In SX Microcontrollers, SX/B Compiler and SX-Key Tool, robotworkshop wrote:

Doesn't seem verbose at all.  Actually it's a lot shorter than what i'm trying to use in the program i'm working on at the moment.  I'm going to go through and optimize mine a bit but want to get it working right first.  I'm having a problem with it and I think I just need to take a step back or have another set of eyes look over the main routine.  It is for an SX48 acting as a co-processor for my robot project.  The ISR in the background is handing the reception of the serial commands which it buffers using your serial code.  It also keeps track of an encoder for the motor.

What i'm trying to do which is a bit different from your code above is to check to see if any serial data has been received.  If some has come in then it will deal with it and then go on to do some other processing before going back to the main loop again.  If no data has been received then it goes ahead and does it's processing and loops back to main to check for serial data and so on.  If this works out the way I hope it may be a useful technique to incorporate into other SX/B programs.  Any suggestions for the code below?

The weird part is that it doesn't seem to fall through and do the regular processing unless I keep sending some data to it.  It's almost as if my check to see if any characters are in the Serial receive buffer isn't working right.  Besides that all the other routines seem to work ok.  If I uncomment the first couple lines in the main routine it just displays the serial data on a set of 8 leds as a test.  That part works perfect now.  I had problems with that which were caused by extra Timer Interrupts but that was fixed by masking them off at the beginning of the program.  Below is a section of the code where the main loop is:



' Enable ISR to start accepting serial data
  active = True          ' Serial RX disabled until this flag is True
  HdBsy = False		' Tell Host we're ready for action!
  actmov = False       '  We're not in an active movement.

Main:

'Leds=RX_BYTE
'GOTO Main

  IF rxBufCnt = 0 THEN
    GOTO Motor_Control
  ENDIF


' cmdChar should be non-zero for a mutli-byte command
  IF cmdChar = 0 THEN
    char = RX_BYTE
    IF char = "C" THEN		' 67
      GOSUB CLR_FLAGS
      GOTO Motor_Control
    ENDIF
    IF char = "G" THEN		' 71
      GOSUB GO_TARGET      ' Goto position encTarget
      GOTO Motor_Control
    ENDIF
    IF char = "H" THEN		' 72
      GOSUB HOME_HEAD      ' Set encTarget to 0 then set actmov = True
      GOTO Motor_Control
    ENDIF
    IF char = "I" THEN		' 73
      GOSUB INIT_HEAD       ' Initialize head to point forward and set encValue & encTarget to 0
      GOTO Motor_Control
    ENDIF
    IF char = "F" THEN		' 70
      cmdChar = char           ' Set LEDs near wheels
      GOTO Motor_Control
    ENDIF
    IF char = "L" THEN		' 76
      cmdChar = char           ' Set LED's on front (8 LEDs)
      GOTO Motor_Control
    ENDIF
    IF char = "S" THEN		' 83
      cmdChar = char           ' Set new encTarget postion
      GOTO Motor_Control
    ENDIF

' We must have received a junk command.  Just flash the LEDs for now.
    GOSUB COMM_ERR

  ELSE
    IF rxBufCnt > 0 THEN
      IF char = "F" THEN	' 70
        GOSUB FOOT_LEDS
        cmdChar = 0
        GOTO Motor_Control
      ENDIF
      IF char = "L" THEN	' 76
        GOSUB Chest_Leds
        cmdChar = 0
        GOTO Motor_Control
      ENDIF
    ENDIF

    IF rxBufCnt > 1 THEN
      char = RX_CHKBYTE
      IF char = "S" THEN		' 83
        GOSUB Set_Target
        cmdChar = 0
        GOTO Motor_Control
      ENDIF
    ENDIF
  ENDIF

Motor_Control:

IF actmov = True THEN

' Check encoder & remaining distance.
'  Reached position?  If so, stop movement and reset flag
  encOffset = encTarget - encValue
  IF encOffset.15 = True THEN
    encOffset = -encOffset	' Use 2's complement to get ABS value
  ENDIF

  IF encOffset < 2 THEN
    actmov = False
    TIMER1 TIMER
    LOW Spd1
    HdBsy = False
  ELSE

' We're should be moving so adjust and update pwm
    encOffset = encTarget - encValue
    IF encOffset.15 = True THEN
      Dir1 = 1	' If the difference is negative we should move left
      encOffset = -encOffset	' Use 2's complement to get ABS value
    ELSE
      Dir1 = 0
    ENDIF

   ' Figure out how fast to move
    m1Spd = 750		' Slow

    IF encOffset > 50 THEN
      m1Spd = 925	' Medium
    ENDIF
    IF encOffset > 100 THEN
      m1Spd = 1110	' Fast
    ENDIF
    
    TIMER1 PWM, m1Spd, dutyCycle

  ENDIF

ENDIF

' check to see if head moved on it's own (or someone moved it)
' if more that allowable variance
'  setup new movement and set flag
'  if this has happened more than X then set head moved flag

'  IF encTarget = encValue THEN
'    GOTO Done
'  ENDIF
  encOffset = encTarget - encValue
  IF encOffset.15 = True THEN
    encOffset = -encOffset
  ENDIF
  IF encOffset > 10 THEN
    actmov = True
    HdBsy = True
  ENDIF

Done:
  GOTO Main	' Go back and do it all again.

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