configBusSpeed - Set bit timing rate of CAN channel

Syntax

Description

configBusSpeed(canch, busspeed) sets the speed of the CAN channel in a direct form that uses baseline bit timing calculation factors.

configBusSpeed(canch, busspeed, sjw, tseg1, tseg2, numberofsamples) sets the speed of the CAN channel canch to busspeed using the specified bit timing calculation factors to control the timing in an advanced form.

Tips

• Unless you have specific timing requirements for your CAN connection, use the direct form of configBusSpeed. Also note that you can set the bus speed only when the CAN channel is offline. The channel must also have initialization access to the CAN device.

• Synchronize all nodes on the network for CAN to work successfully. However, over time, clocks on different nodes will get out of sync, and must resynchronize. SJW specifies the maximum width (in time) that you can add to tseg1 (in a slower transmitter), or subtract from tseg2 (in a faster transmitter) to regain synchronization during the receipt of a CAN message.

Input Arguments

canch	The CAN channel object that you want to set the bit timing rate for.
busspeed	The user-specified bit timing rate for the specified object.
sjw	The synchronization jump width. This value is the maximum value of time bit adjustments.
tseg1	The length of time at the start of the sample point within a bit time.
tseg2	The length of time at the end of the sample point within a bit time.
numberofsamples	The specified count of bit samples used.

Examples

To configure the bus speed using baseline bit timing calculation, type:

canch = canChannel('Vector','CANCaseXL 1',1)
configBusSpeed(canch,250000)

To specify the bit timing calculations, type:

canch = canChannel('Kvaser', 'USBcan Professional 1', 1)
configBusSpeed(channel, 500000, 1, 4, 3, 1)

See Also

canChannel

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