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: 19 of 29
• 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 13a. Host uC to AT357A module via UART Interface
AT357A module can interface UART to external serial device (for example RS-232) through a
level shifter (SP3232EBCN from Sipex).
Figure 13b. AT357A module to external UART device
AT
357
A
PB1
PB2
PB3
PB4
Level Shifter
TXD
RXD
nCTS
nRTS
DB9
Connector
Host uC
GPIO
TXD
RXD
AT357A
nRESET
PB2
PB1