Application Debug; Software Debuggers - Fujitsu DevKit16 User Manual

Application Debug

Overview of debug tools for DevKit16 and their features
T
he application could be debugged on DevKit16 by using five basic
approaches. High end debugging requires FUJITSU emulator and CPU
personality board with socket. Another way – low end - is simulation;
Softune Workbench provides MCU instruction simulator, but it doesn't
simulate MCU peripherals in current version. It is very useful to simulate
algorithms. Very experienced developers often use technique of their own
monitoring of running program behavior using character oriented (display)
device. This approach is also supported by DevKit16 and optional VGA graphic
card, which allows connect standard VGA display to DevKit16 and provides
fast buffered access (much faster than serial line). But inside this chapter we'll
concentrate to so called „software debugging techniques" which are supported
by both Softune Workbench and Processor Expert
S O F T W A R E D E B U G G E R S
Software debuggers provide good ratio functionality/cost. The target system is
equipped with small debug kernel, which provides back-end for PC Debugger –
front-end. CPU software interrupts are used for breakpoints, stepping functions.
To realize this function, user code must be located in RAM type memory. 16LX
MCUs provides „ROM Correction Modules" peripheral, which could be used
for two hardware breakpoints. Unfortunately this is not enough to realize usual
debug functions and more, this solution works for internal memory only.
The simplest kernels are „live" only when user program is stopped, so there is
no activity during application runtime. The better solution provides ability to
monitor/modify selected variables on demand even in application runtime. This
feature significantly reduces debug effort, because for instance PID regulator
could be tuned during runtime. This kind of interface is usually needed for
distributed control and visualization systems.
Advantage of software debuggers is that they could be adapted for your own
microprocessor system.
(TM)
environments.
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