HUAWEI ME909s Series LTE Mini PCIe Module
Hardware Guide
Description of the Application Interfaces
Issue 02 (2016-09-07)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
24
Table 3-5
UART interface signals
Pin
No.
Pin Description
Pad
Type
Description
Parameter Min.
(V)
Typ.
(V)
Max.
(V)
3
UART_CTS
I
UART clear to send
V
IH
1.17
1.8
1.98
V
IL
–0.3
-
0.63
5
UART_RTS
O
UART request to send
V
OH
1.35
1.8
1.98
V
OL
0
-
0.45
17
UART_RX
I
UART receive data input
V
IH
1.17
1.8
1.98
V
IL
–0.3
-
0.63
19
UART_TX
O
UART transmit output
V
OH
1.35
1.8
1.98
V
OL
0
-
0.45
3.5.2
Circuit Recommended for the UART Interface
Figure 3-9
Connection of the UART interface in the ME909s Mini PCIe module (DCE)
with the host (DTE)
UART_TX
UART_RX
UART_CTS
UART_RTS
Module
(DCE)
Application Device
(DTE)
RXD
TXD
CTS
RTS
The UART cannot wake up the module from the sleep status, and you can pull up the
WAKEUP_IN signal for 1s instead.
The level of RS-232 transceivers must match that of the the ME909s Mini PCIe module.
3.6 USB Interface
The ME909s Mini PCIe module is compliant with USB 2.0 protocol. The USB interface
is powered directly from the VCC_3V3 supply. The USB input/output lines are