Is it possible to interpret non-standard serial data with PicBasic (sample attached)

[CuriousOne]

This is quite strange, because I'm using 16F1829, running at 16mhz. DEFINE OSC is correct, I've launched series of pulses with 1ms duration, and checked by scope - all correct.

[CuriousOne]

Modified HighTime routine too:

MeasureHigh:
  HighTime = 0
  While Signal = 0 : WEND	  ' Wait for low  
    While Signal = 1              ' Measure high level
    HighTime = HighTime + 1       ' Resolution is 100us, change if needed
    PauseUS 92                    ' Tweal to calibrate, depends on actual loop time
  WEND
  LCDOUT $FE,$c0, "T2:",DEC hightime, "  "
RETURN

it returns 9.

Feels like MCU is operating very slow?

[richard]

what are you expecting to see ?
how many times do you think 100uS will divide into a shade less than 1mS ?

[CuriousOne]

Where it should returned something like 9000, it returns 600, is not this strange?

[richard]

I've launched series of pulses with 1ms duration, and checked by scope - all correct

the code is expecting 10 mS pulse

[HenrikOlsson]

I goofed there. Since the BitArray actually consists of two WORDs and you want the least and most significant WORD of that array the declaration should read

LSB VAR BitArray[0]
MSB VAR BitArray[1]

Where it should returned something like 9000, it returns 600, is not this strange?

What should return 9000?
You've changed the MeasureHigh routine so it only adds 1 each time thru a loop that (ideally) takes 100us to execute. A pulse lasting for 10ms will (ideally) cause that loop to execute 100 times, you end up with 100 in (instead of 10000) in HighTime.

/Henrik.

[richard]

I modified henriks code an tested it with my simulation , works fine

'****************************************************************
'*  Name    : deMODULATOR.BAS                                   *
'*  Author  : richard's modified version of henriks             *
'*  Notice  :  2016                                             *
'*          : All Rights Reserved                               *
'*  Date    : 10/10/2016                                         *
'*  Version : 1.0                                               *
'*  Notes   : decodes missing pulse encoded data stream A.5     *
'*          : 16F1825                                           *
'****************************************************************
  #CONFIG
             __config        _CONFIG1,    _FOSC_INTOSC & _CP_OFF & _WDTE_ON  &  _PWRTE_ON  &  _MCLRE_ON  & _CLKOUTEN_OFF
              __config      _CONFIG2, _PLLEN_ON & _LVP_OFF            
#ENDCONFIG
 
OSCCON=$70 
DEFINE OSC 32



'                       PIC 16F1825



    TRISA     = %111110	 ' Make somepins Input 
    trisc     = %111100  ;Make some pins Input   
    ANSELA=0     
    ANSELC=0
    led var latc.0      ;DEBUG
    led2 var latc.1      ;DEBUG
    demod var porta.5     ;demod in
    X VAR byte
    darta   VAR byte[4] 
    counter var word
    dm_state   VAR byte
    lata.0=1             ;DEBUG
    clear
    led=0
    DEFINE DEBUG_REG PORTA
    DEFINE DEBUG_BIT 0       
    DEFINE DEBUG_BAUD 9600
    DEFINE DEBUG_MODE 0     
    pause 2000
    Debug "Start",13 ,10  
    DEFINE PULSIN_MAX 9000

Code:
HighTime  VAR WORD
LowTime   VAR WORD



WaitForStartBit:
    GOSUB MeasureLow
    
    IF (LowTime < 9500) OR (LowTime > 11000) THEN WaitForStartBit    ' 9.5-10.5ms qualifies
    led2=1
    GOSUB MeasureHigh
    IF (HighTime < 1500) OR (HighTime > 2500) THEN WaitForStartBit    ' 1.5-2.5ms qualifies
    led2=0
    NextLevel:
    For x = 0 to 31
        GOSUB MeasureLow
        IF     LowTime < 1000   then
            darta .0[x] = 0 
        else
            darta .0[x] = 1  
        endif
    NEXT
    led=1
    Debug 13 ,10 ,bin8 darta[3],bin8 darta[2],bin8 darta[1],bin8 darta[0]    ;DEBUG
    Pause 1000
    led=0
    Goto WaitForStartBit

MeasureLow:
  LowTime = 0
  While demod = 1 : WEND         ' Wait for low level
  While demod = 0                ' Measure low level
    LowTime = LowTime + 100       ' Resolution is 100us, change if needed
    PauseUS 92                    ' Tweak to calibrate, depends on actual loop time
  WEND
RETURN

MeasureHigh:
  HighTime = 0
  While demod = 0 : WEND	  ' Wait for low  
    While demod = 1              ' Measure high level
    HighTime = HighTime + 100       ' Resolution is 100us, change if needed
    PauseUS 92                    ' Tweal to calibrate, depends on actual loop time
  WEND
RETURN