As an example, in one architecture of the C6000 family, all instructions are 32 bits long, and bit 28 is reserved to indicate a software breakpoint, so all instructions in that instruction set have bit 28 as a zero. Some devices reserve a specified bit in their opcode definition that indicates a Software breakpoint. But how is that done? There are actually a 2 different implementations. The simplest way to figure out how many a device has is to connect to it in CCS and keep setting HWBPs until you get an error message that there are none available.Īs mentioned, a Software Breakpoint is implemented in software. The number of HWBPs available differ from architecture to architecture, but in most cases there are only 2-8 available. The disadvantage of the HWBP is, because they are implemented in hardware, there are a limited number available. It's just matching an address on the PAB and halting the CPU when it finds one. Hardware Breakpoints can be used regardless of whether the code being executed is in RAM or ROM, because to the hardware breakpoint logic, there is no difference. When we discuss software breakpoints, we will find that they are only usable in Volatile memory. This might make more sense after Software breakpoints are discussed. The advantage of using a hardware breakpoint is that it can be used in any type of memory. When the code is executing, and all of the bits in the address on the program address bus match the bits programmed into the comparators, the Hardware breakpoint logic generates a signal to the CPU to Halt.

These comparators are programmed with a specific address value.

You can think of a hardware breakpoint as a set of programmable comparators that are connected to the program address bus.

Memory break points : These are special software breakpoints that can be set on the memory olly has of a processĪ Hardware Breakpoint is really implemented by special logic that is integrated into the device. Have limitation to set maximum of 4 memory break points. Hardware break points : These breakpoints can be used to break when any instruction try to attept to read, write or execute a specific address, Whenever the thread attempts to execute a piece of code that you set a break point on.Ģ.

Software break points : by pressing F2 : They cause the processor to halt in the bedugger

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