User's Manual

BT900-Sx Hardware Integration Guide
Intelligent BTv4.0 Dual Mode Module
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26 CONN-HIG-BT900
An I2C interface allows multiple masters and slaves to communicate over a shared wired-OR
type bus consisting two lines which normally sit at VCC. The BT900 module can only be configured
as an I2C master with additional constraint that it be the only master on the bus. The SCL is the
clock line which is always sourced by the master and SDA is a bi-directional data line which can
be driven by any device on the bus.
IMPORTANT: It is essential to remember that pull-up resistors on both SCL and SDA lines are not
provided in the module and MUST be provided external to the module.