LENA-R8 series - System integration manual
UBX-22015376 - R02
Product testing
Page 111 of 116
C1-Public
In addition, module AT commands can be used to perform functional tests on digital interfaces, as for
example (for more details about AT commands, see the u-blox AT commands manual
•
communication with host controller can be checked by AT command,
•
communication with SIM card/chip can be checked by dedCPIN read command,
•
communication with external I2C devices can be checked by dedicated I2C AT commands,
•
audio interface functionality can be checked by dedicated AT+UPAR=2 command, enabling audio
loop for test purposes
•
GPIOs functionality can be checked by dedUGPIOC AT command, etc.
Please contact the u-blox office or sales representative nearest you for further guidelines about OEM
production testing guidelines.
5.2.2.1
“Go/No go” production tests for integrated devices
A “Go/No go” test is typically performed to compare the signal quality with a “Golden Device” in a
location with excellent network coverage and known signal quality. This test should be performed
after data connection has been established. AT+CSQ is the typical AT command used to check signal
quality in term of RSSI (for more details, see the u-blox AT commands manual
).
☞
These kinds of test may be useful as a “go
/
no go” test
, not for RF performance measurements.
This test is suitable to check the functionality of communication with the host controller, the SIM,
and the power supply. It is also a means to verify if the parts at antenna interface are well soldered.
5.2.2.2
Functional production tests providing GNSS RF operation
The best way to test the GNSS RF functionality is with the use of a Multi-GNSS signal generator, as it
assures reliable and constant signals at every measurement.
u-blox recommends the Spirent GSS6300 Multi-GNSS signal generator (
Guidelines for GNSS RF functionality tests:
•
Connect a Multi-GNSS generator to the OEM product.
•
Choose the power level in a way that the “Golden Device” would report a C/No ratio of 38
-40 dBHz.
•
Power up the DUT (Device Under Test) and allow enough time for the acquisition.
•
Read the C/No value from the NMEA GSV or the UBX-NAV-SVINFO message (e.g. with u-center).
•
Compare the results to a “Golden Device”.
5.2.2.3
Persistent configurations
The modules are delivered by u-blox with predefined factory-programmed settings that can be
changed using AT commands according to application-specific requirements. Some settings are
persistent, stored in the module's non-volatile memory, and re-used at any subsequent reboot. Among
these
, for example, there are the UART interfaces’ baud rate, frame format, flow control, etc., the
greeting text, the MNO profile, the APN for Internet connectivity, etc. (For more details, see the AT
command manual
After verifying the proper assembly of the module and related parts on the application device, execute
a persistent configuration setting phase in OEM production line, configuring the module according to
the intended use in the specific application, as the persistent configurations are intended to be set
only once and then re-used at any subsequent reboot.
During the persistent configuration setting phase, it is recommended to configure the baud rate,
frame format, flow control and any other settings for the serial UART interfaces according to the use
case. It is also recommended to configure the greeting text, the MNO profile and the APN for internet
connectivity, etc.
