cycle with an application running above netHAT?
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Where can I find API documentation about the netHAT supported protocols?
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Is there a 3D CAD model of the netHAT available?
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A netX52 chip could support multiple communication channels at a time, does the netHAT support more than one channel?
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Can I use netHAT with more than 32 bytes inputs or outputs?
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Which operating systems does the netHAT support?
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Which SD card size do I require?
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Whom should I contact if I have technical questions relating to the netHAT?
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Which power supply unit do I require?
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Where can I find documentation and further information of the netHAT module?
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Supported Flash Types netX100/500

I2C Bus