Neo_M680 GPRS Module Hardware User Guide
Copyright © Neoway Technology Co., Ltd
16
3.1.5 RESET
You can reset the module by keeping the RESET pin low level for more than 100 ms. The pin is pulled up by
an internal resistor and the typical high level is 2.8 V. The RESET pin can be left disconnected if not used. If
you use 3.3 V IO system, you are advised to separate it by using triode. Please refer to Figure 3-11.
Figure 3-11
Reset circuit with triode separating
3.2
UART
Table 3-2
UART
Signal
I/O
Function Description
Remarks
RTS
DI
Request to send
CTS
DO
Clear to send
URXD
DI
UART data receive
UTXD
DO
UART data transmit
UART is used for AT commands, data sending/receiving, firmware updating, etc. Figure 3-12 shows the
signal connection between the module (DCE) and the terminal (DTE).
Figure 3-12
Signal connection between DCE and DTE
RESET
VDD_EXT
4.7K
47K
GPRS Module
DCE
URXD
UTXD
DTE
UTXD
URXD
RTS
CTS
CTS
RTS
