Trying to read the data from an ASK RF transmitter

Question

I'm trying to duplicate the operation of a simple RF remote control (for some remote power outlets). In the remote control there is an unmarked 8-pin microcontroller. I've worked out which pins are connected to the buttons on the remote and which pin sends the data to the transmitter part of the circuit (pin 6 on both, incidentally). The Tx IC is marked F115, after some googling it appears to be this one.

I'd like to read the data that is being sent from the unmarked MCU to the Tx so that I might be able to duplicate it with an arduino or ESP. Currently I'm using an ESP-01 module and some transistors to "push" the buttons. I need to determine the code that it sends to each remote outlet, I just don't know how to do that. I don't have a scope, so I'm wondering if it's possible to use the arduino itself to intercept the signal from the MCU to the Tx. I don't suppose it would be as simple as programming the arduino to receive a signal then connecting MCU pin 6 to the arduino? I'm not super well-learned in more complex stuff like this (RF and serial communication), but I'm trying to learn!

Please, if anyone knows anything that could point me in the right direction I'd be really appreciative. I don't know where to start, so I really need some input.

Answer 1

Assuming the signal is at logic levels, what you really want is a logic analyzer. These would provide you with bit value and timing information that would be easy to analyze. Given that this is only one pin, the options are greater.

There are many inexpensive logic analyzers that you can connect to a PC, and in this case maybe even a Bus Pirate would work.

However, given that this is very likely a slow signal, you have the option to build your own. There might already be open source code that does what you want, but all you really need is to sample a port pin (or use a timing capture peripheral) and send the edge changes and their timing to a computer where you can reconstruct the signal and decode at your leisure.

You could even use some software to convert your sound card into a slow oscilloscope/data capture device and then decide the signal by hand.