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JTAG connections for a TS201 multiprocessor design

Question asked by Rohit on Jan 21, 2010
Latest reply on Feb 1, 2010 by BobK

I am designing a board with four TigerSHARCs (ADSP-TS201). JTAG port of these DSPs will be
connected in the daisy-chaining fashion. In EE-68 application note, it is
stated that the traces between the JTAG header and the DSP should be routed
as a group using equal length. I have two related doubts:

1) I understand that all the JTAG signals for a DSP should be routed with
an equal length e.g., L0 for DSP0, L1 for DSP1, L2 for DSP2 and so-on. My
doubt is whether these lengths should be equalized across all DSPs i.e.,
Should I make sure that L0 = L1 = L2 or L0 can be different from L1 and L2

2) In daisy-chaining mode, TDO of DSP0 will be connected to TDI of DSP1.
How should I calculate the length of TDI signal for DSP1 in order to ensure
that other JTAG signals are routed with same length as of TDI signal?

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