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RTK65RX65Ndemo00_1

functionality: LED1 500 ms on, 500 ms off

  • LOCO clock 240 kHz
  • TMR1 source PCLKB, CMIA1: 240 + interrupt, vector INTB149 => 1kHz
  • INTB149 Millis-count, div 500 = toggle LED1 (PORTD bit 7) => 2 Hz

skipping smart configurator

  • in stead of selecting smart configurator, choose Finish >

taking functional code from RTK65RX65Ndemo00_0:

  • look at what start.S (assembly language) is doing. It can be read form left to reight, so mov #_data, r1 means move the number represented by _data to register r1.
  • Discover that, apart from assembly, it only calls 2 external routines by putting the address in register r7 and then performing jsr r7:
    1. HardwareSetup(), located in hwinit.c and without actual code.
    2. main(), located in the project names .c file, and also still empty.
  • Now by going back to project RTK65RX65Ndemo00_0 and stepping through the code with the debugger, in stead of pressing Run, one can discover what has to be done to initialize the controller.
  • I already have put the code in the .c file and changed the comment on top of the file to define the test setup and state the test date.
  • In order to ease searching for code I also put the interrupt vector code as protected code behind the main() function. On compilation with ^B the project will fail, as the interrupt vector is also defined in inthandler.c, so I had to change line 381 of that file to //void INT_Excep_PERIB_INTB149(void){ } to comment the vector there.
  • rename the file RKT5RX65Ndemo00_1.c to main.c

make the HardwareDebug settings:

  • Project > Properties >
  • Properties for RTK5RX65Ndemo00_1
    • Run/Debug Settings > RTK5RX65Ndemo00_1 HardwareDebug > Edit... >
  • Edit launch configuration properties
    • Debugger > Connection Settings >
      • Clock: HOCO
      • Connection with Target Board: change dropdown selection JTag to Fine
      • Power: change dropdown selection Yes to No
    • OK > Apply and Close >
  • Control-B to build the project, or: Project > Build Project >

Debug/Run:

  • ^B (build project), F11 (Debug), Confirm Perspective Switch Yes > F8 (Resume), F8
  • ^F2 will terminate the debug session

result:

  • 8 files in "generate" folder, of which 1 line was commented out,
  • 1 file in "src" folder has all code that matters for the developer
  • prog: 3272 (was 15648 with smart configurator)
  • constant: 1176 (was 1504)
  • data: 0 (was 12)
  • bss: 4 (was 2116)
  • other: 28 (was 5404)

note: If debugging and repeatedly choosing "Step Into" only 3 source files will open:

  1. start.S: startup code after reset in assembly language
  2. hwinit.c: containing the empty HardwareSetup() function
  3. main.c: containing the functional code

One can see that by looking into the hardware manual it is possible, with some more effort, to compact the code a lot and gain some insight in what is happening. I would advise you as a reader to take this project and single-step through its code while having the hardware manual alongside, just to understand why some code is there.

The next project will do clock switching to a default speed of 16 MHz, but use even less program memory for the same LED functionality, all without touching compiler optimization settings.