18F4431 PWM question

[Tobias]

I am using a function generator for the input on this board. Based on the PWM, the 4431 will change its PWM channels too. The input signal is 100 hz. There is a 'pause' in the output side on PWM1,3,5,7. I am assuming I have something set up wrong and its not a hardware problem. I have tried this on four 4431's. The PWM will be fine then go high for an amount of time then go back to pulsing. If I am at 50% duty cycle the pause is the smallest. 20 and 80% is the worst. My function generator won't go lower or higher.

define CODE_SIZE 32
define osc 20
Include "modedefs.bas"	' Mode definitions for Serout
Include "Elapsed-18.bas"
OnOff1         var     PortE.1             'Input Signal from GPS to activate/deactivate row
OnOff2         var     PortE.0             'Input Signal from GPS to activate/deactivate row  
OnOff3         var     PortA.5             'Input Signal from GPS to activate/deactivate row
OnOff4         var     PortB.5             'Input Signal from GPS to activate/deactivate row                                         

Switch1        var     PortD.0             ''Output to 4066; activates Speed1
Switch2        var     PortE.2             ''Output to 4066; activates Speed2
Switch3        var     PortC.0             ''Output to 4066; activates Speed3
Switch4        var     PortC.3             ''Output to 4066; activates Speed4

MotorSpeed     var     PortC.1             'Input from 4066
Population     var     PortC.2             'Input from GPS

Enable1        var     PortD.1             ''Output Turns on Motor1 driver
Enable2        var     PortD.2             ''Output Turns on Motor2 driver
Enable3        var     PortD.3             ''Output Turns on Motor3 driver
Enable4        var     PortD.4             ''Output Turns on Motor4 driver

SinglePair     var     PortD.7             'Input Determines code path 
Input1         var     PortB.0             'PWM0
Input2         var     PortB.1             'PWM1
Input3         var     PortB.2             'PWM2
Input4         var     PortB.3             'PWM3

LCD            var     PortD.5
Duty1          Var     Word
Duty2          Var     Word
Duty3          Var     Word
Duty4          Var     Word
BCD1           var     byte
BCD10          var     byte
Rate           var     word
DisplayTenths  var     word 
MotorCount     var     byte              'Tracks motorspeed input
Mod1           var     byte              'Offset tracker to correct motorspeed
Mod2           Var     Byte              'Offset tracker to correct motorspeed
Mod3           var     byte              'Offset tracker to correct motorspeed
Mod4           Var     byte              'Offset tracker to correct motorspeed
PosMin1        var     bit
PosMin2        var     bit
PosMin3        var     bit
PosMin4        var     bit
HighTime       var     word
LowTime        var     word
TotalTime      var     word
Freq           var     word
Prefix          con      $FE             ' needed before each command
LcdCls          CON      $51             ' clear LCD (use PAUSE 5 after)
LcdLine1        CON      $00             ' move cursor to line 1
LcdLine2        con      $40             ' move curson to line 2
LcdLine3        con      $14             ' move curson to line 3
lcdLine4        con      $54             ' move curson to line 4
LcdCol1         con      $00             ' move cursor to column 1
LcdCol2         con      $07             ' move cursor to column 7
Backlight       con      $53             ' Backlighting 1-8
CursorPS        con      $45             'Cursor Position
CursorOn        con      $47             'Cursof On
CursorOff       con      $48             'Cursor Off

INTCON = 0            'Interrupts off for now
INTCON2.7 = 1         'Pull Ups disabled
ADCON0 = 0            'A/D OFF
ANSEL0 = %00000000    'All analogue channels to digital
ANSEL1 = %00000000    'All analogue channels to digital
TRISA = %111111       'PortA to inputs
TRISB = %00010000     'PortB to outputs, except B5
TRISC = %00000110     'PortC, Switch3 and Switch4 outputs; Motorspeed and Population inputs
TRISD = %00000000     'PortD, Switch 1 output; Enable1-4
TRISE = %011 
PWMCON0=%01111111     'All odd PWMs enabled, all independent
SSPCON=%00000000      'Disables Serial Port
'DTCON = %00000101       ' ~500nS dead-time (for complementary outputs only)
PTCON0 = %00000010      ' 1:1 postscale, Fosc/4 1:1 prescale, free running mode
Freq=%11111111

PTPERL =0'Freq.LowByte              
PTPERH =1'Freq.HighByte            

PWMCON1 = 1             ' updates enabled, overrides sync w/timebase
PTCON1 = %11000000      ' PWM time base is ON, counts up  500hz
FLTCONFIG = %00000010   ' enable fault A, cycle-by-cycle mode

Serout2 LCD, 84, [Prefix,LcdCLS]
pause 5

           
Test: 
Gosub BCD

'Open Loop Motor Control
If BCD1 = 0 then
  'gosub RowControl                 
  HIGH Enable1
  HIGH Enable2
  HIGH Enable3
  HIGH Enable4
  pulsin Population, 0, Rate
  Duty1 = (Rate*10)/492      '10%    489
  Duty2 = (Rate*10)/492      '20%    977
  Duty3 = (Rate*10)/492      '50%    2461
  Duty4 = (Rate*10)/492      '80%    3924
  Duty1 = Duty1*10
  Duty2 = Duty2*10
  Duty3 = Duty3*10
  Duty4 = Duty4*10 
  PDC0L = Duty4.LowByte
  PDC0H = Duty4.HighByte
  PDC1L = Duty2.LowByte
  PDC1H = Duty2.HighByte
  PDC2L = Duty3.LowByte
  PDC2H = Duty3.HighByte
  PDC3L = Duty1.LowByte
  PDC3H = Duty1.HighByte
  DisplayTenths=Duty1-(Duty1/10*10)
  SEROUT2 LCD,84, [Prefix,CursorPS,0, "Rate ", #Rate, " ", "Duty ", #Duty1/10, ".", #DisplayTenths, "%"]
endif
gosub TEst
BCD:
BCD1=PORTA
BCD1=BCD1 & $0F
BCD1=BCD1^ $0F 

'BCD10=PORTC
'BCD10=BCD10 & $F0
'BCD10=BCD10^ $F0
'BCD10 = BCD10 >>4

BCD10=PORTC
BCD10=BCD10 & $0F
BCD10=BCD10^ $0F
return

[Tobias]

I am wondering if its more of a scope deal than code, lol. When I look at a long range of sample points I see a pause. If anyone sees anything wrong with the code I would appreciate any input.

[Bruce]

One immediate problem would be the gosub TEst after your IF block. Should be GOTO Test.