I have a project that I am currently working on where I am converting an old Sharp pc-4501 that was not working into modern computer, anyway long story short I have been following this guide and I made it to the final steps. For the life of me I can not get the ino file to upload to the teensy 4.1, and in the sparing times it does NON of the keys are mapped right at all. It has come to the point where I am ready to abandon this project or just pay someone to get the keyboard to work. If anyone has gone through this process I would be so glad to hear what you went through and if you have any suggestions for me. I am thinking that I could have messed up the wiring as I followed the non-solder method or that my ribbon cable could be messed up as it is really short and looks like it has been cut before.