hi i need to use 4pins etm trace on stm32f429 but i have this problems:
1- i cant trace when core clock is more than 100 mhz?
2-if i chose core clock to 100 mhz and run program for a few seconde( like 3s) i have a large value of times on performance analayzer windows. (like 4075.25s on init function) !!!?
i use ulink pro and mdk arm 5 thanks best regards
>1- i cant trace when core clock is more than 100 mhz?
The signal integrity of the 4 bit trace port is critical at higher frequencies. Please check the following things: - are the pins of the trace-port configured in 'fast' mode with a high slew rate? - the max. bandwidth of port pins used as trace-port is limited on some devices. ETM trace with a core-clock higher than 170 MHz are hard to reach in practice. - do your PCB traces have the same length for all trace-port signals? If not, you may compensate the signal delay in the ULINKpro setup dialog (see below). The PCB traces of the trace-port signals must not have dead-ends which would cause signal reflections.
www.keil.com/.../ulinkpro_ctx_trace.htm http://www.keil.com/support/man/docs/ulinkpro/ulinkpro_tr_port.htm
>2-if i chose core clock to 100 mhz and run program for a few seconde( like 3s) I >have a large value of times on performance analayzer windows. (like 4075.25s on >init function) !!!?
This is most likely the result of corrupted trace data. Please also make sure that you selected the correct 'Core Clock' in the ULINKpro settings. See: www.keil.com/.../ulinkpro_ctx_trace.htm www.keil.com/.../ulinkpro_tr_general.htm