Pf sc diag

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definitions

  • SC/MC = PCB with both the state controller and motor controller processors.
  • SC = state controller, generic reference to the SC/MC
  • MC = motor controller, generic reference to the motor controller part of the PCB - or the whole motor controller process + power board
  • SM, STATEMACHINE : the primary statemachine that doesn't what were here for.
  • MC_SM, MOTOR (controller) statemachine, a state machine that runs on the motor controller that does impedance control, and handles overloads, etc.
  • ISP = in system programming - connectors / signals that are connected to ICD2 / Real-ice dsPIC programmer
  • FUP = field update port, Either of two 9 pin connectors on SC/MC board, uses ASYNC serial to communication without outside world. Also has pins for ISP
  • ISR = interrupt service routine


Root for the SC

ap_main.c:main() : starts off with initialization, and then becomes main loop (primary thread)

  • performs hardware and variable initialization, calling many sub functions for initialization
  • enables ISRs (which are defecto prioritizeable threads)
  1. At least two ISRs that operate the DMA that move data for the SPI and UARTs
  2. Tick timer ISR. Effectively sets a global that says tic. Don't believe does any actual work.
  • ultimately gets to the main loop of the code which is "while (1)"

This is the primary thread that does ALL the work. Although it appears to have only 2 functions : through nicely obfuscated coding, other functions get called.

At the next highest level we can say following actions are done in the main loop:

  • execute_cmd_rsp (see last page of ap_main.)
    • FUP = field update port, this is the ASYNC serial port interface to the outside world
    • difficult to explain as functions convoluted and are misnamed . However over all this code block deals with the MPD command / response protocol.
      • Gets 'messages' from buffers (either locally or from the FUP),
      • Routes /forwards messages to MC/IMU,
      • Processes message locally (command execution). MAJOR problem w/read real time clock, EEPROM
      • Passes back "answers" from the IMU/MC,
      • Answers requests to commands that we locally bound (executed)
        • Only the SC(both locally and via its FUP) can initiate messages that are executed on another processor (MC, IMU);
    • This block of code is the primary problem with the system.
      • We need to be able to send/route messages asynchronois to the STATEMACHINE (eg SM)
      • Thus the simple routing function needs to be in a thread at a HIGHER level than the SM , and we send messages asynchronous from the state controller, and we need to be