custom board - XCore 0 is not enabled Topic is solved

[countbadger]

I have been attempting to make my own XMOS  dev board for interest's sake but cannot seem to get the thing working. Connecting the Xtag to the board allows the JTAG tap to enumerate the board correctly  but during programming i get "xrun: Cannot load image, XCore 0 is not enabled".  
 
 
Checking power sequencing, the IO supply hits 3v3 a good 10ms before Vcore ramps up to 1v.
 
As soon as Vcore hits 0v9, the reset is pulled low for up to 10ms (have been switching the charge delay capacitor with different values).
 
The clock is running at 25MHz (0-3v3 peak).
 
MODE[0] is tied to ground, MODE[1] is tied to 3v3,MODE[2] and MOD[3] are  tied to pin 3 of the  XTAG header.
 
VPLL is sitting at 0.95v which is in the 10% range.
 
At this point i have no idea what i have missed so pointing out obvious issues will be greatly appreciated.

[infiniteimprobability]

WHat you describe sounds sensible, however clearly something isn't right yet..The error message basically means that the CPU isn't running - that can be power related or incorrect mode/not coming out of reset..so we need to identify what is not in place to stop the CPU running.

This may be handy to run through and double check:

http://www.xmos.com/support/knowledgeba ... i-get-xrun...

I couldn't read the schematic, but presumaby you can confirm sections G, H & I have been followed?

One thing worth checking is to see if it can boot from SPI flash (at least the chip waggles the SCLK pin on boot). This will identify if it is something fundamental.