PMODACL

The PMODACL is a 3 axis digital accelerometer module powered by the Analog Devices ADXL345. The PmodACL uses a standard 12 pin connector and can communicate via SPI or I2C. A pull up resistor on the slave select line keeps the ADXL345 in I2C mode unless the host drives the line low, in which case the device will communicate via SPI. All communications with the device must specify a register address and a flag indicating whether the communication is a read or a write. This is followed by the actual data transfer. Device configuration is performed by writing to control registers within the device. Accelerometer data is accessed by reading device registers. The SPI interface standard uses four signal lines. These are slave select, master out slave in, master in slave out and serial clock. The I2C interface standard uses two signal lines. These are I2C data and serial clock. These signals map to the serial data and serial clock respectively on the ADXL345.