User Manual

Module Specification
NO. AT357A
TITLE:
Module, ZigBee, 17.9 x 24.9 x 2.75mm, 51 I/O, Edge Castellated, SMD
REVISION DATE: 22 May 2013 ISSUE: O PAGE: 20 of 29
• TWI (Two Wire Serial Interface)
TWI pin
Module Pin Number
GPIO Port
SC2SDA (open drain)
17
PA1
SC2SCL (open drain)
18
PA2
Table 10: TWI Pins
Figure 14a. Host uC to AT357A module via I2C Interface
AT357A can support external I2C devices such as sensor board to provide wireless sensing
application.
Figure 14b. AT357A module to external I2C device
Host uC
Master SDA
Master SCL
AT357A
PA1
PA2