EVA-8M and EVA-M8 series - Hardware Integration Manual
UBX-16010593 - R06
Design-in
Page 12 of 47
Early Production Information
SQI Flash size of 8 Mbit is sufficient to save AssistNow Offline and AssistNow Autonomous
information as well as current configuration data. However, for EVA-M8M and EVA-M8Q to run
Firmware from the SQI Flash and provide space for logging results, a minimum size of 8 Mbit may not
be sufficient depending on the amount of data to be logged.
☞
For more information about supported SQI Flash devices see Table 18.
EVA-8M / EVA-M8 series modules have a configurable
VCC_IO
monitor threshold (iomonCfg) to
ensure that the module only start if the
VCC_IO
supply is within the supply range of the SQI Flash
device (VCC_IO is used to supply the SQI Flash). This will ensure that any connected SQI Flash memory
will be detected correctly at startup.
See the
u-blox 8 / u-blox M8 Receiver Description Including Protocol Specification [3] for setting the
iomonCfg value.
With EVA-8M and EVA-M8M modules the VCC_IO monitor threshold is set to default 1.54 V value for
using a 1.8 V Flash memory device.
With EVA-M8Q module, the VCC_IO monitor threshold is set to default 2.69 V value in production, but
may be increased to 3.0 V.
If the default value for the VCC_IO monitor threshold is not suitable it can be set according to the IO
supply voltage level (VCC_IO) in the eFuse by the Low Level Configuration.
If VCC_IO voltage 2.7 V to 3.0 V is used, send the following sequence to the module
•
B5 62 06 41 0C 00 00 00 03 1F 04 BA CF 67 FF 7F FF FF E5 95
If VCC_IO voltage 3.0 V to 3.6 V is used, send the following sequence to the module
•
B5 62 06 41 0C 00 00 00 03 1F 4F 22 4C 5C FF 7F 7F FF 8A 7C
☞
Applying these sequences result in a permanent change and cannot be reversed. An unstable
supply voltage at the
VCC_IO
pin while applying these sequences can also damage the receiver.
☞
Make sure that the
SAFEBOOT_N
pin is available for entering Safe Boot Mode. Programming the
SQI Flash memory with a Flash firmware is done typically at production. For this purpose the EVA-
M8M and EVA-M8Q GNSS modules have to enter the Safe Boot Mode. More information about
SAFEBOOT_N
pin see section 2.6.
☞
When the EVA-M8M-1 variant is attached with an external SQI flash without running a Flash
firmware, the default concurrent reception of GPS/QZSS/SBAS and BeiDou remains unchanged.
In case the Flash is also used for execution of firmware update, the default reception will be reset
to GPS/QZSS/SBAS and GLONASS. EVA-M8M-1 can be changed back to concurrent
GPS/QZSS/SBAS and BeiDou by sending a dedicated UBX message (
UBX-CFG-GNSS
) to the
module. More information see the
u-blox 8 / ublox M8 Receiver Description Including Protocol
Specification [3].
2.3
I/O Pins
All I/O pins make use of internal pull-ups. Thus, there is no need to connect unused pins to
VCC_IO
.
2.3.1
Time pulse
A configurable time pulse signal is available with the EVA-8M / EVA-M8 series GNSS modules.
The
TIMEPULSE
output generates pulse trains synchronized with GPS or UTC time grid with intervals
configurable over a wide frequency range. Thus it may be used as a low frequency time
synchronization pulse or as a high frequency reference signal.
