output signal disappear, freeze?

Technical discussions around xCORE processors (e.g. General Purpose (L/G), xCORE-USB, xCORE-Analog, xCORE-XA).
Posts: 10
Joined: Fri Apr 29, 2016 7:35 am

output signal disappear, freeze?

Post by Eliwood »

Hi all,

i'm using the XE216-512-TQ128 with an 24MHz oscillator.
An ARM processor is sending data to the XMOS. This data signal contains information about the settings of the XMOS output signal (like length, number of pulses). It is 16 bit long and both tiles has this 16 bit output signal.

Now the problem:

By receiving different settings, the output signal disappears. This occurs by changing the settings for several times and the LED on my board is not flashing anymore(flashing every 10 loop cycles). So it seems that the XMOS is frozen.

So i analysed the input signal. It seems all fine. Deleting the source code for the output solved the "freeze" problem but not the output problem ;)
Furthermore, i had a 27 MHz oscillator for the XMOS and all worked fine....strange...

Has anyone an idea for this effect? (i verified the rest of the hardware and i can not find any noise on the ports...the hardware should be ok)


Respected Member
Posts: 346
Joined: Wed Jan 27, 2016 5:21 pm

Post by henk »


A bit more detail is needed; however, going by the fact that it works with a 27 Mhz oscillator but not 24 MHz, it is possible that some software on the xCORE is just too slow.

Instead of changing the oscillator, you could change the XN file to run at 600 MHz and see if that solves the problem (it will get warm, and it isn't qualified for that speed - but it will be ok for a few minutes).

If so - you need to time your software, and check that it cannot miss any data.

If faster does not resolve the problem - you will need to post more details on the protocol and the software on the xCORE side?