Uart Interface - Quectel UC20 User Manual

UMTS/HSPA/LTE Module Series
UMTS&LTE EVB User Guide
NOTE
The USIM card detection function of UMTS&LTE module is disabled by default.

3.5. UART Interface

UMTS&LTE EVB offers two UART interfaces, COM1 (Main UART port) and COM2 (Debug UART port).
The UART interface COM1 of the UMTS&LTE EVB is intended for the communication between the
module and the host application. This interface can be used for data transmission and AT communication.
The following figure shows the UART block diagram on UMTS&LTE EVB.
J401
Module
J101
COM1
U401
U403
DB9
RS232
3.0V/1.8V
Level Match
Level Translator
1.8V
RS232 3.0V
Figure 16: UART Block Diagram
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