Linux infrared remote control

1. 2010 by storm
Communications project
lirc = Linux infrared
remote control

2. Part of presentation
Introduction Component Faced
to the project and criteria problems
lirc

3. INTRODUCTION TO THE
PROJECT
lirc

4. Getting Started introduction
lirc =>
Linux infrared remote control
Serial Port Receivers
reference
http://www.lirc.org/receivers.html

5. Use remote !
Use remote to send an IR signal and receive it
in designed circuit and the control any thing
in computer by a software .

6. COMPONENT AND
CRITERIA
lirc

7. Components !
C1 - 4.7µF capacitor

8. Components !
D1 - 1N4148 diode

9. Components !
R1 - 4k7 resistor (4.7 kOhm)

10. Components !
IC2 - 78L05, 100mA, voltage regulator (TO-92 casing)

11. Components !
9-pin or 25-pin SUB-D socket

12. Components !
Tsop 1738

13. Criteria
You should choose the 38 kHz carrier frequency types because
most remote control standards use this frequency.
What happened if we use receiver with lower frequency ?
The receiver won't stop working if your remote uses another
frequency but the range will decrease.

14. Criteria
The pin-out of the voltage regulator
usually looks like this (front view)
The pin-out of the tosp receiver usually
looks like this (front view) 1,2,3 from left

15. Criteria
Serial port distribution looks like this

16. Criteria
The circuit of all receiver

17. Criteria
The power for the circuit comes from the RTS (request to send )
line of the serial port. D1 protects the circuit from the negative
voltage that is usually on the RTS pin. The LIRC driver will change
the serial port settings on initialization so that the circuit will get
the necessary positive voltage. For most standard PC serial ports
this will be approximately 10V. IC2 will convert the input voltage
to exactly 5V.

18. Criteria
C1 is optional but for safety.
R1 is a pull-up that makes sure the DCD (Data carrier detect) line is on a
valid voltage level if the receiver does not receive anything.

19. Criteria
When an infrared signal is detected pulls DCD (Data carrier detect)
down to ground, which should already be interpreted as a logical "1"
(DCD=0) by the serial port.

20. Faced problems
lirc

21. Faced problems
1
* Due to low voltage in serial port that (6V or even less)
out from regulator 2v
this circuit probably won't work on some notebooks
So you should make sure that your serial port delivers
at least 8V of output voltage

22. Solution
If your serial port provides less you can also try
using a low-drop voltage regulator (e.g. LP 2950
CZ) instead of the regulator suggested here

23. Faced problems
2
* we can't use USB to serial converter
the USB port or the internal 5V line to power the
circuit.

24. Then you won't need a voltage regulator at all.