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Sands.Ov.Time
Joined: 12 Jul 2010
Posts: 4
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| Remote garage door opener |
 Posted: Sat Jul 17, 2010 1:23 am |
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I intend to build a simple remote garage door opener: the owner enters a security code on the keypad of the remote control, and the receiver/control panel compares this code with the stored one.
There is a lot of documentation on the Manchester coding, RX/TX433 using rs232, but I need no PC interfacing so I wonder how I can send/receive the data/password in this project.
Which sections would you recommend from the CCS c manual?
Any links or advice would be helpful.
Thanks.
version: 4.057
Transmitter (PIC16F877,4*3 Keypad,TX433):
Receiver(PIC16F877,4*3 Keypad,RX433, 2*16LCD LM016L):
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Abdulla M.A.
Joined: 28 Mar 2010
Posts: 30
Location: Baghdad, Iraq
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| Posted: Sat Jul 17, 2010 4:21 am |
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Notes:
1- your circuit will not work, because you did not connect pull-up
resistors to the keypad.
2- the 5v should connect to Mclr across 10k resistor
3- you need a current limiting resistor to the LED
4- Oscillator require like a crystal.
Abdulla
_________________
"A scientist can discover a new star, but he cannot make one. He would have to ask an engineer to do that."
"For an optimist the glass is half full, for a pessimist it's half empty, and for an engineer is twice bigger than necessary." |
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Sands.Ov.Time
Joined: 12 Jul 2010
Posts: 4
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| Posted: Sat Jul 17, 2010 5:48 am |
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Thanks for your reply Abdulla, your notes are crucial.
| Quote: | 1- your circuit will not work, because you did not connect pull-up
resistors to the keypad |
I think the "port_b_pullups(True)" in the c code would solve it.
Anyway I updated the schematics according to your notes.
| Quote: | | 4- Oscillator require like a crystal. |
Can you explain more please?
Receiver (Updated):
Transmitter (Updated):
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Abdulla M.A.
Joined: 28 Mar 2010
Posts: 30
Location: Baghdad, Iraq
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| Posted: Sat Jul 17, 2010 11:59 am |
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Check the circuit connection in the link below.
http://sites.google.com/site/abdulla877/about/pic-tutorials/auto-power-off-circuit
Abdulla
_________________
"A scientist can discover a new star, but he cannot make one. He would have to ask an engineer to do that."
"For an optimist the glass is half full, for a pessimist it's half empty, and for an engineer is twice bigger than necessary." |
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Sands.Ov.Time
Joined: 12 Jul 2010
Posts: 4
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| Posted: Sat Jul 17, 2010 8:00 pm |
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Thanks a lot.
I have updated the schematics.
I am still wondering if I can use the functions and directives of the rs232 I/O even if there is no pc interfacing, otherwise can I have some advice just to clarify my confusion and get started in programming.
Thanks.
Receiver (Updated):
Transmitter (Updated):
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PCM programmer
Joined: 06 Sep 2003
Posts: 21708
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| Posted: Sat Jul 17, 2010 8:04 pm |
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| Quote: |
I am still wondering if I can use the functions and directives of the rs232
I/O even if there is no pc interfacing.
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The PC is just another piece of RS-232 terminal equipment. It's not
required. Two micro-controllers can talk to each other with their serial
ports, and there is no PC involved.
My suggestion is first get your project working without the RF links.
Just connect one PIC's serial port to the other (Tx to Rx). When it's
working, then put the RF links in. It will be a lot easier that way. |
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Sands.Ov.Time
Joined: 12 Jul 2010
Posts: 4
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| Posted: Sat Jul 17, 2010 8:25 pm |
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| Quote: | The PC is just another piece of RS-232 terminal equipment. It's not
required. Two micro-controllers can talk to each other with their serial
ports, and there is no PC involved. |
It is much clearer now, I finally can start programming.
| Quote: | My suggestion is first get your project working without the RF links.
Just connect one PIC's serial port to the other (Tx to Rx). When it's
working, then put the RF links in. It will be a lot easier that way. |
Thank you very much, this will help me a lot. |
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