Texas Instruments MSP-FET430, Руководство пользователя

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Frequently Asked Questions
A-11
26) On devices equipped with a Data Transfer Controller (DTC), the
completion of a data transfer cycle will preempt a single step of a
low power mode instruction. The device will advance beyond the low
power mode instruction only after an interrupt is processed. Until an
interrupt is processed, it will appear that the single step has no effect.
A work around to this situation is to set a breakpoint on the instruction
following the low power more instruction, and then execute (GO) to this
breakpoint.
27) The transfer of data by the Data Transfer Controller (DTC) may not
stop precisely when the DTC is stopped in response to a single
step or a breakpoint. When the DTC is enabled and a single step is
performed, one or more bytes of data can be transferred. When the
DTC is enabled and configured for two-block transfer mode, the DTC
may not stop precisely on a block boundary when stopped in response
to a single step or a breakpoint.
28) The C-SPY Register window now supports an instruction cycle
length counter. The cycle counter is only active while single stepping.
The count is reset when the device is reset, or the device is run (GO).
The count can be edited (normally set to zero) at any time.
29) It’s possible to use C-SPY to get control of a running device
whose state is unknown. Simply use C-SPY to program a dummy
device, and then start the application with RELEASE JTAG ON GO
selected. Remove the JTAG connector from the dummy device and
connect to the unknown device. Select “DEBUG->BREAK” (or the
“stop” hand) to stop the unknown device. The state of the device can
then be interrogated.
30) RESET’ing a program temporarily requires a breakpoint if PROJECT-
>OPTIONS->DEBUGGER->SETUP->RUN TO is enabled. If N or more
breakpoints are set, RESET will set a virtual breakpoint and will run to
the RUN TO function. Consequently, it may require a significant
amount of time before the program “resets” (i.e., stops at the RUN
TO function). During this time the C-SPY will indicate that the program
is running, and C-SPY windows may be blank (or may not be correctly
updated).
31) RUN TO CURSOR temporarily requires a breakpoint. If N breakpoints
are set and virtual breakpoints are disabled, RUN TO CURSOR will
incorrectly use a virtual breakpoint. This results in very slow
program execution.
32) The simulator is a CPU core simulator; peripherals are not
simulated, and interrupts are statistical events.
33) On devices without data breakpoint capabilities, it’s possible to
associate with an instruction breakpoint an (arbitrarily complex)
expression that C-SPY evaluates when the breakpoint is hit. This
mechanism can be used to synthesize a data breakpoint. Refer to
the C-SPY documentation for a description of this complex breakpoint
mechanism.
34) The ROM-Monitor referenced by the C-SPY documentation applies
only to older MSP430Exxx (EPROM) based devices; it can be ignored
when using the FET and the FLASH-based MSP430F device.