Search found 395 matches

by rp181
Thu Jan 01, 2015 10:05 pm
Forum: Development Tools and Programming
Topic: Optimizing ADC Read
Replies: 11
Views: 11635

Re: Optimizing ADC Read

The hardware needs a lot of IO, so unfortunately this was the only possible way to fit everything. I did actually try the sequential mode earlier, but the benefit was only slight (most of the time is from the ADC conversion). I may try that again, though this is fast enough as-is! I'm going to go ah...
by rp181
Thu Jan 01, 2015 7:51 pm
Forum: Development Tools and Programming
Topic: Optimizing ADC Read
Replies: 11
Views: 11635

Re: Optimizing ADC Read

Converting everything to unsigned gave a boost of a couple kHz (didn't measure the impact of changing the shifts). I didn't really find much information on outshr and inshr, so not sure if that's applicable. Previously, the operation was as follows: - Read 2 adc channels - Compute stuff with adc val...
by rp181
Wed Dec 31, 2014 11:54 pm
Forum: Development Tools and Programming
Topic: Optimizing ADC Read
Replies: 11
Views: 11635

Re: Optimizing ADC Read

Thanks for all of the advice! I implemented most of it, and my in-application speed went from 30 kHz to 60kHz!
by rp181
Wed Dec 31, 2014 7:26 pm
Forum: Development Tools and Programming
Topic: Optimizing ADC Read
Replies: 11
Views: 11635

Re: Optimizing ADC Read

Ok, so i timed it again and I am getting 1360ns. Using a scope and a DAC output, 1500 ns (makes sense because the DAC takes a bit of time to write to). I don't have a great scope/LA right now, so making do with a 20 MHz scope. I'm not sure where the discrepancy between the timing analyzer (520ns) an...
by rp181
Wed Dec 31, 2014 7:00 pm
Forum: Development Tools and Programming
Topic: Optimizing ADC Read
Replies: 11
Views: 11635

Re: Optimizing ADC Read

Thanks for the feedback! mon2: The clk pin is actually buffered to 32 bits (and clocked). 14 pulses equates to 28 pin states, so there's not many wasted cycles. The 25.5 MHz is the frequency of the square wave (rising edge to rising edge) which is two states, so a pin transition rate of 50 MHz equat...
by rp181
Tue Dec 30, 2014 7:12 pm
Forum: Development Tools and Programming
Topic: Optimizing ADC Read
Replies: 11
Views: 11635

Optimizing ADC Read

Hi guys, In my current project, it's gotten to the point of reading 2x parallel ADCs (AD7938) is the bottleneck in the operating speed. I'm posting here to see if anyone has ideas to speed up reading. The ADC is capable of 1.5 MSPS, but i'm achieving a read rate of about half that. Physically speaki...
by rp181
Fri Nov 14, 2014 6:52 pm
Forum: Development Tools and Programming
Topic: error in multi-node boot
Replies: 4
Views: 6163

Re: error in multi-node boot

Oops- I've been testing with 4,4 - same issue. I do not have the mode pins configured to boot from JTAG, could this be the issue causing this? I was pretty sure it is a software issue because a) it was working for a period of time and b) I have to identical systems- both were working and now both ar...
by rp181
Fri Nov 14, 2014 3:40 am
Forum: Development Tools and Programming
Topic: error in multi-node boot
Replies: 4
Views: 6163

error in multi-node boot

I have a chain of 9 L1's. I had the system working- I was printing data off of some node. But now when i try to execute I get an error: C:\Users\User\AppData\Local\Temp/.xrun6188-RPNERR1I/xeload_auto.gdb:5: Error in sourced command file: First stage multi-node boot failed, please check XN file and X...
by rp181
Fri Apr 11, 2014 2:49 pm
Forum: Latest news
Topic: WINNER ANNOUNCED : Win a New xCORE Analog SliceKIT!
Replies: 143
Views: 211514

Re: COMPETITION TIME : Win a New xCORE Analog SliceKIT!

Develop a cheap hemoglobin monitor for pregnant women in India.
by rp181
Sat Dec 21, 2013 4:12 am
Forum: XMOS Devices
Topic: 3rd Degree Hypercube
Replies: 3
Views: 3774

3rd Degree Hypercube

I have an upcoming project in which I'll need 8 processors connected together. I came across the supported topology, which includes a cube of processors. Has anyone does this? How does booting the other processors work? Does it matter which one is the "master" node (i.e. the one the xtag c...