February 2014
32
E
XHIBITION
H
IGHLIGHTS
Practical experience shows that highly com-
plex systems with more than one core as well
as with powerful peripherals only become con-
trollable with new trace technologies. The well
established Universal Emulation Configurator
from PLS is the right tool to deal with this on-
chip trace logic. Embedded World 2014 will
also show emulation devices from Freecale
and STMicroelectronics.
On-chip trace has been established as the state-
of-the-art technology for debugging and com-
prehensive system analysis. It is commonly
used for testing and performance measurements.
Except for a few, most microcontroller archi-
tectures are available with on-chip trace and
all major debug tool vendors promote their
support for it. In general, the term on-chip
trace means the recording of instruction exe-
cution – known as instruction trace – and the
recording of data transfers between cores and
memories and on the system busses – known
as data trace. To meet customers’ requirements
of global system observability, major silicon
vendors have extended their trace solutions
and added signal trace for peripherals.
Last year Infineon introduced with the Aurix
family powerful new automotive microcon-
trollers onto the market.With the combination
of three TriCore 1.6 CPUs, a lockstep mecha-
nism and an access permission system, Aurix
is ready for ambitious powertrain applications
demanding high performance and sophisticated
security features. A wide range of peripherals
perfectly matches the needs of present car
drives including hybrid and electrical vehicles.
As a specialty, Infineon has licensed the Generic
Timer Module (GTM) from Bosch and inte-
grated it into the controller family. The GTM
allows realization of flexible and complex
timer-controlled algorithms as well as efficient
and parallel signal processing. Besides complex
and optimized data paths inside the GTM, the
module itself is comparable to a multi-core
processor. A couple of RISC-like cores inside
the GTM allows programming of parallel chan-
nel programs. However, in addition to that,
the GTM consists of a lot of modules for gen-
erating, filtering and transmitting signals.
Debugging and system analysis of such complex
and powerful microcontrollers require sophis-
ticated on-chip debug support and trace. Hence-
forth, for run-time analysis not only program
and data trace from cores and busses are needed,
but also a bunch of single-bit and multi-bit
signals from peripherals and the GTM must
be taken into account. Therefore, for Infineon
the challenge was to extend its trace solution
to meet these requirements. However, with up
to a few hundred single-bit signals needed to
be part of the trace output, the trace hardware
located on the die, and not least the trace port,
quickly reach their limits. The only solution is
to limit the amount of signals coming out
from the peripherals and the GTM according
to the actual debug use-case.
For this purpose Infineon has extended the
On-Chip Debug System (OCDS) of the Aurix
MCUs with a trigger switch (figure 1). It allows
to transfer selected bunches of signals from
peripherals as well as the GTM to different
sinks of the debug system. One of those sinks
is the Multi-Core Debug Solution (MCDS) –
the trace system of the present Infineon mi-
crocontrollers. The vast amount of accrued
data is preselected by means of multiplexer
cascades. Typically, sets of 16- or 32-bit signals
form so called trigger sets, while the containing
signals are the fix for each trigger set. Selected
trigger sets are then transferred by OCDS trig-
Trace extended to make
the peripherals visible
By Jens Braunes,
PLS
Code and data trace allow
only a limited view of the
real-time behavior of current
embedded systems. Apart
from debug information com-
ing from system busses and
cores, there are often special
signals inside the peripherals
which may be important for
debugging, test and system
analysis, and are available by
extended signal trace.
Figure 1. Trigger switch for observation of
peripherals
