Where is the CAN LIN bus analyzer available, it is better to be specific

If you want to set up the CAN bus, there are 5 main steps:

First: set all kinds of parameters.

Second: Allocate the probability of triggering an event.

Third: Delete the unwanted CAN information from the filter.

Fourth: Reload the corresponding information in the CAN bus database.

Sixth: Start exporting the information and save it in the format you want.

The oscilloscope also has a CAN LIN bus analysis function, and the setup is similar, using LIN as an example.

Since the LIN bus is generally around 12V maximum, the oscilloscope's vertical gear can be set to 2V div, and the time base can be set to about 500 s. Then open the oscilloscope's decode menu, configure the LIN bus, and select the baud rate that matches the signal under test. Adjust the bus threshold level to the waveform display range and you can see the decoded data.

You can change the trigger mode to bus decoding trigger, and set the appropriate frame ID to stabilize the waveform.

The figure below shows the LIN bus control signal of the wiper motor of Audi cars.

The LIN bus waveform is a square wave, which represents the binary state in a serial data stream. The waveform seen should be free of noticeable distortion and noise glitches. Decoded packets display the real-time data content of the bus activity in hexadecimal format.

The "Frame ID" is displayed in yellow, which is 23 in the image above, the "Data" display color is white, the "Checksum" display color is green, and if the checksum is incorrect, it is displayed in red "E".

If no information is sent to the LIN data bus (bus idle) or if there is a recessive bit sent to the LIN data bus, the maximum value on the LIN bus signal is the implicit level.

When transmitting dominant bits, the transceiver within the transmit control unit connects the LIN data bus to ground. This is expressed as the minimum value on the LIN bus signal, i.e., the dominant level.

The message format of the LIN bus consists of two parts: the initial message (message header) and the reply (response message content).

The initial message (message header) is sent periodically by the LIN main control unit, and consists of a synchronization pause area, a synchronization demarcation area, a synchronization area, and an identification area. Reply (reply to message content), sent by or from the LIN master control unit.

1.Signal lines and widths and signals.

The CAN bus works with two signal lines (twisted pair) of CAN HIGH and CAN 1 calendar W, and the level of the two lines of the comfortable CAN bus is about OV and 5V (when recessive) respectively.

The LIN bus only works with a signal line equivalent to CAN, and the level is close to the battery voltage when it is hidden, and fluctuates accordingly; When dominant, the level is close to the ground level. Use 0·35mmz wire, the color is white wire on a purple background.

2. Components. When the CAN bus works, in addition to the relatively complex transceiver, a special protocol controller is usually required in the electronic unit. The transceiver in the LIN bus unit is simpler, and due to the simplicity of the protocol, there is usually no need for a protocol controller that is specifically guarded.

3. Transmission rate.

CAN buses have a high bit rate, typically 5 ookb s when used in automobiles, and the lowest is 1 ookb s. The highest bit rate for the LIN bus is 2Okbs, typically using a rate of 1920ob s or 9600b s.

4. System structure.

CAN bus is a multi-host system, that is, any electronic unit of the receiving bus can obtain bus control through bus arbitration, and send information to the bus system, and the unit is the host when sending out a complete ID. CAN buses use 11-bit IDs (or even more) and can have more units in a subsystem.

The LIN bus is a single-master multi-slave system, each subsystem has and only one master, all information transmission is controlled by the master, and the slave must wait for the master to send out the ID corresponding to it before sending information. The LIN bus uses a 6-bit ID and can only have fewer units in a subsystem.

5. Reliability.

The CAN bus uses a highly reliable CRC calibration.

The LIN bus uses a relatively unreliable sum check with carry.

6. Cost. CAN bus can be used for various information transmission occasions, but the cost is high and the manufacturability is relatively poor.

LIN buses can only be used in situations where the speed and reliability requirements are not very high, such as comfort systems or some subsystems, etc., with the advantage of low cost and good manufacturability.