NINA-B1 series - System integration manual
UBX-15026175 - R16
System description
Page 10 of 63
C1-Public
1.5
System function interfaces
1.5.1
Module reset
You can reset the NINA-B1 modules by applying a low level on the
RESET_N
input pin, which is
normally set high with an internal pull-up. This causes an “external” or “hardware” reset of the module.
The current parameter settings are not saved in the non-volatile memory of the module and a proper
network detach is not performed.
1.5.2
Internal temperature sensor
The radio chip in the NINA-B1 module contains a temperature sensor used for over temperature and
under temperature shutdown.
⚠
The temperature sensor is located inside the radio chip and should not be used if an accurate
temperature reading of the surrounding environment is required.
1.6
Debug – Serial Wire Debug (SWD)
The primary interface for debug is the SWD interface. The SWD interface can also be used for
software upgrade.
The two pins,
SWDIO
and
SWDCLK
should be made accessible on header or test points.
1.7
Serial interfaces
⚠
Depending on whether NIINA-B1 is used with u-connectXpress software or open CPU based
application, the available interfaces and pin mapping can differ. NINA-B1 pin configurations and
module functions are described in the data sheet [2].
1.7.1
Universal Asynchronous Serial Interface (UART)
NINA-B1 series modules support a Universal Asynchronous Serial Interface (UART) for data
communication.
The following UART signals are available:
•
Data lines (
RXD
as input,
TXD
as output)
•
Hardware flow control lines (
CTS
as input,
RTS
as output)
•
DSR
and
DTS
are used to set and indicate system modes
The UART can be used as both 4 wire UART with hardware flow control and 2-wire UART with only
TXD
and
RXD
. If using the UART in 2-wire mode,
CTS
should be connected to GND on the NINA-B1
module.
Depending on the bootloader used, the UART interface can also be used for software upgrade. See
the Software section for more information.
The u-connectXpress software adds the
DSR
and
DTR
pins to the UART interface. These pins are not
used as they were originally intended but these control the state of the NINA-B1 module. Depending
on the current configuration, the
DSR
can be used to:
•
Enter command mode
•
Disconnect and/or toggle connectable status
•
Enable/disable the rest of the UART interface
•
Enter/wake up from the sleep mode
See the NINA-B1 series data sheet [2] for characteristic information about the UART interface.
