LTE Standard Module Series
EC200U&EG915U_Series_PPP_Application_Note 11 / 28
When the module is powered on, if the main UART is used, set the baud rate by executing
AT+IPR=xxx;&W
. Before executing
ATD*99#
to set PPP, you must check the status of the (U)SIM card
by
AT+CPIN?
. When the (U)SIM card is ready, please periodically check the network registration status
by
AT+CREG?
and
AT+CGREG?
until the network is prepared.
1. Please ensure MCU and the module are synchronized successfully after rebooting the module. MCU
sends
AT<CR><LF>
to the module every 100 ms until it receives
OK
reported by the module. If the
main UART is used, the MCU will execute
AT+IPR=xxx;&W
to set and save the baud rate after
successfully synchronizing the baud rate.
2. Before inputting the next AT command, the MCU needs to wait for the response to the previous AT
command (such as response
OK
,
CME error
,
CMS error
). If there is no response within 60 seconds,
the module can be restarted.
3. It is strongly recommended NOT to power on/off the module frequently. If 3 consecutive dialing retries
fail, you can immediately power on/off (reset) the module for the first time. After resetting, if the dialing
retry fails, you need to wait 10 minutes for the second reset, 30 minutes for the third reset, and one
hour for the fourth reset.
4. If the MCU fails to transmit data to network after establishing the PPP connection, please check the
PPP configuration and network status and restart the module.
NOTES