pause puts me in sleep mode

[EDWARD]

Its Edward again, with yet another problem.

i have a solenoid being driven by a NPN transistor. the base of the NPN is conneted to portc.2 if i make portc.2 output high it will turn on the solenoid as expected. i also have a push button connected to portb.0.
the goal is to turn on the solenoid for a short deley then turn off.

now comes the problem

when i use the PAUSE command it puts my pic 16f73 into low power mode or something, cause i only read ~3.5 volts on the vdd.

below are the two codes.
both codes work when led+resistor unit replace solenoid (no solenoid)
one works the other does not when solenoid is connected (solenoid)

'works


TRISC=235 'set PORTC as output on needed pins
TRISB=251 'PORT B INPUT EXCEPT on uneeded
'------------------------------------
MAIN:

PORTC=%00010000 'PWR LOCK-ON & solenoid data low

IF PORTB.0=1 THEN 'BUTTON 2 IS PRESSED ACTIVATE SOLENOID
GOTO SHOOT
ENDIF

IF PORTB.4 = 1 THEN 'BUTTON 1 IS PRESSED THEN EXIT
GOTO EXIT
ENDIF

GOTO MAIN
'---------------------------------------------------
EXIT:
PORTC = %00000000 'LOW PORTC all PWR OFF
END
'---------------------------------------------------

SHOOT:
PORTC.2 = 1 'SOLENOID ACTIVE
GOTO MAIN
'-------------------------------------------------








'doesnt work below

TRISC=235 'set PORTC as output on needed pins
TRISB=251 'PORT B INPUT EXCEPT on uneeded
'------------------------------------
PORTC=%00010000 'PWR LOCK-ON

MAIN:
IF PORTB.0=1 THEN 'BUTTON 2 IS PRESSED ACTIVATE SOLENOID
GOTO SHOOT
ENDIF

IF PORTB.4 = 1 THEN 'BUTTON 1 IS PRESSED THEN EXIT
GOTO EXIT
ENDIF

GOTO MAIN
'---------------------------------------------------
EXIT:
PORTC = %00000000 'LOW PORTC all PWR OFF
END
'---------------------------------------------------

SHOOT:
PORTC.2 = 1 'SOLENOID ACTIVE for 1/5 seconds
PAUSE 200 '<- RIGHT HERE RIGHT HERE RIGHT HERE IS PROBLEM!
PORTC.2 = 0
GOTO MAIN
'-------------------------------------------------


lastly when i disonnect the solenoid everything works fine again without a need to reset the pic. so the working model only alows the solenoid active AS LONG AS IM HOLDING BUTTON 2 DOWN. not a desired function i want the solen active for x number of seconds then off.

2 things come to mind.

1. if it was a hardware problem, why would it work just fine without the pause command.

2. when i tell portc.2 = 0 could that effect anyother pin on the portc?

u should also know that i have a "power on" command. becaue my boards power button is momentary button, the board was desgned that as long as portc.4 is high the vdd will be 5+. the board basically works like this.

1 press and hold pwr momentary button.
2 that sends 5+ to the pic and it starts the program
3 in the program I put portc.4 = 1 so that the vdd Locks-On
4 to power off pic just portc.4 = 0 or all of portC=0
5 that makes a transistor somewhere "off"

sory if i made this one too long.

[NavMicroSystems]

EDWARD,

I guess the problem is hardware related.
We would need to have a look at the schematic to further analysis.

Questions:

1. Where does the Solenoid get it's power from?
2. Do you have a Resistor between PortC.2 and the Base of the NPN?
3. Do xou have a reverse Diode across the Solenoid?
4. As your Buttons read "1" when pressed, do yo have PullDown Resistors on the corresponding PIC Pins?

Is this the same strange Board you had the LCD questions on?

[EDWARD]

yes it is the same board witht the lcd. i dont have the schematics for the board. the board has al surface mount components and i am trouble telling what ALL the parts are. i have figured alot out but not everything. i know the hardware will work because these boards have porgrams on them right now and work fine with the old code. i have erased one of them to use as my "test board" and have made no hardware changes.

the designer of the board, as it seems, did many things wrong. the designer

1:did not use a resistor on the soleniads npn base.

2:doesnt have any resistors to the inputs on portB, which cantains most
input buttons.

3: i think that there is a diode across the solenoid though.

4:solenoid is a 5vdc. it is driven by sinking. i got 9 volt going to a Vreg 5+, an that 5+ going to the red wire of the solenoid. the black wire goes to the collector of the npn.

( i am going to make a picture/table. im also going to try and create a schemati for you.)

[mister_e]

probably the transistor in use is a digital type with internal resistor or logic mosfet. that's why you don't have any external resisotr.

no resistor on PORTB... probably the internal pull-ups where in use. I bet the pushbutton are between PIC and gnd!

The major cause, as i suspect, might be the current provided by the power supply, must be unsufficient to make the 5 volt line goes to 3.5 volt. Use another power supply.

[EDWARD]

thanks for your response mister_e. i know that the hardware is sufficient for my purposes, but oddly enough the buttons are actually between 5+ and pic,weird.

also, i bought bunch of 9 volts, and still same problem. this only happens when i use the pause command. if the solenoid is programmed to ONLY BE ON WHEN THE BUTTON(on a different port) IS HELD TRUE, it works fine. but if i tell the solenoid to stay high for 1 seconds (PAUSE 1000) the vdd drops to 3.5. dang!

is it possible that some of the power to "help" drive the solenoid and/or PIC, comes from a data port? conversly, will defining (TRISX) to many pins as outputs (not necessarily HIGH), will draw excesive current?

[EDWARD]

ok guys i made a breakthrough of "KFC snacker size" proportions.

OK so im hungry and not funny. but i am gaining on my pause problem.
today i found out that if i short out portc.2 it will "turn off" my solenoid "driver" the only way for the driver to turn fully off is to short it. portc.2 =0 doesnt go low enough.

secondly, i found out how the driver works. my solenoid red wire is connected to a 5+, and the black wire of the solenoid is connected to 2 transitors in parallel. one of the transiters set the sink bias to make the solenoid "driver" at a 4.4 volts on the ground side, even when portc.2 is low. and when portc.2 goes high, it sinks the solenoid over 5+. thereby fireing the solenoid.

This has led me to beliver that when i ground out the portc.2 pin, which in turn turns off the driving transistor, which turns off the solenoid.

that can only mean that when i put portc.2 = 0 it is not going low enough. how do i make portc.2 less than 0 it really wierd cause as soon as i short portc.2 with my vdd goes back up to 5+.

ive tried swapping solenoids and batteries.