Texas Instruments MSP-FET430 manual Using C-SPY, Breakpoint Types, Using Breakpoints

Development Flow

2.3 Using C-SPY

Refer to Appendix C for a description of FET-specific menus within C-SPY.

2.3.1Breakpoint Types

The C-SPY breakpoint mechanism makes use of a limited number of on-chip debugging resources (specifically, N breakpoint registers, refer to Table 2-1 below). When N or fewer breakpoints are set, the application runs at full device speed (or “Realtime”). When greater than N breakpoints are set and Use Virtual Breakpoints is enabled (FET DEBUGGER->SETUP->USE VIRTUAL BREAKPOINTS), the application runs under the control of the host PC; the system operates at a much slower speed, but offers unlimited software breakpoint (or “Non-Realtime”). During Non-Realtime mode, the PC effectively repeatedly single steps the device and interrogates the device after each operation to determine if a breakpoint has been hit.

Both (code) address and data (value) breakpoints are supported. Data breakpoints and range breakpoints each require two address breakpoints.

Table 2-1. Number of device breakpoints, and other emulation features.

Device	Breakpoints	Range	Clock	State	Trace
	(N)	Breakpoints	Control	Sequencer	Buffer
MSP430F11x1	2
MSP430F11x2	2
MSP430F12x	2
MSP430F12x2	2
MSP430F13x	3	X
MSP430F14x	3	X
MSP430F15x	8	X	X	X	X
MSP430F16x	8	X	X	X	X
MSP430F161x	8	X	X	X	X
MSP430F41x	2		X
MSP430F42x	2		X
MSP430F43x	8	X	X	X	X
MSP430F44x	8	X	X	X	X
MSP430FE42x	2		X
MSP430FG43x	2		X
MSP430FW42x	2		X

2.3.2Using Breakpoints

If C-SPY is started with greater than N breakpoints set and virtual breakpoints are disabled, a message will be output that informs the user that only N (Realtime) breakpoints are enabled (and one or more breakpoints are disabled). Note that the workbench permits any number of breakpoints to be set, regardless of the USE VIRTUAL BREAKPOINTS setting of C-SPY. If virtual breakpoints are disabled, a maximum of N breakpoints can be set within C- SPY.

RESET’ing a program temporarily requires a breakpoint if PROJECT- >OPTIONS->DEBUGGER->SETUP->RUN TO is enabled. Refer to FAQ, Debugging #30).

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