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Altera_Forum
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18 years ago

JTAG configuration protocol specification

Hello, We're in the process of debugging a JTAG configuration problem (Quartus doesn't recognize the chain that consists of a single CycII device). We try to look at the TDI, TMS, TCK, TDO line...
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Altera_Forum
Icon for Honored Contributor rankHonored Contributor
18 years ago

From my personal experience I know that the first steps are:

- 6 TCK cycles with TMS set to 1 to reset the TAP controller

- TMS sequence 0100 to move to shidt DR

- more than 100 TCK cycles to read the reset value of DR

the JTAG ID code of the device should come out of TDO on the

first 32 clock cycles

is that enough for you?