Quectel Wireless Solutions Company Limited 201404UC15M User Manual
UMTS/HSDPA Module Series
UC15 Mini PCIe Hardware Design
UC15_Mini_PCIe_Hardware_Design Confidential / Released 19 / 40
Table 6: Pin Definition of the UART Interface
The UART interface supports 300, 600, 1200, 4800, 9600, 19200, 38400, 57600, 115200 and 230400bps
baud rate. The default is 115200bps. Autobauding is not supported. This interface can be used for data
transmission and AT communication.
UC15 Mini PCIe is designed as the DCE, and the DCE-DTE connection of UART interface is shown as
below.
Figure 4: The DCE-DTE Connection of UART Interface
The following figure is an example of connection between UC15 Mini PCIe and PC. Since the UART
interface does not support the RS-232 level, RS-232 level translator IC must be inserted between module
and PC. The following figure shows the reference design of RS232 level match circuit.
Pin No.
Pin Name
I/O
Description
Power Domain
11
UART_RX
DI
UART receives data
3.3V
13
UART_TX
DO UART transmits data
3.3V
17
UART_RI
DO UART ring indicator
3.3V
23
UART_CTS
DI
UART clear to send
3.3V
25
UART_RTS
DO
UART request to send
3.3V
31
UART_DTR
DI
UART data terminal ready
3.3V
33
UART_DCD
DO
UART data carrier detection
3.3V