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Can the RCX connect to a laptop with a IR reciver on it? I want to program my RCX on my computer, But i have no db9 (Lego RCX connecter for 1.0 tower) seriel connecter nor a converter.

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There are converters available for serial to USB, I had to buy one last month for some networking kit. – Zhaph - Ben Duguid Feb 9 '12 at 11:42
And example of one such converter can be seen here: – Zhaph - Ben Duguid Feb 9 '12 at 12:22
I've been trying to get an RCX to talk to a serial IR tower using a usb/serial converter - without success. More here:… – Andy Johnson Feb 9 '12 at 16:17
thanks guys, that helps a lot! – zaabtoop Feb 9 '12 at 18:28
up vote 3 down vote accepted

As far as I remember, the protocol LEGO uses is incompatible with standard IR protocols used in PCs (not even the same frequency, if I remember correctly).

The NQC FAQ has some more explanation on why it's not possible, but their short explanation says it all:

Quite simply, these protocols are incompatable. (sic)

You may have some success using a NXT brick and the IRLink sensor, but I'm not sure how far you can go (for example, I'm not even sure you can upload a firmware, and you need to be able to do that).

The easiest way is to stick with the IR tower, and in addition of the serial-to-usb converter mentionned by Zhaph, don't forget there's a USB version of the IR tower available on Bricklink (see here or here).

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