NEO-M9N - Integration manual
Feature
Change
Action needed / Remarks
Digital IO
External IO isolation is required.
The ouput current of the digital IOs is
2 mA compared to 4 mA in NEO-8Q
and NEO-M8 modules, except for the
TIMEPULSE pin, which still provides
drive strength of 4 mA.
Do not drive IOs when VCC and V_IO are not supplied. Removing
the VCC supply does not isolate the IO pins of the module from
the IO pins on the host device. If the IO pins are not isolated,
the GNSS receiver may get permanently damaged when high
current is drawn from the IO pins.
Additional external pull-up resistors may be required to
increase the drive strength of the digital IO output pin or adjust
the load accordingly.
Table 28: NEO-M9N hardware features compared to NEO-8Q/M8 modules
Refer to NEO-8Q, NEO-M8, and NEO-M9N data sheets for details on performance comparison [
presents a summary of the key
software-related changes
between NEO-M9N and
NEO-8Q/M8 modules, as well as required actions during migration.
Feature
Change
Action needed / Remarks
Default baud rate
NEO-M9N: 38400 baud.
NEO-8Q/M8N/Q/J/M: 9600 baud.
Code change (optional)
Default GNSS config
NEO-M9N: GPS, Galileo, GLONASS, BeiDou, QZSS and SBAS.
NEO-M8N/Q/J/M: GPS, GLONASS, QZSS and SBAS.
NEO-8Q: GPS, QZSS and SBAS.
Code change (optional)
QZSS-IMES
Not supported in SPG 4.04 firmware.
Code change (optional)
New signal support
QZSS L1S, BDSBAS L1C/A
Code change (optional)
RF spectrum view
New message: UBX-MON-SPAN shows in-band RF spectrum
around the GNSS band. The spectrum information in this
message can be used to identify potential in-band RF
interference sources in the design.
Code change (optional)
Time pulse
The quantization error output via UBX-TIM-TP2 is no longer
supported. u-blox recommends using dedicated timing
products for precise time information.
Code change
NMEA
Supports NMEA 0183 V4.10, V4.0, V2.3, and V2.1.
NMEA V4.10 is enabled by default.
Code change (optional)
RTCM
RTCM 3.3 is supported. RTCM 2.3 is not supported.
Code change
Power-save modes (PSM)
PSM configuration options have changed. PSMCT: 4 Hz
navigation rate is not supported. PSMCT period is configured
with CFG-RATE configuration group.
Code change
Navigation update rate
Supports up to 25 Hz for all supported GNSS constellation
combinations.
Code change (optional)
Galileo return link messages
Galileo search and rescue (SAR) return link messages are
available in UBX-RXM-RLM and NMEA-Standard-RLM.
Code change (optional)
AssistNow
Simultaneous operation of AssistNow Online, Offline and
Autonomous. New AssistNow Offline data download options
are available. The time period can be limited to a resolution of
days to reduce the data package size.
Code change (optional)
Location batching
New feature that can be used to reduce power consumption
by saving navigation solutions on the receiver for up to 5
minutes and polling the solutions afterwards to a host MCU.
Code change (optional)
Configuration lock
New security feature that is enabled with CFG-SEC-
CFG_LOCK message for locking the receiver configuration.
Code change (optional)
Unique chip identifier
The unique chip identifier is available in the UBX-SEC-
UNIQID message and at startup from the boot screen.
Code change (optional)
Configuration messages
New configuration scheme using UBX-CFG-VALSET and
UBX-CFG-VALGET messages.
Code change
Table 29: NEO-M9N software features compared to NEO-8Q/M8 modules
UBX-19014286 - R07
Appendix
Page 91 of 95
C1-Public