XTAG2 interface

[SpacedCowboy]

Are the link ports (pins 6{X0D4}, 10{X0D5}, 14{X0D6} and 18{X0D7}) required for the programming/debugging interface ?

I'm using the XC-3 schematics as a reference for a new design and have just come across those links being used, having already routed out a fair proportion of the design on the PCB [sigh], including dedicating those pins elsewhere. I'd rather not have to re-do everything if its not necessary - I'm not using links at all in this design.

Cheers
Simon

[sethu_jangala]

Hi,
The FAQs section ihe XMOS website answers your question.

Are all pins of the XSYS connector necessary for XTAG during production?

The minimum requirement for XTAG is to connect the following 7 signals: RST_N, TRST_N, TMS, TCK, TDI, TDO, GND The xConnect Links and UART connections are really for advanced debug, so they can be left off of production boards.

For advanced debugging like using xScopes links have to be used.

-Sethu.

[XMatt]

Also if your board design is using a G series device the links are not compatible with the L series device on the XTAG2 so you may as well not connect them.

[SpacedCowboy]

Excellent, thanks for the info ;)

Simon