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    BMP388: what is the maximum of slave addresses in I2C mode

    BMP388: what is the maximum of slave addresses in I2C mode

    New Poster

    In I2C mode with one master how many  BMP388 as slave can be connect  to an Arduino UNO?

    From the datasheet I understand that there are only 2 adresses possible  in I2C mode (0x76 or 0x77) as designated by bit  7 in the device address  and configured via the SDO (pin 5) port to ground or plus.

    In SPI mode, as I hope to understand well from the datasheet,  it's up to 128 BMP388 addresses.

    My questions are:

    -Am I understanding well that in I2C mode the maximum number of slaves is two?

    -Of course I can connect a lot of BMP388's in series to the Arduino, but how can I address them in I2C mode. Or should I use SPI mode?

    -Is there any documentation that makes this more clear?

    -Is there any example Arduino code for the I2C situation?

    1 REPLY 1

    Hi Barry,

    You can connect a maximum of 2 BME388 per i2c bus. The maximum amount of sensors depends on how many i2c buses you have in your system (most hosts that more than 1 i2c bus, there are also i2c bus multiplexers ICs).

    For SPI, there is not limit to the number of devices. Apart from SCK, MOSI and MOSI, one need 1 chip select GPIO pin for each slave device. the maximum number of slaves is therefore the maximum number of GPIO pins available on your host. There again, there are a variety of I/O expanders that can greatly increase the number of GPIOs for Chip Select pins.