User Manual

SIM900 EVB User Guide
SIM900-EVB_UGD_V1.01 13 08.12.2009
3.6 Operating Status LED
Figure 9: StatusLED
Working state of status LED as list:
Name Description STATUS
Q1 VBAT ON/OFF indicator
Bright：VBAT ON;
Extinct: VBAT OFF
Q2 GSM part status indicator
Bright: Module runs normally
Extinct: System is powered down or module runs
unconventionally
Q3 GSM_NET status indicator
Blinking at a certain frequency according various GSM net status