Hardware debuggers and Neutrino

The major constraint of using pdebug is that the kernel must already be running on the target. In other words, you can't use pdebug until the IPL and startup have successfully started the kernel.

However, the IPL and startup program run with the CPU in physical mode, so you can use conventional hardware debuggers to debug them. This is the primary function of the JTAG debugger throughout the Neutrino software development phase. You use the hardware debugger to debug the BSP (IPL and startup), and pdebug to debug drivers and applications once the kernel is running. You can also use a hardware debugger to examine registers and view memory while the kernel and applications are running, if you know the physical addresses.

If hardware debuggers, such as SH or AMC have builtin Neutrino awareness, you can use a JTAG to debug applications. These debuggers can interpret kernel information as well as perform the necessary translation between virtual and physical memory addresses to view application data.