Channel¶
openChannel()¶
- canlib.canlib.openChannel(channel, flags=0, bitrate=None, data_bitrate=None)[source]¶
Open CAN channel
Retrieves a
Channel
object for the given CANlib channel number using the supplied flags.Example usage:
>>> bitrate = canlib.busparams.BusParamsTq( ... tq=40, ... phase1=5, ... phase2=6, ... sjw=4, ... prescaler=2, ... prop=28, ... ) >>> data_bitrate = canlib.busparams.BusParamsTq( ... tq=40, ... phase1=31, ... phase2=8, ... sjw=2, ... prescaler=2, ... ) >>> ch = canlib.openChannel( ... channel=0, ... flags=canlib.Open.CAN_FD, ... bitrate=bitrate, ... data_bitrate=data_bitrate, ... )
Note
If both
bitrate
anddata_bitrate
is given, both must be of the same type, i.e. either BusParamsTq or BITRATE flags. It is not supported to mix the two.- Parameters
channel (
int
) – CANlib channel numberflags (
int
) – Flags, a combination of thecanlib.canlib.Open
flag values. Default is zero, i.e. no flags.bitrate (
BusParamsTq
orBitrate
orBitrateFD
) – The desired bitrate. If the bitrate is not aBusParamsTq
, the predefinedBitrate
values are used for classic CAN andBitrateFD
values are used for CAN FD, e.g.canlib.Bitrate.BITRATE_1M
andcanlib.BitrateFD.BITRATE_1M_80P
. For CAN FD, this parameter gives the arbitration bitrate.data_bitrate (
BusParamsTq
orBitrateFD
) – The desired data bitrate for CAN FD. If notBusParamsTq
is given, the predefinedBitrateFD
values are used, e.g.canlib.BitrateFD.BITRATE_500K_80p
. This parameter is only used when opening a CAN FD channel.
- Returns
A
Channel
object created with channel and flags
New in version 1.6: The bitrate and data_bitrate arguments was added.
Changed in version 1.16: The bitrate and data_bitrate arguments now accept
BusParamsTq
objects.
ErrorCounters¶
- class canlib.canlib.channel.ErrorCounters(tx, rx, overrun)¶
Error counters returned by
Channel.read_error_counters
.- property overrun¶
Alias for field number 2
- property rx¶
Alias for field number 1
- property tx¶
Alias for field number 0
Channel¶
- class canlib.canlib.Channel(channel_number, flags=0)[source]¶
Helper class that represents a CANlib channel.
This class wraps the canlib class and tries to implement a more Pythonic interface to CANlib.
Channels are automatically closed on garbage collection, and can also be used as context managers in which case they close as soon as the context exits.
- announceIdentityEx(item, value)[source]¶
AnnounceIdentityEx function is used by certain OEM applications.
New in version 1.17.
- bitrate_to_BusParamsTq(freq_a, freq_d=None)[source]¶
Calculate bus parameters based on predefined frequencies.
This function uses the
Bitrate
andBitrateFD
values to create bus parameters for use with the new bus parameter API.- Parameters
- Returns
(
nominal
,None
) for classic CAN, wherenominal
is aBusParamsTq
object.(
nominal
,data
) for CAN FD, where bothnominal
anddata
areBusParamsTq
objects, representing the arbitration bitrate and the data bitrate, respectively.
New in version 1.17.
- busOff()[source]¶
Takes the specified channel off-bus.
Closes the channel associated with the handle. If no other threads are using the CAN circuit, it is taken off bus. The handle can not be used for further references to the channel.
- busOn()[source]¶
Takes the specified channel on-bus.
If you are using multiple handles to the same physical channel, for example if you are implementing a multithreaded application, you must call busOn() once for each handle.
- canAccept(envelope, flag)[source]¶
Set acceptance filters mask or code.
This routine sets the message acceptance filters on a CAN channel.
Setting flag to
AcceptFilterFlag.NULL_MASK
(0) removes the filter.Note that not all CAN boards support different masks for standard and extended CAN identifiers.
- Parameters
envelope – The mask or code to set.
flag – Any of
AcceptFilterFlag
- canSetAcceptanceFilter(code, mask, is_extended=False)[source]¶
Set message acceptance filter.
This routine sets the message acceptance filters on a CAN channel. The message is accepted
if id AND mask == code
(this is actually imlepemented asif ((code XOR id) AND mask) == 0
).Using standard 11-bit CAN identifiers and setting
mask = 0x7f0,
code = 0x080
accepts CAN messages with standard id 0x080 to 0x08f.
Setting the mask to canFILTER_NULL_MASK (0) removes the filter.
Note that not all CAN boards support different masks for standard and extended CAN identifiers.
- Parameters
mask (
int
) – A bit mask that indicates relevant bits with ‘1’.code (
int
) – The expected state of the masked bits.is_extended (
bool
) – IfTrue
, both mask and code applies to 29-bit CAN identifiers.
- property channel_data¶
canGetHandleData
helper object for this channelSee the documentation for
ChannelData
/HandleData
for how it can be used to perform all functionality of the C functioncanGetHandleData
.New in version 1.13.
- Type
HandleData
- close()[source]¶
Close CANlib channel
Closes the channel associated with the handle. If no other threads are using the CAN circuit, it is taken off bus.
Note
It is normally not necessary to call this function directly, as the internal handle is automatically closed when the
Channel
object is garbage collected.
- device()[source]¶
Get a Device object from the current channel
- Returns
Device
– Device used by this channel,
New in version 1.16.
- fileCopyFromDevice(deviceFileName, hostFileName=None)[source]¶
Copy an arbitrary file from the device to the host.
- Parameters
deviceFileName (
str
) – The device file name.hostFileName (
str
, optional) – The target host file name. Defaults to deviceFileName.
- fileCopyToDevice(hostFileName, deviceFileName=None)[source]¶
Copy an arbitrary file from the host to the () isdevice.
The filename must adhere to the FAT ‘8.3’ naming standard, max 8 characters - a dot - max 3 characters.
- Parameters
hostFileName (
str
) – The target host file name.deviceFileName (
str
, optional) – The device file name. Defaults to the same as hostFileName.
- fileDiskFormat()[source]¶
Format the disk on the device, not supported by all devices.
New in version 1.11.
- fileGetName(fileNo)[source]¶
Get the name of the file with the supplied number.
- Parameters
fileNo (
int
) – The number of the file.- Returns
str
– The name of the file.
- flashLeds(action, timeout_ms)[source]¶
Turn Leds on or off.
- Parameters
action (
int
) – One ofcanlib.canlib.LEDAction
, defining which LED to turn on or off.timeout_ms (
int
) – Specifies the time, in milliseconds, during which the action is to be carried out. When the timeout expires, the LED(s) will return to its ordinary function.
- getBusOutputControl()[source]¶
Get driver type
This function retrieves the current CAN controller driver type. This corresponds loosely to the bus output control register in the CAN controller, hence the name of this function.
Note
Not all CAN driver types are supported on all cards.
- Returns
drivertype (
canlib.Driver
) – Driver type to set.
New in version 1.11.
- getBusParams()[source]¶
Get bus timing parameters for classic CAN.
This function retrieves the current bus parameters for the specified channel.
- Returns: A tuple containing:
freq: Bitrate in bit/s.
tseg1: Number of quanta from but not including the Sync Segment to the sampling point.
tseg2: Number of quanta from the sampling point to the end of the bit.
sjw: The Synchronization Jump Width, can be 1,2,3, or 4.
noSamp: The number of sampling points, only 1 is supported.
syncmode: Unsupported, always read as zero.
- getBusParamsFd()[source]¶
Get bus timing parameters for BRS in CAN FD.
This function retrieves the bus current timing parameters used in BRS (Bit rate switch) mode for the current CANlib channel.
The library provides default values for tseg1_brs, tseg2_brs and sjw_brs when freq is a
BitrateFD
value.If freq is any other value, no default values are supplied by the library.
For finding out whether a channel is opened using
CAN_FD
orCAN_FD_NONISO
flags, seeis_can_fd()
- Returns: A tuple containing:
freq_brs: Bitrate in bit/s.
tseg1_brs: Number of quanta from (but not including) the Sync Segment to the sampling point.
tseg2_brs: Number of quanta from the sampling point to the end of the bit.
sjw_brs: The Synchronization Jump Width.
- getChannelData_CardNumber()[source]¶
Deprecated function
Deprecated since version 1.5: Use
ChannelData
;ChannelData(Channel.index).card_number
- getChannelData_Chan_No_On_Card()[source]¶
Deprecated function
Deprecated since version 1.5: Use
ChannelData
;ChannelData(Channel.index).chan_no_on_card
- getChannelData_Cust_Name()[source]¶
Deprecated function
Deprecated since version 1.5: Use
ChannelData
;ChannelData(Channel.index).custom_name
- getChannelData_DriverName()[source]¶
Deprecated function
Deprecated since version 1.5: Use
ChannelData
;ChannelData(Channel.index).driver_name
- getChannelData_EAN()[source]¶
Deprecated function
Deprecated since version 1.5: Use
ChannelData
;ChannelData(Channel.index).card_upc_no
- getChannelData_Firmware()[source]¶
Deprecated function
Deprecated since version 1.5: Use
ChannelData
;ChannelData(Channel.index).card_firmware_rev
- getChannelData_Name()[source]¶
Deprecated function
Deprecated since version 1.5: Use
ChannelData
;ChannelData(Channel.index).device_name
- getChannelData_Serial()[source]¶
Deprecated function
Deprecated since version 1.5: Use
ChannelData
;ChannelData(Channel.index).card_serial_no
- get_bus_params_tq()[source]¶
Get bus timing parameters, in time quanta
This function retrieves the current bus parameters for the specified channel. Only the returned
nominal
parameter is valid when classic CAN is in use.Returns: A
tuple
containing:nominal: (
BusParamsTq
) Nominal bus timing parameters, also used in classic CAN.data: (
BusParamsTq
) Bus timing parameters for data rate in CAN FD.New in version 1.16.
- get_io_pin(index)[source]¶
Return I/O pin using index
- Returns
iopin.IoPin
– io pin object for index (Any ofiopin.AnalogIn
,iopin.DigitalOut
etc)
New in version 1.8.
- ioCtl_flush_rx_buffer()[source]¶
Deprecated function
Deprecated since version 1.5: Use
IOControl
;Channel.iocontrol.flush_rx_buffer()
.
- ioCtl_get_report_access_errors()[source]¶
Deprecated function
Deprecated since version 1.5: Use
IOControl
;Channel.iocontrol.report_access_errors
- ioCtl_set_report_access_errors(on=0)[source]¶
Deprecated function
Deprecated since version 1.5: Use
IOControl
;Channel.iocontrol.report_access_errors = on
- ioCtl_set_timer_scale(scale)[source]¶
Deprecated function
Deprecated since version 1.5: Use
IOControl
;Channel.iocontrol.timer_scale = scale
- io_confirm_config()[source]¶
Confirm current I/O configuration
It is required to confirm a configuration by calling this function before accessing any I/O pins value.
New in version 1.8.
- io_pins()[source]¶
Generator that returns all I/O pins one by one
Returns object depending on pin type and direction:
iopin.AnalogIn
,iopin.AnalogOut
,iopin.DigitalIn
,iopin.DigitalOut
oriopin.Relay
.New in version 1.8.
- property iocontrol¶
canIoCtl
helper object for this channelSee the documentation for
IOControl
for how it can be used to perform all functionality of the C functioncanIoCtl
.Example usage:
>>> from canlib import canlib >>> ch = canlib.openChannel(channel=0) >>> ch.iocontrol.timer_scale 1000 >>> ch.iocontrol.local_txecho = False
- Type
- is_can_fd()[source]¶
Return True if the channel has been opened with the
CAN_FD
orCAN_FD_NONISO
flags.- Returns
True if CAN FD, False otherwise.
- kvDeviceGetMode()[source]¶
Read the current device’s mode.
Note
The mode is device specific, which means that not all modes are implemented in all products.
- Returns
int
– One ofDeviceMode
, indicating which mode is in use.
- kvDeviceSetMode(mode)[source]¶
Set the current device’s mode.
Note
The mode is device specific, which means that not all modes are implemented in all products.
- Parameters
mode (
int
) – One ofcanlib.canlib.DeviceMode
, defining which mode to use.
- read(timeout=0)[source]¶
Read a CAN message and metadata.
Reads a message from the receive buffer. If no message is available, the function waits until a message arrives or a timeout occurs.
Note
If you are using the same channel via multiple handles, the default behaviour is that the different handles will “hear” each other just as if each handle referred to a channel of its own. If you open, say, channel 0 from thread A and thread B and then send a message from thread A, it will be “received” by thread B.
This behaviour can be changed by setting
local_txecho
toFalse
(usingcanlib.canlib.IOControl
):>>> from canlib import canlib >>> ch = canlib.openChannel(channel=0) >>> ch.iocontrol.local_txecho = False
- Parameters
timeout (
int
) – Timeout in milliseconds, -1 gives an infinite timeout.- Returns
- readSpecificSkip(id_)[source]¶
Read a message with specified identifier
Reads a message with a specified identifier from the receive buffer. Any preceding message not matching the specified identifier will be removed in the receive buffer. If no message with the specified identifier is available, the function returns immediately with an error code.
- Returns
- readStatus()[source]¶
Return status for the current channel
Returns the latest status reported by the hardware in a combination of the flags
Stat
(bus on/error passive + status etc).- Returns
- readSyncSpecific(id_, timeout=0)[source]¶
Wait until the receive queue contains a message with the specified id
- read_error_counters()[source]¶
Read the error counters of the CAN controller
Returns the latest known values of the error counters in the specified circuit. If the error counters change values precisely when
read_error_counters
is called, it may not be reflected in the returned result.Use
clear_error_counters
viaChannel.iocontrol
to clear the counters.- Returns (
ErrorCounters
)A named tuple containing: rx: Receive error counter
tx: Transmit error counter
overrun: Number of overrun errors.
New in version 1.11.
- Returns (
- requestChipStatus()[source]¶
Request chip status messages
Requests that the hardware report the chip status (bus on/error passive status etc.) to the driver. The chip status can later be retrieved using
canlib.Channel.readStatus
.Note
The
requestChipStatus
function is asynchronous, that is, it completes before the answer is returned from the hardware. The time between a call torequestChipStatus
and the point in time where the chip status is actually available via a call tocanlib.Channel.readStatus
is not defined. Thecanlib.Channel.readStatus
always returns the latest data reported by the hardware.
- scriptEnvvarClose(envHandle)[source]¶
Low level function to close an Envvar
This should normally not be used directly, instead opening and closing of an envvar is automatically done when accessing via the
EnvVar
class throughChannel.envvar
- scriptEnvvarGetFloat(envHandle)[source]¶
Low level function to read an Envvar of type float
This should normally not be used directly, instead set and get the value of an envvar using the
EnvVar
class throughChannel.envvar
- scriptEnvvarGetInt(envHandle)[source]¶
Low level function to read an Envvar of type int
This should normally not be used directly, instead set and get the value of an envvar using the
EnvVar
class throughChannel.envvar
- scriptEnvvarOpen(name)[source]¶
Low level function to open an Envvar
This should normally not be used directly, instead opening and closing of an envvar is automatically done when accessing via the
EnvVar
class throughChannel.envvar
- scriptEnvvarSetFloat(envHandle, value)[source]¶
Low level function to set an Envvar of type float
This should normally not be used directly, instead set and get the value of an envvar using the
EnvVar
class throughChannel.envvar
- scriptEnvvarSetInt(envHandle, value)[source]¶
Low level function to set an Envvar of type int
This should normally not be used directly, instead set and get the value of an envvar using the
EnvVar
class throughChannel.envvar
- scriptGetText()[source]¶
Read text from subscribed script slots
Text-subscriptions must first be set up with
Channel.scriptRequestText
.- Returns
- Raises
canlib.canlib.CanNoMsg – No more text is currently available.
New in version 1.7.
- scriptLoadFile(slot, filePathOnPC)[source]¶
Load compiled script file from host(PC)
Loads a compiled script file (.txe) stored on the host (PC) into a script slot on the device. The scripts default channel will be the same channel used when this Channel object was created.
- Parameters
slot (
int
) – slot containing the running script we want to stop.filePathOnPC (
str
) – Path to compiled script (.txe) to load.
- scriptLoadFileOnDevice(slot, localFile)[source]¶
Load compiled, locally stored, script file
Loads a compiled script file (.txe) stored locally on the device (SD card) into a script slot on the device. The scripts default channel will be the same channel used when this Channel object was created.
- Parameters
slot (
int
) – slot containing the running script we want to stop.localFile (
str
) – Name of compiled script (.txe) to load.
- scriptRequestText(slot, request=<ScriptRequest.SUBSCRIBE: 2>)[source]¶
Set up a printf subscription to a selected script slot
- Parameters
slot (
int
) – The script slot to subscribe/unsubscribe from.request (
canlib.canlib.ScriptRequest
) – Whether to subscribe or unsubscribe.
Text printed with
printf()
by a t-script that you are subscribed to is saved and can be retrieved withChannel.scriptGetText
.New in version 1.7.
- scriptSendEvent(slotNo=0, eventType=1, eventNo=97, data=0)[source]¶
Send specified event to specified t script
Send an event with given type, event number, and associated data to a script running in a specific slot.
- scriptStatus(slot)[source]¶
Retreives t program status for selected slot
- Parameters
slot (
int
) – Slot number to be queried- Returns
canlib.ScriptStatus
New in version 1.6.
- scriptStop(slot, mode=<ScriptStop.NORMAL: 0>)[source]¶
Stop script running in specified slot
- Parameters
slot (
int
) – slot containing the running script we want to stop.mode (
canlib.ScriptStop
) – Default mode iscanlib.ScriptStop.NORMAL
.
- script_envvar_get_data(envHandle, len, start=0)[source]¶
Low level function to read a slice of an Envvar of type char
This should normally not be used directly, instead set and get the value of an envvar using the
EnvVar
class throughChannel.envvar
New in version 1.10.
- script_envvar_set_data(envHandle, value, len, start=0)[source]¶
Low level function to write a slice of an Envvar of type char
This should normally not be used directly, instead set and get the value of an envvar using the
EnvVar
class throughChannel.envvar
value
needs to be a bytes-like object or listNew in version 1.10.
- setBusOutputControl(drivertype=<Driver.NORMAL: 4>)[source]¶
Set driver type
This function sets the driver type for a CAN controller to e.g. silent mode. This corresponds loosely to the bus output control register in the CAN controller, hence the name of this function.
Note
Not all CAN driver types are supported on all cards.
- Parameters
drivertype (
canlib.Driver
) – Driver type to set.
- setBusParams(freq, tseg1=0, tseg2=0, sjw=0, noSamp=0, syncmode=0)[source]¶
Set bus timing parameters for classic CAN
This function sets the bus timing parameters for the specified CAN controller.
The library provides default values for tseg1, tseg2, sjw and noSamp when freq is a
Bitrate
, e.g.canlib.Bitrate.BITRATE_1M
, or aBitrateFD
value, e.g.canlib.BitrateFD.BITRATE_1M_80P
.If freq is any other value, no default values are supplied by the library.
If you are using multiple handles to the same physical channel, for example if you are implementing a multithreaded application, you must call busOff() once for each handle. The same applies to busOn() - the physical channel will not go off bus until the last handle to the channel goes off bus.
- Parameters
freq – Bitrate in bit/s.
tseg1 – Number of quanta from (but not including) the Sync Segment to the sampling point.
tseg2 – Number of quanta from the sampling point to the end of the bit.
sjw – The Synchronization Jump Width, can be 1,2,3, or 4.
nosamp – The number of sampling points, only 1 is supported.
syncMode – Unsupported and ignored.
Changed in version 1.17: Now accepts
canlib.canlib.Bitrate
andcanlib.canlib.BitrateFD
enumerations.
- setBusParamsFd(freq_brs, tseg1_brs=0, tseg2_brs=0, sjw_brs=0)[source]¶
Set bus timing parameters for BRS in CAN FD
This function sets the bus timing parameters used in BRS (Bit rate switch) mode for the current CANlib channel.
The library provides default values for tseg1_brs, tseg2_brs and sjw_brs when freq is a
BitrateFD
value, e.g.canlib.BitrateFD.BITRATE_1M_80P
.If freq is any other value, no default values are supplied by the library.
For finding out whether a channel is opened using
CAN_FD
orCAN_FD_NONISO
flags, seeis_can_fd
- Parameters
freq_brs – Bitrate in bit/s.
tseg1_brs – Number of quanta from (but not including) the Sync Segment to the sampling point.
tseg2_brs – Number of quanta from the sampling point to the end of the bit.
sjw_brs – The Synchronization Jump Width.
Changed in version 1.17: Now accepts
canlib.canlib.BitrateFD
enumerations.
- set_bus_params_tq(nominal, data=None)[source]¶
Set bus timing parameters, using time quanta
This function sets the bus timing parameters for the specified CAN controller. When setting bus parameters for CAN FD, both
nominal
anddata
must be given.If you are using multiple handles to the same physical channel, for example if you are implementing a multithreaded application, you must call
busOff()
once for each handle. The physical channel will not go off bus until the last handle to the channel goes off bus. The same applies tobusOn()
.- Parameters
nominal (
BusParamsTq
) – Nominal Bus timing parameters, also used for classic CANdata (
BusParamsTq
) – Bus timing parameters for data rate in CAN FD.
New in version 1.16.
- set_callback(function, event, context=None)[source]¶
Register callback function
This will register a callback function which is called when certain events occur. You can register at most one callback function per handle at any time.
Note:
The callback function is called in the context of a high-priority thread created by CANlib. You should take precaution not to do any time consuming tasks in the callback.
Small example of usage:
# Declare callback function def callback_func(hnd, context, event): event = canlib.Notify(event) # The nonlocal statement causes the listed identifiers to refer # to previously bound variables in the nearest enclosing scope # excluding globals. nonlocal callback_has_been_called print("Callback called, context:{}, event:{!r}".format(context, event)) # Notify the main program by setting the flag callback_has_been_called = True # setup communication variable and callback callback_has_been_called = False callback = canlib.dll.KVCALLBACK_T(callback_func) with canlib.openChannel(0) as ch: ch.set_callback(callback, context=121, event=canlib.Notify.BUSONOFF) # trigger the callback ch.busOn() # do something else time.sleep(0.5) # Verify that the callback was triggered assert callback_has_been_called
Note:
It is very important to make sure that you keep a reference to the callback type (
callback
in the sample above) for as long as any C library might call it. If it gets deleted by the garbage collector, calling it from C is likely to either cause a segfault or maybe even interpret random memory as machine language.- Parameters
function (
canlib.canlib.KVCALLBACK_T
) – A ctypes wrapped Python functionevent (
canlib.canlib.Notify
) – A combination of flags to indicate what events to trigger on
New in version 1.7.
- write(frame=None, *args, **kwargs)[source]¶
Send a CAN message.
This function sends a Frame object as a CAN message. Note that the message has been queued for transmission when this calls return. It has not necessarily been sent.
Note
If you are using the same channel via multiple handles, the default behaviour is that the different handles will “hear” each other just as if each handle referred to a channel of its own. If you open, say, channel 0 from thread A and thread B and then send a message from thread A, it will be “received” by thread B.
This behaviour can be changed by setting
local_txecho
toFalse
(usingcanlib.canlib.IOControl
):>>> from canlib import canlib >>> ch = canlib.openChannel(channel=0) >>> ch.iocontrol.local_txecho = False
Also see
Channel.write_raw
for sending messages without constructingcanlib.Frame
objects.Deprecated since version 1.5: Sending the
canlib.Frame
contents as separate arguments; this functionality has been taken over bywrite_raw
.- Parameters
frame (
canlib.Frame
)
- writeSync(timeout)[source]¶
Wait for queued messages to be sent
Waits until all CAN messages for the specified handle are sent, or the timeout period expires.
- Parameters
timeout (
int
) – The timeout in milliseconds,None
or0xFFFFFFFF
for an infinite timeout.
- writeWait(frame, timeout, *args, **kwargs)[source]¶
Sends a CAN message and waits for it to be sent.
This function sends a CAN message. It returns when the message is sent, or the timeout expires. This is a convenience function that combines write() and writeSync().
Deprecated since version 1.5: Sending the
Frame
contents as separate arguments; this functionality has been taken over bywriteWait_raw
.- Parameters
frame (
canlib.Frame
) – Frame containing the CAN data to be senttimeout (
int
) – The timeout, in milliseconds. 0xFFFFFFFF gives an infinite timeout.
- writeWait_raw(id_, msg, flag=0, dlc=0, timeout=0)[source]¶
Sends a CAN message and waits for it to be sent.
This function sends a CAN message. It returns when the message is sent, or the timeout expires. This is a convenience function that combines write() and writeSync().
- Parameters
id_ – The identifier of the CAN message to send.
msg – An array or bytearray of the message data
flag – A combination of
canlib.canlib.MessageFlag
. Use this parameter e.g. to send extended (29-bit) frames.dlc – The length of the message in bytes. For Classic CAN dlc can be at most 8, unless
canlib.canlib.Open.ACCEPT_LARGE_DLC
is used. For CAN FD dlc can be one of the following 0-8, 12, 16, 20, 24, 32, 48, 64. Optional, if omitted, dlc is calculated from the msg array.timeout – The timeout, in milliseconds. 0xFFFFFFFF gives an infinite timeout.
- write_raw(id_, msg, flag=0, dlc=None)[source]¶
Send a CAN message
See docstring of
Channel.write
for general information about sending CAN messages.The variable name id (as used by canlib) is a built-in function in Python, so the name
id_
is used instead.- Parameters
id_ – The identifier of the CAN message to send.
msg – An array or bytearray of the message data
flag – A combination of
canlib.canlib.MessageFlag
. Use this parameter e.g. to send extended (29-bit) frames.dlc – The length of the message in bytes. For Classic CAN dlc can be at most 8, unless
canlib.canlib.Open.ACCEPT_LARGE_DLC
is used. For CAN FD dlc can be one of the following 0-8, 12, 16, 20, 24, 32, 48, 64. Optional, if omitted, dlc is calculated from the msg array.
CanBusStatistics¶
- class canlib.canlib.structures.CanBusStatistics[source]¶
Result from reading bus statistics using
canlib.canlib.Channel.get_bus_statistics
.- Variables
busLoad (
int
) – The bus load, expressed as an integer in the interval 0 - 10000 representing 0.00% - 100.00% bus load.errFrame (
int
) – Number of error frames.extData (
int
) – Number of received extended (29-bit identifiers) data frames.extRemote (
int
) – Number of received extended (29-bit identifiers) remote frames.overruns (
int
) – The number of overruns detected by the hardware, firmware or driver.stdData (
int
) – Number of received standard (11-bit identifiers) data frames.stdRemote (
int
) – Number of received standard (11-bit identifiers) remote frames.