Thread: CAN reliability
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Unread 12-07-2010, 14:57
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Re: CAN reliability

Okay, so on to initialization. Here's a list of commands that would be logical to use when configuring a Jaguar for position control. (I'm choosing position control because it has the most things to configure)
  1. Firmware version (0 bytes data)
  2. Position Mode Enable (0 bytes data)
  3. Position reference (0 bytes data)
  4. Proportional Constant (4 bytes data)
  5. Integral Constant (4 bytes data)
  6. Derivative Constant (4 bytes data)
  7. Encoder lines or Potentiometer turns (4 bytes data)
  8. Break/Coast (1 byte data)
  9. Soft limit switches (1 byte data)
  10. Forward soft limit (5 bytes data)
  11. Reverse soft limit (5 bytes data)
  12. Position Set (4 bytes data)
The sum of data bytes being sent here is 32 bytes, though it is being sent over 12 messages.
If the whole CAN message is sent through RS232, that should be (14*(8+3)+32)bytes / 11,520 bytes/s or 16ms to initialize a Jaguar for position mode.

If only the arbitration field and the data is sent, it should be (14*(4+3)+32)bytes / 11,520 bytes/s or 9ms to initialize a Jaguar for position mode.

So, now that I have some theoretical calculations to compare it to, I shall make some tests.
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