What happens if I click go on a diagram with ADC, PWM or GPIO blocks but I didn't compile yet.

Sometimes I accidentally click “go(F5)” icon for uncompiled vsm block diagrams. Often an error will pop up and it seems that the communication between PC and DSP is dead after that. I cannot download to DSP through XDS510 USB plus emulator anymore, and I have to reset XDS510 USB (by pushing the “reset” on the DXS510 USB) to re-start the communication. Is there any way to solve this? Thanks.

Ahhh, good question

This is a feature. Let me explain. If you try to run a "source code" block diagram that you haven't yet compiled, and it has target blocks like ADC, GPIO, PWM, QEP, or CAP blocks, then VisSim will try to download a peripheral comms .out file to let you communicate to the target in real-time via the JTAG Hotlink. Probably you don't have the right JTAG communication setting in your DSP Config... for the source diagram. In this case, the CCS driver is trying to communicate with the wrong JTAG adaptor. If you set the source diagram up for your JTAG connection to the proper target, and you have configured the diagram to run in real-time, then it should run fine.
Please note that the JTAG bandwidth can vary, but 500Hz is probably the fastest it will go, so don't be surprised that you don't see clean waveforms at 300KHz like you would if you had compiled and used the monitorBuffer read/write blocks.