I came across star tsp100 and this reminds me of my first job. I had to work with thermal printers, then Java applets. A year later, I had to do embedded programming, then printers again. When I transferred to Manila, I had to deal with Java again. When I went back to Japan, I had to deal with different fields: embedded programming (again), Java, and C++!
After all these years of being involved in software development, I realized that I am a master none. I know a bit of many things and I want it to stop. Hopefully, I get to keep what I have been doing in my current company. And I have to convince my self to stick to it, no matter how difficult things currently are.