NINA-B3 series - System integration manual
UBX-17056748 - R13
System description
Page 12 of 72
C1-Public
1.7.4
I
2
C interface
The Inter-Integrated Circuit (I2C) interfaces can be used to transfer or receive data on a 2-wire bus
network. NINA-B3 can operate as both Central and Peripheral on the I2C bus using both standard
(100 kbps) and fast (400 kbps) transmission speeds. The interface uses the
SCL
signal to clock
instructions and data on the
SDA
signal.
External pull-up resistors are required for the I2C interface. The value of the pull-up resistor should be
selected depending on the speed and capacitance of the bus. See Electrical specifications in the
NINA-B3 series data sheet
for recommended resistor values.
1.7.5
USB 2.0 interface
The NINA-B3 series modules include a full speed Universal Serial Bus (USB) device interface compliant
with version 2.0 of the USB specification. The pin configuration of the USB interface is provided below:
•
VBUS, 5 V supply input, required in order to use the interface
•
USB_DP, USB_DM, differential data pair
The USB interface has a dedicated power supply that requires a 5 V supply voltage for the
VBUS
pin.
This allows the USB interface to be used even though the rest of the module might be battery powered
or supplied by a 1.8 V supply, etc.
1.8
GPIO pins
In an un-configured state, NINA-B3 modules have 38 GPIO pins and no analog or digital interfaces. All
interfaces or functions must be allocated to a GPIO pin before use. Eight of the 38 GPIO pins are analog
enabled, meaning that they can have an analog function allocated to them. In addition to the serial
interfaces,
shows the digital and analog functions that can be assigned to a GPIO pin.
Function
Description
Default
NINA-B3 pin
Configurable
GPIOs
General purpose input
Digital input with configurable pull-up, pull-down, edge detection
and interrupt generation
Any
General purpose output
Digital output with configurable drive strength, push-pull, open
collector, or open emitter output
Any
Pin disabled
Pin is disconnected from the input and output buffers.
All*
Any
Timer/ counter
High precision time measurement between two pulses/ Pulse
counting with interrupt/event generation
Any
Interrupt/ Event trigger
Interrupt/event trigger to software application/ Wake-up event
Any
HIGH/LOW/Toggle on event Programmable digital level triggered by internal or external events
without CPU involvement
Any
ADC input
8/10/12/14-bit analog to digital converter
Any analog
Analog comparator input
Compare two voltages, capable of generating wake-up events and
interrupts
Any analog
PWM output
Output simple or complex pulse width modulation waveforms
Any
Connection status indicator Indicates if a BLE connection is maintained
BLUE**
Any
* = If left unconfigured
** = If using u-connectXpress software
Table 4: GPIO custom functions configuration
