12f675_fuse_about_to_blow!

[cncmachineguy]

First let me say, this is an awesome thread. I have been meaning to read it from the beginning, but I am a slow reader.

LEDave, WDT in the snippet you just posted works like this:
Assuming PBP knows you are using the WDT, clear WD is sprinkled around the program for you to keep from resetting the chip. But to get to these, the program must run.

@sleep basically stops the program and the chip just, well sleeps. Because of this, the WDT never gets cleared. The WD can wake up the PIC, so when WDT overflows, the PIC wakes up and resumes where it left off. So this is how the WDT is associated with the counter.

Hope this helps

[mackrackit]

Bert,
will this make it work as expected?

WHILE COUNTER <= 2      ' 4.608sec Loop time (Loop for 30 mins = 781)
      INTCON.0 = 0
     @ SLEEP
    CLEARWDT
     COUNTER=COUNTER+1
     'IF  GPIO.3= 0  THEN COUNTS 'Bird at box (it's not dark) so continue counting
WEND

[cncmachineguy]

Dave, sorry for being only clear as mud with my explaination. I ment to say : because of this, the WD never gets cleared WHILE SLEEPING. When the pic is asleep, WDT overflows thus waking up the PIC.

I tried to quickly look over the program a few posts up, but I don't have a good feel for it yet. I don't think adding the CLRWDT will help only because when the pic wakes, it should be a long time (~2sec) before the next overflow.

I did notice when @SLEEP is used elsewhere in the program, the line following is @NOP. Maybe this is needed to give the pic a chance to get the sleep from its eyes? I would try using @NOP right after the @SLEEP and see if this works.

I have never used any of the power saving modes before, but if the pic needs a nop upon waking up, it may be ignoring the counter=counter+1. Therefore the while is never satisified.

In any event,if the NOP is needed, adding CLRWDT may solve the problem, we just won't know why it did.

[LEDave]

Hi Bert

Thanks for your input and welcome to the thread. I was heading towards the CLRWDT after reading this (quite an interesting website):

http://www.hobbyprojects.com/pic_tut...utorial13.html

Well here's the section of code as it stands:

DARK:   
      'INTCON.0 = 0    ' Clear int on change flag
                       ' It could be night time...It might only be a cloud though...   
                       ' so back to sleep / wake / sleep for half an hour..zwzwzw
      
      COUNTER=0        ' clear before entry
WHILE COUNTER <= 2     ' 4.608sec Loop time (Loop for 30 mins = 781)
     INTCON.0 = 0      ' Clear int on change flag
     @ SLEEP
     @ NOP 
     CLEARWDT
     COUNTER=COUNTER+1
     'IF  GPIO.3= 0  THEN COUNTS 'Bird at box (it's not dark) so continue counting
WEND     
                   
    if  GPIO.4= 0  then ENCODE  ' It really ia dark so carry on and transmit VISITS
    
    'IF  GPIO.4= 1  THEN Main  '(changed from return) It's not dark after all so carry_on_sleeping_counting 
    
Encode:  
    E_OUT=1     ' Turn transmitter on

What happens now is when the push button on GPIO.4 is pressed (and held down) After a count of 9 seconds approx (I was expecting a count of two to give half that time) the TX board led lights but still nothing is transmitted.

The program still doesn't seem to get to encode and transmit, frustrating, any other thoughts?

Dave

[LEDave]

Bert

As an aside to the problem, earlier on in the program we have:

Main:    
    ' Read port to clear missmatch, if with no buttons pressed, then
    ' clear int-on-change flag & snooze until wake up on change. This
    ' conserves battery power on the demo board with 3V coin cell.
    
  IF GPIO.3= 1 AND GPIO.4= 1 THEN ' Nothing has happened so SLEEP
       E_OUT=0       ' Disable transmitter
       INTCON.0 = 0  ' No Inputs detected or it's still light so clear int on change flag
       @ SLEEP       ' and start snoozin..zzzzzzzzzzz indefinatly
       @ NOP         ' Do nothing for 1st instruction on wake-up
  ELSE  
   'IF  GPIO.3=0 THEN GOSUB COUNTS 'Bird detected at box - GOTO LABEL COUNTS   
   IF  GPIO.4=0 THEN DARK   'It's got dark? or just cloudy - GOTO LABEL DARK
  ENDIF     
  GOTO MAIN          'Back to sleep / continue counting

Does this mean that using a WDT and a SLEEP command to save power are kind of mutually exclusive? The SLEEP command turns the PIC off (saving power) then the WDT turns the PIC back on again 4.6seconds later in our case? The above code would keep looping on and off until a button is pressed or the 3v cell goes flat?

Dave

[LEDave]

Have spent several interesting but largely fruitless hours trying to make some progress with the program.

However if I jump passed the COUNTER / WDT routine the TX & RX work fine which is good to know.

Here's the code for it:

      COUNTER=0        ' clear before entry
WHILE COUNTER <= 2     ' 4.608sec Loop time (Loop for 30 mins = 781)
     INTCON.0 = 0      ' Clear int on change flag
     @ SLEEP
     @ NOP 
     CLEARWDT
     COUNTER=COUNTER+1

One thought does occur to me though, at the start of the program the PIC is placed into SLEEP mode, only to be woken on INTERRUPT.

Code below.

IF GPIO.3= 1 AND GPIO.4= 1 THEN ' Nothing has happened so SLEEP
       E_OUT=0       ' Disable transmitter
       INTCON.0 = 0  ' No Inputs detected or it's still light so clear int on change flag
       @ SLEEP       ' and start snoozin..zzzzzzzzzzz indefinatly
       @ NOP         ' Do nothing for 1st instruction on wake-up
       CLEARWDT
  ELSE  
   'IF  GPIO.3=0 THEN GOSUB COUNTS 'Bird detected at box - GOTO LABEL COUNTS   
   IF  GPIO.4=0 THEN   encode 'DARK 'Encode 'DARK   'It's got dark? or just cloudy - GOTO LABEL DARK

However, GPIO.4 must be pressed and held down (simulating night time) which causes the wake up from SLEEP interrupt, the program then moves down to the COUNTER / WDT loop. I think I might have found a problem here though. For the COUNTER / WDT loop to work and give a 4.6sec test delay the PIC must go into SLEEP mode, if GPIO.4 is continually held down simulating night time and hence causing an INTERRUPT from SLEEP (continually, even resetting the interrupt won't help as button continually pressed) then my thinking says the COUNTER /WDT loop will never work because the PIC is always being woken up.

A bit garbled I know, sorry, but am I onto something.

Dave

[LEDave]

I'm having a problem getting the rfpic transmitter to Tx when I want it to. I've set up an ON INTERRUPT with DISABLE - RESUME - ENABLE and have the INTCON & IOC set at:

INTCON = %00001000 & IOC = %00011000

What happens is, when buttons GPIO3/4 are pressed (and released)the RFEN led after a 5sec delay briefly flashes but no data is sent. If GPIO.3/4 are pressed and held down after 10 secs the RFEN led lights up the five seconds later (button still held down) data is Tx'd, the button is then released and five seconds later the RFEN led goes out.

What I'd like is for the buttons GPIO.3/4 to be pressed, ON INTERRUPT runs then five seconds later after the delay loop the data is Tx'd. Does anyone have any idea on what's going wrong?

@ __config _INTRC_OSC_NOCLKOUT & _WDT_OFF & _MCLRE_OFF & _CP_OFF
 
    DEFINE OSC 4
    DEFINE OSCCAL_1K 1
    DEFINE NO_CLRWDT 1    
 
    SYMBOL D_OUT = GPIO.2 ' RF serial data output
    SYMBOL E_OUT = GPIO.5 ' RF transmitter enable output
 
    ON INTERRUPT GOTO  Delay
 
    DAT_OUT  VAR BYTE   ' Holds 8-bit data byte
    CHK_SUM  VAR BYTE   ' Holds calculated checksum of outbound data
    VISITS   VAR WORD   ' Loop variable (300 for test)
    I        VAR word   ' Delay Loop Count value  
    BAUD     VAR WORD   ' Holds baud rate
 
    ' Constants
    PreAmble CON $A5    ' 10100101 preamble
    Synch    CON "~"    ' 01111110 synch byte
    N4800    CON 188    ' 4800 bps 
    N2400    CON 16780  ' 2400 bps
    GUARD    CON 5      ' 5mS guard time pause
 
 
    ' hardware init 
    GPIO = 0            ' Everything off on boot
    ' GPIO.2=data out, GPIO.5=RF enable, GPIO.3,4 = Bird_visit_count / It's dark..maybe
    TRISIO = %00011011  '
    ANSEL = 0           ' Disable A/D
    INTCON = %00001000   ' Enable port change wakeup from sleep
    WPU = %00010000     ' pull-up on for GPIO.4 (external pull-up already on GPIO.3)
    IOC = %00011000     ' Wakeup on change enabled for GPIO.3,4
    VRCON = 0           ' Disable internal Vref
    CMCON = 7           ' Disable comparators
    OPTION_REG = 0      ' Pull-ups on 
 
    D_OUT = 0           ' Idles low for inverted serial output
    E_OUT = 0           ' Enable for RF transmitter=0 (transmiter off)
    BAUD = N2400        ' Set baud rate here
 
Main:
    ' Read port to clear missmatch, if with no buttons pressed, then
    ' clear int-on-change flag & snooze until wake up on change. This
    ' conserves battery power on the demo board with 3V coin cell.
    IF GPIO.3= 1 AND GPIO.4= 1 THEN ' Nothing has happened so SLEEP
       E_OUT=0       ' Disable transmitter
       INTCON.0 = 0  ' No Inputs detected or it's still light so clear int on change flag
    @ SLEEP          ' and start snoozin..zzzzzzzzzzz indefinatly / Waiting for IOC
    @ NOP
    'ON INTERRUPT starts / returns here with Button_press: goes to LABEL - "DELAY":
 
ENDIF
Encode: 
 E_OUT=1     ' Turn transmitter on 
    pauseus 25  ' Let transmitter settle
    DAT_OUT = %10101001
 
    'Build checksum of 2 data bytes
    CHK_SUM = (DAT_OUT * 2) 
 
Transmit:
   'LET VISITS = VISITS / 2  'Just VISITS too not from the box 
    LET VISITS = 300 'Test data number
     SEROUT2 D_OUT,BAUD,[PreAmble,Synch,DAT_OUT,DAT_OUT,CHK_SUM,VISITS.highbyte,VISITS.lowbyte]
     PAUSE GUARD ' 5mS guard time gives decoder time to respond,calculate,change,etc.
     GOTO Main 
 
disable 
 
Delay:
FOR I = 1 TO 5
    PAUSe 1000
nEXT I 
INTCON.0 = 0 
resume : enable 
goto Main

Dave