I had a look at the signals driving the IR transmitters on a scope. I found that when I set the MX to send mode it would send out one of two codes. One for send device and the other for send all. A code is made up of one of two pulse types. The first I call short and is a 1.6 us (microsecond) on pulse followed by an 11.7 us off pulse. The total period was 13.3 us. The second I call long and was the same 1.6 us on pulse followed by an 18 us off pulse for a total time of about 20 us.

The send all code consisted of the following sequence of short and long pulses:

SLSLSLSL followed by a 1.6 us on pulse. (9 on pulses total).

The send device code consisted of the following sequence of short and long pulses:

LSLSSLSL followed by a 1.6 us on pulse. (9 on pulses total).

These on pulses are pretty short for a remote control representing a carrier frequency of about 300 KHz. I'm sure my IR transmitter/receiver combo, which can be seen at

[Link: jdresearch.com]

has the capability to capture short pulses as it supports FIR (Fast Infra-Red) which allows it to operate up to 4 MHz. Unfortunately my motherboard doesn't have a FIR capability, just CIR (Consumer Infra Red). I don't think that the software that I am using to interface my PC to the IR device above, through the parallel port, can run fast enough to capture these short pulses accurately, if at all. I don't know if a serial port will run at a baud rate of 300 KHz.

At this point I am trying to figure out how to proceed so any suggestion would be more than welcome.

Mike

P.S. The software I am using can be found at

[Link: ziplabel.com]

I am using the WIN32DLL version, which is at

[Link: ziplabel.com]

Mike