
3.6.6 Pulse Counter (PCNT)
The Pulse Counter (PCNT) peripheral can be used for counting pulses on a single input or to decode quadrature encoded inputs. The
clock for PCNT is selectable from either an external source on pin PCTNn_S0IN or from an internal timing reference, selectable from
among any of the internal oscillators, except the AUXHFRCO. The peripheral may operate in energy mode EM0 Active, EM1 Sleep,
EM2 Deep Sleep, and EM3 Stop.
3.6.7 Watchdog Timer (WDOG)
The watchdog timer can act both as an independent watchdog or as a watchdog synchronous with the CPU clock. It has windowed
monitoring capabilities, and can generate a reset or different interrupts depending on the failure mode of the system. The watchdog can
also monitor autonomous systems driven by PRS.
3.7 Communications and Other Digital Peripherals
3.7.1 Universal Synchronous/Asynchronous Receiver/Transmitter (USART)
The Universal Synchronous/Asynchronous Receiver/Transmitter is a flexible serial I/O interface. It supports full duplex asynchronous
UART communication with hardware flow control as well as RS-485, SPI, MicroWire and 3-wire. It can also interface with devices sup-
porting:
• ISO7816 SmartCards
• IrDA
• I
2
S
3.7.2 Low Energy Universal Asynchronous Receiver/Transmitter (LEUART)
The unique LEUART
TM
provides two-way UART communication on a strict power budget. Only a 32.768 kHz clock is needed to allow
UART communication up to 9600 baud. The LEUART includes all necessary hardware to make asynchronous serial communication
possible with a minimum of software intervention and energy consumption.
3.7.3 Inter-Integrated Circuit Interface (I
2
C)
The I
2
C interface enables communication between the MCU and a serial I
2
C bus. It is capable of acting as both a master and a slave
and supports multi-master buses. Standard-mode, fast-mode and fast-mode plus speeds are supported, allowing transmission rates
from 10 kbit/s up to 1 Mbit/s. Slave arbitration and timeouts are also available, allowing implementation of an SMBus-compliant system.
The interface provided to software by the I
2
C peripheral allows precise timing control of the transmission process and highly automated
transfers. Automatic recognition of slave addresses is provided in active and low energy modes.
3.7.4 Peripheral Reflex System (PRS)
The Peripheral Reflex System provides a communication network between different peripherals without software involvement. Peripher-
als producing Reflex signals are called producers. The PRS routes Reflex signals from producers to consumer peripherals, which in
turn perform actions in response. Edge triggers and other functionality such as simple logic operations (AND, OR, NOT) can be applied
by the PRS to the signals. The PRS allows peripheral to act autonomously without waking the MCU core, saving power.
3.7.5 Low Energy Sensor Interface (LESENSE)
The Low Energy Sensor Interface LESENSE
TM
is a highly configurable sensor interface with support for up to 16 individually configura-
ble sensors. By controlling the analog comparators, ADC, and DAC, LESENSE is capable of supporting a wide range of sensors and
measurement schemes, and can for instance measure LC sensors, resistive sensors and capacitive sensors. LESENSE also includes a
programmable finite state machine which enables simple processing of measurement results without CPU intervention. LESENSE is
available in energy mode EM2, in addition to EM0 and EM1, making it ideal for sensor monitoring in applications with a strict energy
budget.
3.8 Security Features
3.8.1 GPCRC (General Purpose Cyclic Redundancy Check)
The GPCRC block implements a Cyclic Redundancy Check (CRC) function. It supports both 32-bit and 16-bit polynomials. The suppor-
ted 32-bit polynomial is 0x04C11DB7 (IEEE 802.3), while the 16-bit polynomial can be programmed to any value, depending on the
needs of the application.
BGM13S Blue Gecko
Bluetooth
®
SiP Module Data Sheet
System Overview
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