Can't get COUNT to count

[jellis00]

One part of my program won't work where I am using the COUNT command to count input pulses on an input pin. I know it isn't actually seeing any pulses and counting them because I am writing the count variable to EEPROM and then reading the EEPROM address after running the program. It continuously shows the value that was written to the EEPROM address as 0 (zero). I double checked to make sure that TRISA = $02 in my Register Settings so that RA1 is set to bit 1 and RA3 is set to bit 0.
Can anyone tell me what is wrong with this code that keeps COUNT from counting input pulses?
Thanks!

' Start measuring output of flow meter at RA1 input pin
    i = 1           ' Preset pulse counter index to zero
    WHILE i <= 10 'Assume the value CIN is a pulse count from the sensor
        'Count the number of pulses from Hall Effect Magnetic Sensor in 10 sec
        Count PORTA.1,10000,CIN
        WRITE 5,CIN                ' Write count into EEPROM location 5
        'Slowly blink LED during water flow  
           HIGH PORTC.0             ' If we get here, Blink the LED slowly
           PAUSE 200
           LOW PORTC.0
           Sleep 2              ' Wait 2 seconds
        i = i + CIN              ' Increment pulse count for last 10 sec
    WEND        'When i = 10, required gallons have flowed by the meter

[mackrackit]

TRISA = $02 in my Register Settings so that RA1 is set to bit 1 and RA3 is set to bit 0.

The above is pretty much TRISA= %10. Do you see the possible problem?

And with out more info.. Chip and configs and ... I will have to assume for now.
http://www.picbasic.co.uk/forum/showthread.php?t=561

[Dave]

jellis00, You know that the returned value from COUNT is a 16 bit value? I see you are only writing 1 byte of it to eeprom.. That limits the reading stored to 0 to 255 counts.. And its only the lower byte so it will roll over up to 255 times...

Dave Purola,
N8NTA

[jellis00]

Thanks for that catch, Dave. I fixed it by writing both CIN.Byte0 and CIN.Byte1 into EEPROM, but both addresses have zeros in them after running the program, so COUNT is still not counting pulses into the CIN variable.

I will post my code in another reply, including declaratons as suggested to see if any of you can see my problem.

[jellis00]

Mackrackit, my chip is a PIC16F690 as installed in a PICkit2. I am using PICBasic Pro as the programming language and MicroCode Studio as the programming IDE to the PICkit2. I will post my code at end of this posting in hopes you can help me determine whaI I am doing wrong.
I didn't quite understand your implication about the register setting for setting RA1 to bit 1. I read the link you provided and I guess what you are saying is that I should set the register for all A/D to digital....??

I read the data sheet for the PIC16F690 regarding setting the A/D to digital and saw a warning that connecting some analog signals to the input pin when it is set to be a digital input can damage the input. This caused me to measure the analog signal coming from the meter and it generates a pulse it is a +5.0 volt pulse. This is the same as VDD and within the specified max input voltage for the PIC16F960, so I don't think it would have damaged the chip....your opinion?? For this kind of input signal from the meter, should I set the register for all digital or all analog?? Since COUNT measures a pulse on the rising input signal, I presumed it would count each pulse input from the meter.

I have made the changes suggested by Dave and also redid the ADC register settings as I understand them. Here is my code, some of it only stubbed out with pseudo code comments. It all works as intended except for the segment that requires COUNT to read the input pulses from PORTA.1 (RA1 pin). Can you please review and advise me where I am going wrong and why the COUNT statement is not actually counting any of the input pulses into the variable CIN??

I greatly appreciate your help.

'**************************************************************************
'*  Name    : Meter.BAS                                            *
'*  Compiler: PICBASIC PRO Compiler microEngineering Labs                 *
'*  Author  : John R. Ellis                                               *
'*  Notice  : Copyright (c) 2009 LodeStar Associates, Inc.                *
'*          : All Rights Reserved                                         *
'*  Date    : 3/23/2009                                                   *
'*  Version : 1.07                                                         *
'*  This Program is for a PIC16F690 installed in a PICkit2 Starter Kit    *
'*  Purpose: 1)  Monitor an input for an external Interrupt*
'*          2)  On Interrupt, command latching solenoid to open valve *
'*          3)  Measure flow meter output to determine when required no.      *
'*                  gallons have passed                                   *
'*          4)  On required gallons command latching solenoid to close    *
'*           5)  Put Microcontroller back in Sleep State to await next *
'*                  Interrupt                                       *
'**************************************************************************
'Device Declaration
@device pic16F690, intrc_osc_noclkout, BOD_OFF, PWRT_OFF, wdt_off,mclr_off,protect_off
 
'EEPROM PRESETS
DATA @0,0
 
'OSC DEFINE
DEFINE OSC 4
 
'Variables Declarations
led  VAR PORTC.0    ' Set RA0 as output pin for LED
valve VAR PORTC.3   ' Set RA3 as output pin for pulse to valve solenoid
meter VAR PORTA.1   ' Set RA1 as input pin for Hall Sensor meter input pulses
 
'Registers Settings
TRISA = %00000010   ' Set PORTA.1 pin to input 
TRISB = 0           ' Set all PORTB and PORTC pins to outputs
TRISC = 0
ADCON1 = 15         ' Set all ADC pins to digital....SHOULD THIS BE SO????
PORTC = 0   ' Preset LEDs off
PORTA.1 =0          ' Pre-set RA1 at Low value
 
'Variables Initialization
 switchstate    VAR Bit ' Stores value of last measured switchstate
 k             CON 30  ' Calibration factor for flow meter...# pulses per gal
 i              VAR Byte    ' Index used in Gallon counter While loop
 CIN           VAR Word    ' Storage variable for count from COUNTER

'Set INT Handler
'ON INTERRUPT GOTO in_sig   'Provision for future interrupt input..commet out
 
'Start...normal code here
MAIN:
    switchstate = 1  ' Preset interrupt simulation Switch State
    'SLEEP = 65,535  ' Place in sleep state at startup..commented out in test 
    ' Microcontroller is in Sleep State waiting for external Interrupt
 
    'This code segment simulates external interrupt switch
    '*** Read State of Switch with 100 msec Debounce
    loop: 
 if PORTA.3 = 0 then    'Interrupt Switch is pressed on RA3 input
  pause 100     'Delay 100 msec
  if PORTA.3 = 0 then   'Test switch again for switch bounce
  switchstate = ~switchstate 'Toggle Switch State Flag
   hold
   if PORTA.3 = 0 then hold 'Wait for switch to be released
   goto in_sig       'Switch pressed...simulates external interrupt
  endif
 endif
    Goto loop       'If notpressed, monitor switch input
 
in_sig:
    'Interrupt handler code here when actual external interrupts implemented
    'Disable                 ' No interrupts past this point
 
    'Put code here to Wakeup the Microcontroller from SLEEP on interrupt
    
    ' Put code here to start a timer to run for 50 secs as a fail safe to prevent
    ' overflow of tank in case of sensor failure...goes to Stop label on timeoout
    
    'Send PWM pulse to latching solenoid to open valve
        'Generates 10 millisec pulse on RC3 output pin
         'LOW PORTC.3            ' Initialize output pulse polarity
         PULSOUT PORTC.3,1000   ' Generate 10 msec pulse to RC3               
  
    ' Valve should be open at this point and water flowing
            
    ' Start measuring output of flow meter at RA1 input pin
    i = 0           ' Preset pulse counter index to zero
    WHILE i <= k 'Assume the value CIN is a pulse count from the sensor
        'Count the number of pulses from Hall Effect Magnetic Sensor in 10 sec
        COUNT PORTA.1,10000,CIN
        WRITE 5,CIN.Byte0                ' Write 10 sec count into EEPROM
        WRITE 6,CIN.Byte1
        'Slowly blink LED during water flow  
           HIGH PORTC.0             ' If we get here, Blink the LED slowly
           PAUSE 200
           LOW PORTC.0
           Sleep 1              ' Wait 1 seconds
        i = i + CIN.Byte0         ' Increment pulse count for last 10 sec
    WEND        'When CIN = k, required gallons have flowed by the meter
Stop:
    ' Put code here to command solenoid to shut valve
END

[jellis00]

Found my problem after an email from melLabs tech support.

I needed to set all inputs as digital by configuring all pins digital on the 16F690 by setting ANSEL = 0 and ANSELH = 0 in my Register Settings. Once I did this, everything works!
This also answers my question about whether the input from the meter sensor needs to be set as an analog or digital input. Evidently, even though the input is an analog pulse, since it is within the max limits for digital input, having the input pin as digital is OK and precludes having to use code to sample the signal input with the A/D to determine the pulse presence that way. Don't quite understand why a digital input works with an analog signal, but if it works I won't argue with it.

[Archangel]

Found my problem after an email from melLabs tech support.

I needed to set all inputs as digital by configuring all pins digital on the 16F690 by setting ANSEL = 0 and ANSELH = 0 in my Register Settings. Once I did this, everything works!
This also answers my question about whether the input from the meter sensor needs to be set as an analog or digital input. Evidently, even though the input is an analog pulse, since it is within the max limits for digital input, having the input pin as digital is OK and precludes having to use code to sample the signal input with the A/D to determine the pulse presence that way. Don't quite understand why a digital input works with an analog signal, but if it works I won't argue with it.

Hi jellis00, I gotta disagree about the signal being analog inasmuch as you are counting the tops of the waveforms of the hall effect switch. Your post stands as a wonderful example of why you want to read everyone else's posts even if their problem seems unrelated to your own problem, here is why: I just addressed this problem (ANSEL & ANSELH) here: http://www.picbasic.co.uk/forum/showthread.php?t=10788 Using the same development board and PIC.
It might have saved you some hair Speaking only for myself, I do not have any extra to lose ! I am happy you found the problem.