I was thinking about this modification between 5K and 100K... Tell me if I am wrong: I think you have measured your ultrapitch after having desoldered it; Then, you know it is a 100K, but it has his tolerance, so maybe you measured 102K for example. So, in order to have the good values of resistances to put in your programm, you have made the calculation with 102K and not 100K. It means that for every new device you will make, you will have to adapt your programm after measuring the value of the ultrapitch, even if you just do it with 100K's (once you will measure 98K, another ultrapitch will be 99, 98.5, 101.5, etc). In other words, for each new midi system to build, you will have to modify the programm...Isn't it?