clemens fischer wrote: >>Tom Walsh: >> >> > > > >>Has anyone experienced this? Is the wiring of multiple JTAG ports as >>I described? Do I, or should I, consider using the RTCK signal? >> >> > >isn't the RTCK signal *required* on ARM7TDMI-S cores? > > > No. Only if you run adaptive clocking do you need the RTCK signal. But, if you run at a fixed clocking rate you don't need it. I do think that this may be something I should consider, using adaptive clocking? My problem is that I have the TCK set to the slowest possible setting and I have occassional problems synchronizing. When the problem occurs, it can take 10 or more attempts to synchronize, usually 2..4 attempts. Something else I need to try, again, is terminating the signals at the far end of the chain. I finally did get an email reply from Ultimate Solutions (U.S. distributor for Abatron) about the daisy chain wiring. The wiring is correct: all signals are parallel with the exception of the obvious, TDI + TDO signals. I can appreciate that since I didn't spend $4K for thier ARM development package, or spend $800 for the telephone support. They seem to be slow at paying attention to email support. :( A nice product, but the support is not what I expected for the price. TomW -- Tom Walsh - WN3L - Embedded Systems Consultant http://openhardware.net, http://cyberiansoftware.com "Windows? No thanks, I have work to do..." ----------------------------------------------------
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Re: [lpc2000] Daisy chain JTAGs
2006-03-30 by Tom Walsh
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