Many chips come with on-board debugging accessible via JTAG that lets you do most of what you'd do with ICE in the good old days. Another option I've seen is t

Many chips come with on-board debugging accessible via JTAG that lets you do most of what you'd do with ICE in the good old days. Another option I've seen is to simulate/emulate at lower speeds with FPGAs. I also had a lot of fun debugging electronics. My favorite story is spending more than a month debugging a TI DSP based board that I designed that wouldn't boot properly. It turned out that some of the ground pins (it had many) were left unconnected because the guy that did the PCB layout (not me, I did do layout for many of my designs but not this one), didn't notice a tiny segment that needed to be wired from the pin to the ground plane. An important lesson I learned from debugging hardware is that you have to persevere, I learnt this from a very experienced EE I worked with, all problems can be found with enough perseverance. Kids these days (lol) give up too soon...