Anyone any experience of Consumer Infra Red (CIR) devices? [Long]

[David WE Roberts]

On the MoBo of my new PC I have (amongst others) two headers:

IR (which presumably is for IRDA) CIR

AIUI IRDA is for two way communication between smart devices and has a properly structured open standard protocol stack. CIR is for remote controls and has no standards as such (although the most common proprietary protocols seem to be fairly well known) - it is just a serial bit stream to pass key strokes from a remote control to a consumer electronic device such as a TV or HiFi component.

Now I would like to use the PC as a Home Theatre component and use a remote control. However there is only one US company which seems to produce CIR receiver/transmitters

these are specifically for Intel MoBos - note that this is MoBos produced by Intel, not just having an Intel chipset like my AsRock Z68 Extreme4 Series3.

This has a 7 pin connector and the AsRock only has 4 pins. There is talk of adapting this at

the apparent requirement to pick up an additional power pin from an adjacent USB header and connect to the Vcc pin is puzzling me. suggest that Vcc is a positive power supply pin. However there is already a +5V pin and the USB power pin would also supply +5V. The pin is labelled +5VSB (+ 5 V Standby) which suggests that it may have something to do with switching in and out of standby but both AsRock connectors only have this power and ground, plus RX and TZ, sp presumably yhis is where the power comes from? Again only 3 pins are used in the AVSForum solution below.

There is a supposed DIY solution described at

uses a photo diode from Farnell is no longer produced. The pinout of the Front Panel CIR Receiver seems to match the pinout of the Intest device but (although there is no connection to the Vcc pin) there are additional components added presumably to fit the photo diode to the levels required on the CIR connector.

Further confusion (at least to me) comes from the fact that the IR and CIR headers seem to be very much the same on the AsRock board.

CIR IR

----- -----

+5VSB +5VSB TX TX RX RX GND GND Dummy

The CIR is a 4 pin single strip, and the IR is a 6 pin double strip with one hole blanked.

In the AVSForum schematics for the CIR 7 pin connector there seems to be a pin for RX (CIR input) but no connection to the LED pin for TX as specified in the Inset thread, so I don't know if you would need two IR devices (such as the discontinued Farnell component) to be able to transmit as well as receive.

So all in all I seem to have two slightly conflicting sources (for example the AVSForum device doesn't seem to need an extra power pin off the USB header) with no eaxct match.

Potentially the best solution would be to get the Intest device and then map the pins to the 4 pins on my MoBo if I can resolve the power issue.

In that case I assume that the neatest solution is to get a 4 pin Molex(?) connector to fit the mother board 4 pins, and either rewire from the 7 pin socket or get another 7 pin+blank plug and make up an adapter cable so I don't have to hack the original part about.

Why am I going to all this trouble? Well with an HTPC it is nice to be able to power up and power down via the CIR, and also control it like an audio or video player from a remote control instead of needing a keyboard and mouse at all times. Also, because the headers are on there and I would like to try and use them. I know the easy route would be to buy an external sensor and connect it to a USB port but it would be nicer to integrate the IR into the case.

Cheers

Dave R

[Johann Klammer]

> and these are specifically for Intel MoBos - note that this is MoBos

Contrary to 5V,

5VSB is still available when the computer is powered off(no.. in _standby_ ). This is necessary if you want to use the circuit for powering up.

How this is done varies. There may be solutions to use wake-on-lan headers on the mainboard, or BIOS settings to wakeup when seeing serial input or PS/2 activity, depending on what your mainboard uses for CIR.

There seems no real standard for those. While your p Consumer Infrared Module, PS2 Header: CIR / EXT_KBMS When the header is not in use, please short pin 3&5, pin 4&6, pin 7&9, and pin 8&10. Pin Signal Pin Signal 1 +5V 2 GND 3 KB_CLK 4 KB_DATA 5 EXT_KBCLK 6 EXT_KBDATA 7 MS_CLK 8 MS_DATA 9 EXT_MSCLK 10 EXT_MSDATA

This is essentialy pin headers for PS/2 Keyboard and mouse. The backpanel connectors EXT_... get disconnected by pulling the jumpers, and as a consequence cannot be used.

IMHO CIR just means: Whoever uses this has to invent something on his own.

If you are into Microcontroller hacking, You could surely come up with some circuit for your specific situation.

I once did that and it worked most of the time.

Should you really go down _that_ road, I can put some schematics and source code on the net.(another DIY solution)

Hint: Besides soldering Iron, you will likely need a parallel port for programming the chip.

Regards, JK