Remote Controller Micro Pin Mapping

Thread Starter

iceburnhex

Joined Jun 14, 2022
19
Good afternoon,

As the title suggests, I could use some help on how to best map out a microcontroller on a remote controller (handwand to a chair).
Reason is I would like to eventually reprogram it to do different things, but that's for later. I currently don't know where to being exactly with how to map out which Switches (there are 9 push button switches) along with LEDs to each. These are what I need to figure out so I can reprogram the micro to control a function based on which switches are pressed.

My issue is, taking a multimeter, I cannot trace any direct path to the micro. Everything is either behind a diode or resistor, making continuity checks difficult. I've located the "ground" side of each, and verified them to ground. They are all tied together. The other side goes to a diode, then disappears somewhere behind the circuit board on the other side, or potentially just a spot I haven't be able to find direct path continuity to yet.

Is there a better method or way to do this? I was thinking they might be charliplexed, and if so, how would I go about mapping/drawing out where everything goes with no schematic, and no idea what pins do what on the current micro. Any help or tips, good resources for this specific type of problem would be greatly appreciated, thanks!
 

Thread Starter

iceburnhex

Joined Jun 14, 2022
19
What is the number on the microcontroller, then look up the datasheet.
Thats part of the issue, its unlisted as of right now.
There are some header ports, and I have a guess as to which micro it is, but it doesn't tell me how it was previously programmed, and which pins are used for which. If I flash it, it'd be lots of trial and error to see which pins the switches would be on regardless.
 

Papabravo

Joined Feb 24, 2006
21,324
Thats part of the issue, its unlisted as of right now.
There are some header ports, and I have a guess as to which micro it is, but it doesn't tell me how it was previously programmed, and which pins are used for which. If I flash it, it'd be lots of trial and error to see which pins the switches would be on regardless.
What does in mean for it to be unlisted? Does that mean you no idea who makes it and what it might be capable of? Does it mean you are going to try to divine the purpose of each pin from an unidentified part on a PC board. If that is the case, I predict you will have zero chances of success after literally years of fruitless effort.

Start with a datasheet for a known part that you can acquire at reasonable cost, design a PCB from one of the express PCB houses, and knock yourself out writing the firmware. I promise you will get there faster and with more satisfaction this way. Trust me on this.
 

Thread Starter

iceburnhex

Joined Jun 14, 2022
19
What does in mean for it to be unlisted? Does that mean you no idea who makes it and what it might be capable of? Does it mean you are going to try to divine the purpose of each pin from an unidentified part on a PC board. If that is the case, I predict you will have zero chances of success after literally years of fruitless effort.

Start with a datasheet for a known part that you can acquire at reasonable cost, design a PCB from one of the express PCB houses, and knock yourself out writing the firmware. I promise you will get there faster and with more satisfaction this way. Trust me on this.
The micro is a 48 pin chip with no markings on it. No idea who makes it. I know it sends out a binary code at 115200 baudrate that I've be able to decode. I know it uses 9 switches, 13 LEDs and a faceplate LEDs (haven't counted those yet). No bluetooth or wifi capabilities (so far as I know on the board).
Even if I had the data sheet, those pins are very configurable. Hence why I'm asking for a method of tracing the micro to the switches, or a method that actually would allow me to more easily figure out which pins those switches are on.
If there isn't a good way to map it out with a clever trick or something, and you just have to go thru every component, then that's fine. There is a reason why I'm using this remote and not just building one specifically.
 

Papabravo

Joined Feb 24, 2006
21,324
The micro is a 48 pin chip with no markings on it. No idea who makes it. I know it sends out a binary code at 115200 baudrate that I've be able to decode. I know it uses 9 switches, 13 LEDs and a faceplate LEDs (haven't counted those yet). No bluetooth or wifi capabilities (so far as I know on the board).
Even if I had the data sheet, those pins are very configurable. Hence why I'm asking for a method of tracing the micro to the switches, or a method that actually would allow me to more easily figure out which pins those switches are on.
If there isn't a good way to map it out with a clever trick or something, and you just have to go thru every component, then that's fine. There is a reason why I'm using this remote and not just building one specifically.
There is literally nothing that will be of much help to you. The board that the PC board that the processor is on is likely a multi-layer board which makes tracing the connections next to impossible, because the connection may be on inner layers. Just give up this hopeless effort and move on. Switches and lEDs are not rocket science. You are manifestly wasting your time approaching this problem in this way.
 

Dodgydave

Joined Jun 22, 2012
11,375
Thats part of the issue, its unlisted as of right now.
There are some header ports, and I have a guess as to which micro it is, but it doesn't tell me how it was previously programmed, and which pins are used for which. If I flash it, it'd be lots of trial and error to see which pins the switches would be on regardless.
Have you got a picture of it?
 
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