Thursday, April 30, 2015

Rev C bring up

I built the first rev C of Titan earlier this week, and I've been working to bring up the board. This has been the cleanest build yet. It did take about five hours to build by hand, but my process is getting better with each build.

So far I've confirmed that all of the power rails are operational, the on-board USB programming circuit works, and the FPGA can be programmed. The LED counter didn't run when I loaded titan_wiggle, so I'll need to debug a little tonight.

Figure 1. First Rev C.

1 comment:

John Sloan said...

It turns out the PERSTn was working correctly, just not as I expected. On most mother boards PERSTn is asserted for 100-200ms just after power is applied, then de-asserted.

On the Hummingboard-i2ex that I'm using, PERSTn is asserted at power-on and only de-asserted when an OS loads that includes support for PCIe (ie. Debian Jessie).