help with pic 12F509 - Electronic Circuits Projects Diagrams Free

crzy engineer · 13th January 2009, 11:36 PM

i am a tech at this company i work for and one of my engineers asked me to write a program from the schematic he provided me.

ok so this is my question... my first assignment was to write a code that would enable the pic to turn the motor on for 6 seconds when the switch is pressed then turn off to reserve power and again turn on when the swith is pressed again .

i presume it is a NC switch

can anyone help me out with this.

Mike, K8LH · 13th January 2009, 11:56 PM

What PIC part number? I can't quite make it out... Does it say 12F508/509?

nickelflippr · 14th January 2009, 12:01 AM

Use a N.O. switch,like shown here as the RA3/MCLR buttonhttp://ww1.microchip.com/downloads/e...0Schematic.pdf

Pommie · 14th January 2009, 12:03 AM

The place to start is the template file you will find in C:\Program Files\Microchip\MPASM Suite\Template\Code called 12F509temp.asm. You will need to turn off the MCLR pin as your engineer has used it as the input pin.

(change _MCLRE_ON to _MCLRE_OFF).

You will then need to read the datasheet to figure out how to turn on the weak pullup resistors and make GP4 an output. For the delay you can use the Pic Delay Generator and that should get you started.

Mike.

Pommie · 14th January 2009, 12:04 AM

Quote:

Originally Posted by Mike, K8LH

What PIC part number? I can't quite make it out... Does it say 12F508/509?

I guess you missed the title.

Mike.

Mike, K8LH · 14th January 2009, 12:11 AM

Yes I did. Guess I became too focused on the schematic and very curious about the normally closed push button switch (grin)...

crzy engineer · 14th January 2009, 12:24 AM

Quote:

Originally Posted by Pommie

The place to start is the template file you will find in C:\Program Files\Microchip\MPASM Suite\Template\Code called 12F509temp.asm. You will need to turn off the MCLR pin as your engineer has used it as the input pin.

(change _MCLRE_ON to _MCLRE_OFF).

You will then need to read the datasheet to figure out how to turn on the weak pullup resistors and make GP4 an output. For the delay you can use the Pic Delay Generator and that should get you started.

Mike.

Hey mike thanks for the info.

im guessing from what you wrote he made a mistake with the MCLR pin?

crzy engineer · 14th January 2009, 12:39 AM

Quote:

Originally Posted by Mike, K8LH

Yes I did. Guess I became too focused on the schematic and very curious about the normally closed push button switch (grin)...

is there anything wrong with the NC push button?

crzy engineer · 14th January 2009, 12:55 AM

Quote:

Originally Posted by nickelflippr

Use a N.O. switch,like shown here as the RA3/MCLR buttonhttp://ww1.microchip.com/downloads/e...0Schematic.pdf

thanks for the suggestion nickel

Pommie · 14th January 2009, 12:55 AM

There is nothing wrong with using the MCLR pin. It is just unusual as it is normally used after all the other pins are allocated. The only thing wrong with the NC switch is that it will use (slightly) more current than a NO but as you have a motor in the circuit the extra amount is insignificant.

Mike.

crzy engineer · 14th January 2009, 01:02 AM

Quote:

Originally Posted by Pommie

There is nothing wrong with using the MCLR pin. It is just unusual as it is normally used after all the other pins are allocated. The only thing wrong with the NC switch is that it will use (slightly) more current than a NO but as you have a motor in the circuit the extra amount is insignificant.

Mike.

ok i understand what you said. Im thinking he used it because that pin is only an input am i correct?

Pommie · 14th January 2009, 01:49 AM

Yes, it is input only but this suggests that the circuit will be extended to use the other pins. Also, with no MCLR pin and the internal oscillator, some (cheapo) programmers may not be able to reprogram the chip.

Mike.

Oblong · 14th January 2009, 12:40 PM

This guy has the best tutorials on PIC's

heres some for the 12F509.

http://http://www.gooligum.com.au/tut_baseline.html

Thread Tools
Show Printable Version Email this Page
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode

Similar Threads
Title	Starter	Forum	Replies	Latest
Needing help with delay times on a 12f509	Darkstar64	Micro Controllers	16	13th August 2008 11:59 PM

13th January 2009, 11:36 PM	#1 (permalink)
crzy engineer	help with pic 12F509 i am a tech at this company i work for and one of my engineers asked me to write a program from the schematic he provided me. ok so this is my question... my first assignment was to write a code that would enable the pic to turn the motor on for 6 seconds when the switch is pressed then turn off to reserve power and again turn on when the swith is pressed again . i presume it is a NC switch can anyone help me out with this. Attached Thumbnails

13th January 2009, 11:56 PM	#2 (permalink)
Mike, K8LH	What PIC part number? I can't quite make it out... Does it say 12F508/509? Last edited by Mike, K8LH; 13th January 2009 at 11:58 PM.

14th January 2009, 12:01 AM	#3 (permalink)
nickelflippr	Use a N.O. switch,like shown here as the RA3/MCLR buttonhttp://ww1.microchip.com/downloads/e...0Schematic.pdf

14th January 2009, 12:03 AM	#4 (permalink)
Pommie	The place to start is the template file you will find in C:\Program Files\Microchip\MPASM Suite\Template\Code called 12F509temp.asm. You will need to turn off the MCLR pin as your engineer has used it as the input pin. (change _MCLRE_ON to _MCLRE_OFF). You will then need to read the datasheet to figure out how to turn on the weak pullup resistors and make GP4 an output. For the delay you can use the Pic Delay Generator and that should get you started. Mike.

14th January 2009, 12:11 AM	#6 (permalink)
Mike, K8LH	Yes I did. Guess I became too focused on the schematic and very curious about the normally closed push button switch (grin)...

14th January 2009, 12:55 AM	#10 (permalink)
Pommie	There is nothing wrong with using the MCLR pin. It is just unusual as it is normally used after all the other pins are allocated. The only thing wrong with the NC switch is that it will use (slightly) more current than a NO but as you have a motor in the circuit the extra amount is insignificant. Mike.

14th January 2009, 01:49 AM	#12 (permalink)
Pommie	Yes, it is input only but this suggests that the circuit will be extended to use the other pins. Also, with no MCLR pin and the internal oscillator, some (cheapo) programmers may not be able to reprogram the chip. Mike.

14th January 2009, 12:40 PM	#13 (permalink)
Oblong	This guy has the best tutorials on PIC's heres some for the 12F509. http://http://www.gooligum.com.au/tut_baseline.html