Connecting OLED + Baro Sensor to I2c
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deejayspinz
- Posts: 23
- Joined: Thu Feb 20, 2014 12:01 pm
Connecting OLED + Baro Sensor to I2c
Can anyhow tell me how to wire up an OLED and Baro Sensor (both are I2c) together to a HK NanoWii. Trying to understand how you wire up the 2 sensors in parallel to the system and how the are uniquely identified in MultiWii.
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deejayspinz
- Posts: 23
- Joined: Thu Feb 20, 2014 12:01 pm
Re: Connecting OLED + Baro Sensor to I2c
Answered my own question. Wire all SCL's together, and all SDA's together. Just have to figure out resistor values for pullups on both lines.
Re: Connecting OLED + Baro Sensor to I2c
Depending on the board you are using the Pull-ups may already be there. See these schematic:
viewtopic.php?f=6&t=1337&start=20#p12026
Use your DVM and measure the resistance from each I2C line (SDA & SCL) to VCC (either at a +5V pin or the +3.3V on the regulator output.
If there are not pull-ups then start with 10k Ohm and try 100kHz clock. If it does work reduce the resistor values to 4.7k Ohm.
Once working then try setting the I2C speed to 400kHz. If that doesn't works then set back to 100kHz.
viewtopic.php?f=6&t=1337&start=20#p12026
Use your DVM and measure the resistance from each I2C line (SDA & SCL) to VCC (either at a +5V pin or the +3.3V on the regulator output.
If there are not pull-ups then start with 10k Ohm and try 100kHz clock. If it does work reduce the resistor values to 4.7k Ohm.
Once working then try setting the I2C speed to 400kHz. If that doesn't works then set back to 100kHz.