AN4224 Trace support on MPC5744P for code coverage analysis

[guenter_loettrich]

Dear all,

There are no Aurora pins available on the 144 pin package of MPC5744P.

When looking at Table-1 and Figure-1 in AN4224 does that mean that tracing through JTAG TAP (without using MDO pins) is not possible with MPC5744P in LQFP144?

For instance when someone wants to do code coverage analysis then the NPC Auxiliary Port has to be used on LQFP144 - which will be slower than Aurora or move to BGA257 where the high speed trace capabilities through Aurora is available. Is my assumption right?

Thanks

br

Guenter

[guenter_loettrich · Accepted solution]

In the meantime I've got feedback from the automotive apps team, thanks to Randy Dees:

"The Nexus standard allows for multiple types of external
trace interfaces. Specifically, it allows for a parallel trace interface
(defined in all revisions of the IEEE-ISTO 5001 standard) and the high-speed
serial trace interface, that utilizes the Aurora transport mechanism (added in
the IEEE-ISTO 5001-2012 version of the standard). 

The 144 pin package does have access to a 4-bit parallel
Nexus trace interface (MDO). This does allow limited trace bandwidth for code
coverage analysis. Branch history mode may need to be selected in the tool due
to the limited bandwidth available with the 4-bit MDO parallel Nexus interface.
Branch History mode does allow the tool to determine if all branches had been
executed (taken/not taken) for code coverage. If more detailed trace
information is required, then the larger package would have to be used. For
some products, Freescale does have adapters available that allows access to the
high-speed Aurora Nexus interface by using the larger package and fitting into
the smaller package footprint. Unfortunately, this type of adapter is not
currently available for the MPC5744P. 

The trace data is never accessible via JTAG port of the
MPC5744P. That would require the trace to memory option, which is not
implemented on the MPC5744P (as shown in Table 1 of the application note). This
is also shown in Figure 1 of the application note, although this may not be
clear. In figure 1 it does not define the difference between the heavy
dark/black "bus" (JTAG control) and the heavy grey "bus' that is
the Nexus trace data.

The customer should refer to AN2614 "MPC553x,
MPC555x, and MPC556x Family Nexus Interface Connector" or AN3968
"Nexus Interface Connector for the MPC567xF and MPC5676R Families"
for recommended pin-outs of the parallel Nexus interface. For the 4-bit
parallel Nexus interface, usually, the 32-pin MICTOR connector is used,
however, the 50-pin SAMTEC may also be used if the customer uses the same tools
for devices that support the 16-bit parallel Nexus interface. (Normally, the
MICTOR is recommended for 4 to 12-bit MDO pins [AN2614 and AN3968] and the
SAMTEC 50-pin for 12 to 16-bit MDO devices [AN3968]). "