Digi XBee3 802.15.4 User Manual

SPI operation SPI communications
Digi XBee3® 802.15.4 RF Module User Guide
37
SPI communications
The XBee3 802.15.4 RF Module supports SPI communications in slave mode. Slave mode receives the
clock signal and data from the master and returns data to the master. The following table shows the
signals that the SPI port uses on the device.
Refer to the XBee3 Hardware Reference Guide for the pinout of your device.
Signal Direction Function
SPI_MOSI
(MasterOut,SlaveIn)
Input Inputs serial data from the master
SPI_MISO(Master
In,Slave Out)
Output Outputs serial data to the master
SPI_SCLK
(SerialClock)
Input Clocks data transfers on MOSI and MISO
SPI_SSEL
(SlaveSelect)
Input Enables serial communication with the slave
SPI_ATTN (Attention)
Output
Alerts the master that slave has data queued to send. The XBee3
802.15.4 RF Module asserts this pin as soon as data is available
to send to the SPI master and it remains asserted until the SPI
master has clocked out all available data.
In this mode:
n SPI clock rates up to 5 MHz (burst)are possible.
n Data is most significant bit (MSB) first; bit 7 is the first bit of a byte sent over the interface.
n Frame Format mode 0 is used. This means CPOL= 0 (idle clock is low) and CPHA = 0 (data is
sampled on the clock’s leading edge).
n The SPI port only supports API Mode (AP = 1).
The following diagram shows the frame format mode 0 for SPI communications.
SPI mode is chip to chip communication. We do not supply a SPI communication interface on the XBee
development evaluation boards included in the development kit.

Digi XBee3 802.15.4 Specifications

General

Brand	Digi
Model	XBee3 802.15.4
Category	Control Unit
Language	English