Doc. No: Unex-QSG-21-003
30/30
A printed version of this document is an uncontrolled copy
© 2023 Unex Technology Corporation – Company Confidential
12.
Troubleshooting
12.1.
Repetitive Resetting When Using 3.3V Single Voltage
Supply
Although a SOM-300 family module is capable of using 3.3V single voltage supply, the
stability is still largely dependent on the actual design of the motherboard 3.3V rail. If the
3.3.V rail impedance is not low enough, the transient current drain during RF transmission
will cause a voltage dip, and hence triggering a system reset.
If repetitive resetting happens when mounting on an off-the-shelf 3.3V mPCIe slot,
please consider supplying 5V power from J1.1 instead.
12.2.
No Response After Applying Power
This phenomenon may come from multiple causes. Please follow the steps below to
check each one of them:
1
Check if the 5V/3.3V power have been properly supplied by your motherboard.
2
Check if the SW1.1 setting matches your hardware configuration.
3
Check if the SW1.8 setting is at ON (Boot from NAND) position.
4
Connect the UART console to your host.
4.1
If you have a design-in UART interface in mPCIe P17/P19, make sure to keep
the SW1.2/SW1.3 at ON position.
4.2
If you do not have design-in UART, please connect the I/O cable for UART
interface and keep the SW1.2/SW1.3 at OFF position.
5
Check if the RNDIS driver has been properly installed on your host system.
6
Check if the IP address 192.168.1.1 has been assigned to another network interface
other than the RNDIS interface. If it has already been assigned, it is required to
perform either of the following operations:
6.1
Change the IP setting of that network interface and leave 192.168.1.1
available for the SOM-300 family RNDIS interface.
6.2
Change the SOM-300 family RNDIS IP address setting. Please refer to the
C
HANGING
S
YSTEM
IP
A
DDRESS
section in Unex’s documentation, which can
be found in Unex’s software release package.
