Please explain LIN Parameter, bit quantization.
We are using number of Local Interconnect Network(LIN) channels from Renesas RH850 / U2A16 Microcontroller in our embedded system. All LIN channels in our embedded system are Master.
What is LIN Parameter called bit quantization? I didn't easily find explanation of this parameter in LIN Controller user's manual.
What is LIN Parameter called bit quantization? I didn't easily find explanation of this parameter in LIN Controller user's manual.
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>> All LIN channels in our embedded system are Master.
How many are there? Does every uC run at the same clock speed? Does every channel run at the same baud rate?
What sort of traffic are the channels handling? Are you planning or willing to synch channels before every message?
All the essential variables for the LIN will be in the header file. Maybe you will only have to specify clock speed and baud rate. But those two parameters will set the bit quantization.
I looks like Sec 2.4 is all about calculating the clock accuracy required for system components.
If you have a stable clock for every chip, and conservative baud rates for all channels, then you may not have to worry about clock drift.
If you are trying to push data as fast as you can, you will need to worry about clock drift, packet sizes, periodic resynching, and error handling.
How many are there? Does every uC run at the same clock speed? Does every channel run at the same baud rate?
What sort of traffic are the channels handling? Are you planning or willing to synch channels before every message?
All the essential variables for the LIN will be in the header file. Maybe you will only have to specify clock speed and baud rate. But those two parameters will set the bit quantization.
I looks like Sec 2.4 is all about calculating the clock accuracy required for system components.
If you have a stable clock for every chip, and conservative baud rates for all channels, then you may not have to worry about clock drift.
If you are trying to push data as fast as you can, you will need to worry about clock drift, packet sizes, periodic resynching, and error handling.
ASKER
>> How many are there?
We have Two microcontrollers on our embedded board. Four LIN channels on Microcontroller A and Four LIN channels on Microcontroller B.
>> Does every uC run at the same clock speed?
Yes
>> Does every channel run at the same baud rate?
Yes
>> What sort of traffic are the channels handling?
I am not on the driver team. I am not sure how application software is using LIN. Some sensor data is send on LIN channels. The application is ADAS vehicle.
>> Are you willing to synch channels before every message?
I believe Sync Break and Sync Byte are used to sync channels. Is further synchronization needed? If yes, I'm not aware how to achieve it.
>> All the essential variables for the LIN will be in the header file.
I didn't write the LIN driver. Therefore, I don't know the answer to this question but I can read the code to find the answer to this question.
>> Maybe you only have to specify clock speed and baud rate. But those two parameters will set the bit quantization.
I believe this answered my question. We have only specified clock speed and baud rate. Ok. these two parameters must be setting the bit quantization.
We have Two microcontrollers on our embedded board. Four LIN channels on Microcontroller A and Four LIN channels on Microcontroller B.
>> Does every uC run at the same clock speed?
Yes
>> Does every channel run at the same baud rate?
Yes
>> What sort of traffic are the channels handling?
I am not on the driver team. I am not sure how application software is using LIN. Some sensor data is send on LIN channels. The application is ADAS vehicle.
>> Are you willing to synch channels before every message?
I believe Sync Break and Sync Byte are used to sync channels. Is further synchronization needed? If yes, I'm not aware how to achieve it.
>> All the essential variables for the LIN will be in the header file.
I didn't write the LIN driver. Therefore, I don't know the answer to this question but I can read the code to find the answer to this question.
>> Maybe you only have to specify clock speed and baud rate. But those two parameters will set the bit quantization.
I believe this answered my question. We have only specified clock speed and baud rate. Ok. these two parameters must be setting the bit quantization.
ASKER
1. Number of bits of the SYNC field used to count for the bit rate, Nsync
2. Number of segments (quanta) within a bit to set the resolution of the sampling point, Nspb
3. Amount of division factor by the bit rate pre-scaler, Nbrp
Are these parameters programmed in the LIN Controller driver?