Updating HPWM frequently, safe?

[mister_e]

try this

<font color="#000000">        <font color="#008000">'
        '       Pic Configuration
        '       =================
        </font>@ __CONFIG _INTRC_OSC_NOCLKOUT &amp; _WDT_ON &amp; _PWRTE_ON &amp; _MCLRE_OFF &amp; _BOD_ON         
        
        <font color="#008000">'
        '       Hardware configuration
        '       ======================
                '
                '       I/Os
                '       ----
        </font>TRISIO = %00010010        
                <font color="#008000">'
                '       ADC's
                '       -----
        </font>ANSEL = %00000010  
        <font color="#000080">DEFINE </font>ADC_BITS 10     <font color="#008000">' ADCIN resolution  (Bits)
        </font><font color="#000080">DEFINE </font>ADC_CLOCK 1     <font color="#008000">' ADC clock source  (Fosc/8)
        </font><font color="#000080">DEFINE </font>ADC_SAMPLEUS 11 <font color="#008000">' ADC sampling time (uSec)                      
        </font>ADCON0.7 = 1           <font color="#008000">' Right justified results
     
                '
                '       Comparator
                '       ----------
        </font>CMCON0 = 7             <font color="#008000">' Disable comparator
        </font>VRCON = 0              <font color="#008000">' CVreff = OFF
                '
                '       CCP
                '       ---
                        '   PWM Freq=4KHz
                        '   Initial duty cycle set to 50%
                        '   PICMultiCalc says
                        '   10 Bit resolution when prescaler = 1:1
                        '   MAX duty value 1000
                        '   PR2 = 249
        </font>CCP1CON = %00001100     <font color="#008000">' PWM mode
        </font>PR2 = 249               <font color="#008000">'         
        </font>T2CON = %00000100       <font color="#008000">' Start Timer2, Prescaller 1:1
      
        '   
        '       Software variables
        '       ==================
        </font>Duty    <font color="#000080">VAR WORD
        
        </font><font color="#008000">'
        '       Software constants
        '       ==================
        </font>PWM_ON  <font color="#000080">CON </font>%00001100
        PWM_OFF <font color="#000080">CON </font>0
        
        <font color="#008000">'
        '       Software/Hardware initialisation
        '       ================================
        </font>GPIO = 0
        <font color="#000080">PAUSE </font>50    <font color="#008000">' OSC settle delay
        </font>Duty = 0
        <font color="#000080">GOSUB </font>SetPWMDuty
        
        <font color="#008000">'------------------------------&lt; Main program &gt;-----------------------------------
        '
</font>Start:
        <font color="#000080">ADCIN </font>1,Duty                    <font color="#008000">' read pot
        </font><font color="#000080">IF </font>Duty&gt;1000 <font color="#000080">THEN </font>Duty =1000    <font color="#008000">' avoid results &gt;1000
        </font><font color="#000080">GOSUB </font>SetPWMDuty                <font color="#008000">' Set PWM duty cycles
        </font><font color="#000080">PAUSE </font>1                         <font color="#008000">' allow few PWM cycles
        </font><font color="#000080">GOTO </font>Start
        <font color="#008000">'
        '---------------------------------------------------------------------------------

        '-------------------------------&lt; Subroutines &gt;-----------------------------------
        '
</font>SetPWMDuty:
        <font color="#008000">'       Datasheet recommend to stop PWM, load duty cycles vale
        '       to avoid possible glitches.
        '
                '
                '       stop PWM
                '       --------
        </font>CCP1CON = PWM_OFF  
                <font color="#008000">'
                '       load Duty values
                '       ----------------
        </font>CCPR1L = Duty &gt;&gt;2   
        CCP1CON.5 = Duty.1
        CCP1CON.4 = Duty.0
                <font color="#008000">'
                '       Start PWM
                '       ---------
        </font>CCP1CON = CCP1CON | PWM_ON              
        <font color="#000080">RETURN
        </font><font color="#008000">'
        '---------------------------------------------------------------------------------
</font>

things to remember, disable the PWM mode, update the duty cycle, start PWM mode and allow few PWM freq cycle.. unless results could be weird.