Yes, the entropy of the data is much much lower, however this is the rate at which it is "coming out". It has to be decoded by the FPGA and filtered, probably even compressed somewhat as most of it are only synchronizing sequences, and empty frames, and repeating sequences like (Memory at address 0xDEADBEEF has been written to)
I think that a high speed(?) 480Mbps connection is more than enough for the useful data. Probably a 100Mbps ethernet interface should suffice as well. I can't tell a close approximation of the needed bandwidth as I never looked into the ETM block, which generates the bulk of it, because with the slower interface (1MBps) it is impossible to capture the traffic (overflow occurs very fast). The ETM is responsible for an instruction-level trace, and makes it possible to see what the processor is executing at an instruction level. As you can imagine that is a lot of data. The other two blocks - which I use, the ITM, DWT - generate much lower amount of data, and can be confortable sent over a 10Mbps connection. I am currently using a 1Mbps bandwith UART transport, and it does generate overflows, but it is rather rare. I'll ask the guys who have looked into the ETM how much data do they think it will generate in a real-world scenario. Regards, Ákos Vandra Regards, Ákos Vandra On 14 June 2012 00:24, Peter Stuge <[email protected]> wrote: > Akos Vandra wrote: >> plan ahead and design a hardware that will be able to capture the >> trace traffic > > How much traffic do you think is needed to be useful? > > 800Mbps sustained gets difficult to manage really quickly. > > If there's no alternative to streaming then I think the 800Mbps needs > to be encoded into higher level information somehow, so that only > smaller amounts of data goes through. > > > //Peter > > ------------------------------------------------------------------------------ > Live Security Virtual Conference > Exclusive live event will cover all the ways today's security and > threat landscape has changed and how IT managers can respond. Discussions > will include endpoint security, mobile security and the latest in malware > threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ > _______________________________________________ > OpenOCD-devel mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/openocd-devel ------------------------------------------------------------------------------ Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ _______________________________________________ OpenOCD-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/openocd-devel
