User Manual

Module Specification
NO. AT357HP
TITLE:
Module, ZigBee, 17.9 x 24.9 x 2.75mm, 51 I/O, Edge Castellated, SMD
REVISION DATE: 8 April 2013 ISSUE: O PAGE: 17 of 27
• UART (Universal Asynchronous Receiver/Transmitter)
UART pin
Module Pin Number
GPIO Port
TXD
25
PB1
RXD
26
PB2
nCTS
14
PB3
nRTS
15
PB4
Table 9: UART Pins
Figure 9a. Host uC to AT357 module via UART Interface
AT357 module can interface UART to external serial device (for example RS-232) through a
level shifter (SP3232EBCN from Sipex).
Figure 9b. AT357 module to external UART device
AT
357
PB1
PB2
PB3
PB4
Level Shifter
TXD
RXD
nCTS
nRTS
DB9
Connector
Host uC
GPIO
TXD
RXD
AT357
nRESET
PB2
PB1