XTAG4 and link pins Topic is solved

[SpacedCowboy]

This is probably answered somewhere but I've spent some time looking and I can't see it actually spelt out anywhere, so...

Do you actually need to use the xlink0 {rx0, rx1, tx0, tx1} pins on a target board, in order for the Xscope functionality to work, or will any 2-bit link work ? Everyone seems to use XL0 which makes me think it probably does need to be that specific link but it'd be nice to use xlink2 because (on the FB265 package at least) that's out of the way in the higher bits of the 32-bit port on tile 1.

[xhuw]

Hey the links are configured in the XN file. You should be able to change "Link" in the "LinkEndpoint" for node 0 in your xn file.

link to the equivalent line that would need changing: https://github.com/xmos/lib_board_suppo ... -mc.xn#L82

docs: https://www.xmos.com/documentation/XM-0 ... nkendpoint

edit: I haven't tried this so it could be wrong... just a suggestion

[Joe]

You can use any link for xscope, nothing special about link 0 in that respect.

[SpacedCowboy]

Thanks, both :)

[SpacedCowboy]

One small thing - I think there's a typo in the datasheet in appendix F, in F.4, it's talking about the pins for link 0, which it says are

XL01 out (X0D19)
XL00 out (X0D18)
XL00 in (X0D17)
XL01 n (X0D16)

These all ought to be X1Dxx I think - the XOD pins are in fact link 4.

Also, it doesn't say what to do with the DEBUG_N pin - in the xcore.ai evaluation kit schematic it seems to be left floating, is that correct ?