Compiling, Installing, and Configuring CPCd#

Downloading#

Download the daemon source files from Silicon Labs GitHub project:

https://github.com/SiliconLabs/cpc_daemon

The main branch contains the latest official versions. Early access versions are available in the specific version branches.

Compiling CPCd and the CPC Library#

The build essential and CMake packages in Linux are required for this step. Compile the CPC daemon in the source folder using the following commands:

mkdir build
cd build
cmake ../
make

Installing CPCd#

Super-user permissions are required to install the daemon, cpclib, and the configuration file. These can be installed with the following commands:

make install

The following components will be installed:

/usr/local/lib/libcpc.so.0.1
/usr/local/lib/libcpc.so.1
/usr/local/lib/libcpc.so
/usr/local/include/sl_enum.h
/usr/local/include/sl_cpc.h
/usr/local/bin/cpcd
/etc/cpcd.conf

Once installed, CPCd can be executed by invoking the cpcd command.

Configuring CPCd#

When running the daemon without arguments, it starts with the default configuration file installed in the previous step. To specify a different configuration file, use the --conf argument. For example:

cpcd --conf <configuration file path>

Obtaining the Version of CPCd#

If CPCd is started with the -v or --version argument, the daemon first prints the version of CPCd and exit. For example:

cpcd –version

Available Configurations#

CPCd is configured in a key/value manner in the cpcd.conf file.

Table: CPCd configuration


Description	Key	Possible Values	Default Value	Mandatory
Instance Name	INSTANCE_NAME	string	cpcd_0	No
Bus type selection	BUS_TYPE	UART SPI	UART	Yes
SPI device file	SPI_DEVICE_FILE	Any path to SPI device file	/dev/spidev0.0	Yes if BUS_TYPE is SPI
SPI Chip Select GPIO #	SPI_CS_GPIO	Any GPIO # (1)	24	Yes if BUS_TYPE is SPI
SPI RX IRQ GPIO	SPI_RX_IRQ_GPIO	Any GPIO # (1)	23	Yes if BUS_TYPE is SPI
SPI Bitrate	SPI_DEVICE_BITRATE	Any (2)	1000000	Yes if BUS_TYPE is SPI
SPI Mode	SPI_DEVICE_MODE	SPI_MODE_0 (3) SPI_MODE_1 SPI_MODE_2 SPI_MODE_3	SPI_MODE_0	Yes if BUS_TYPE is SPI
UART Device File	UART_DEVICE_FILE	Any (4)	/dev/serial0	Yes if BUS_TYPE is UART
UART Baud Rate	UART_DEVICE_BAUD	1200 (5) 2400 4800 19200 38400 57600 115200	115200	Yes if BUS_TYPE is UART
UART Hardware Flow Control	UART_HARDFLOW	True or false	False	Yes if BUS_TYPE is UART
Trace to stdout	STDOUT_TRACE	True or false	False	No
Trace to a file located under TRACES_FOLDER	TRACE_TO_FILE	True or False	False	No
Destination folder when TRACE_TO_FILE is enabled	TRACES_FOLDER	Any path that the CPCd can access	./cpcd-traces	No
The maximum number of open file descriptors.	RLIMIT_NOFILE	Depends on the OS limit	2000	No
Disable the encryption over CPC endpoints	DISABLE_ENCRYPTION	True or false	False	No

(1) Make sure the CPC daemon has enough permissions to access this GPIO.

(2) This setting depends on various factors. The bitrate needs to satisfy both side requirements.

(3) Refer to section 2.6 for additional details.

(4) This setting depends on the Linux SOC.

(5) These baud rates are typical, but any value that meets both requirements can be used.

Available SPI Modes#

The SPI_DEVICE_MODE configuration allows SPI clock polarity and phase to be configured, as shown in the following table.

Table: SPI Mode configuration


Mode	Clock Polarity (CPOL)	Clock Phase (CPHA)
SPI_MODE_0	0	0
SPI_MODE_1	0	1
SPI_MODE_2	1	0
SPI_MODE_3	1	1