Quectel UMTS&LTE EVB - UART Interfaces (J401;J402)

UMTS/HSPA/LTE Module Series
UMTS&LTE EVB User Guide
UMTS&LTE_EVB_User_Guide Confidential / Released 30 / 44
4.8. UART Interfaces (J401/J402)
The UMTS&LTE EVB offers two UART interfaces: COM1 (Main UART port J401 and J402) and COM2
(Debug UART port).
COM1 of UMTS&LTE EVB is intended for the communication between the module and the host
application. It can be used for data transmission and AT command communication.
COM2 supports 115,200bps baud rate. It can be used for Linux console and log output.
The following figure shows the block diagram of UART on UMTS&LTE EVB.
J101
UMTS&LTE
Module
RS232
Level Match
3.0V/1.8V
Level Translator
COM1
DB9
J401
RS232 3.0V
1.8V
U403
U401
RS232
Level Match
3.0V/1.8V
Transistor Level
Translator
COM2
DB9
J402
RS232 3.0V
U402
1.8V
Figure 24: UART Block Diagram
The following two figures show the pin assignments of J401 and J402.
1
2345
12345
67
89
Figure 25: Pin Assignments of J401
Quectel
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