I have a custom board using an xs1 L16A-128-QF124 connected to a U8A-64-FB96 part, but it won't boot with both parts in the JTag chain. If I remove the U8A part from the chain, then the board will boot and run code using an XTag2 and the xrun --io <executable.xe> command.
With just the L16 part in the JTag chain, then xrun -l gives the following result:
Code: Select all
0 XMOS XTAG-2 iFQVO9dv L[0..1]
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0 XMOS XTAG-2 iFQVO9dv ??G[1]->L[2]
The L16 part has the X1LA xConnect link connected to the U8 parts X0LB with the expectation that once we have the board functioning the L16 part will boot its first node from SPI, and its second node and the U part from a link.
Whenever I try running a simple program, such as a one line print 'hello world' the error message is
.xrun: First stage multi-node boot failed, please check XN file and Xmos link connectivity
My hardware designer has been over the board and cannot find an issue as is frustrated as it appears to be working as intended, other than it won't boot. The various resets and JTag data is appearing at the XSYS header, so the JTag chain appears correct. There is however no sign of any activity on any of the xCONNECT links. This is happening on three separate boards with identical behaviour so it feels like a hardware fault, but is tricky to understand. My previous experience is only with the G4 part, and this is my first multichip board, so am not sure where the fault may be.
Has anyone successfully chained a U8A part from an L16 part (particularly from the second node of the L16 part)? I have seen posts about the Multi function audio reference design, which I believe uses the U8A part, chaining to a sliceKIT L16, but that is the other way round (by necessity as the MFA board doesn't itself have a chain connector).
thanks,
Philip
p.s. I am using the 13.0.2 version of the tools in case that is relevant.