ZOE-M8B - System Integration Manual
UBX-17045131 - R04
Contents
Page 16 of 42
Production Information
A signal change on the UART RXD pin can also be used to wake up the receiver in Power Save Mode
(see the
u-blox 8 / u-blox M8 Receiver Description Including Protocol Specification [3]).
☞
Designs must allow access to the UART and the
SAFEBOOT_N
pin for future service, updates, and
reconfiguration.
2.2.2
Display Data Channel (DDC) Interface
An I
2
C compatible Display Data Channel (DDC) interface is available for serial communication with a
host CPU.
☞
The SCL and SDA pins have internal pull-up resistors sufficient for most applications. However,
depending on the speed of the host and the load on the DDC lines additional external pull-up
resistors might be necessary. For speed and clock frequency see the
ZOE-M8B Data Sheet [1].
☞
To make use of DDC interface the
D_SEL
pin has to be left open.
☞
The ZOE-M8B DDC interface provides serial communication with u-blox cellular modules. See the
specification of the applicable cellular module to confirm compatibility.
2.2.3
SPI interface
The SPI interface can be used to provide a serial communication with a host CPU. If the SPI interface
is used, UART and DDC are deactivated, because they share the same pins.
☞
To make use of the SPI interface, the
D_SEL
pin has to be connected to GND.
2.2.4
SQI interface
An external SQI (Serial Quad Interface) Flash memory can be connected to the ZOE-M8B GNSS SiP.
The SQI interface provides the following options:
•
Store the current configuration permanently
•
Save data logging results
•
Hold AssistNow Offline and AssistNow Autonomous data
☞
The voltage level of the SQI interface follows the
VCC
level. Therefore, the SQI Flash must be
supplied with the same voltage as
VCC
of the ZOE-M8B GNSS SiP. It is recommended to place a
decoupling capacitor (C4) close to the supply pin of the SQI Flash.
☞
Make sure that the SQI Flash supply range matches the voltage supplied at
VCC
.
Figure 11 : Connecting an external SQI Flash memory
SQI flash size of 4 Mbit is sufficient to save AssistNow Offline and AssistNow Autonomous
information, current configuration data as well as space for data logging results. A larger SQI flash
size may be required for large amounts of log data.
