Search found 9 matches

by Machdisk
Mon Jan 14, 2019 9:44 pm
Forum: Processors
Topic: USB and internal xlinks failing over time
Replies: 15
Views: 387

Re: USB and internal xlinks failing over time

There were reasons at the time I did it that way although they have since become irrelevant (beyond the fact that this part does not have a power good output and is both very affordable and I've used it happily in the past) but I don't see why it would cause an issue? (Unless 3V3 fails to come up bu...
by Machdisk
Mon Jan 14, 2019 8:16 pm
Forum: Processors
Topic: USB and internal xlinks failing over time
Replies: 15
Views: 387

Re: USB and internal xlinks failing over time

Easy enough, its just a couple of switch regulators like the attached. Adjusting R89, R94 lets me set any delay I want. Any particular value that you think is optimal?
by Machdisk
Mon Jan 14, 2019 10:13 am
Forum: Processors
Topic: USB and internal xlinks failing over time
Replies: 15
Views: 387

Re: USB and internal xlinks failing over time

Does anyone have a spec for acceptable amounts of ripple on the PLL_AVDD line? I know the cap is meant to be mounted close to it but it doesn't define what that is. Mine is within about 10mm but I've noticed there is a little more ripple on the back of the via from the pin than at the cap.
by Machdisk
Mon Jan 14, 2019 7:54 am
Forum: Processors
Topic: USB and internal xlinks failing over time
Replies: 15
Views: 387

Re: USB and internal xlinks failing over time

It's an off the shelf 24V power supply with a bunch of DC-DC regulators creating all the downstream rails. 24V ramps up when switched on over 40ms. No spikes get onto the 1V or 3v3 rails. 3V3 ramps up over 4ms then 1V ramp 10ms later over about a 4ms ramp as well. Reset comes up about a full second ...
by Machdisk
Fri Jan 11, 2019 8:04 pm
Forum: Processors
Topic: USB and internal xlinks failing over time
Replies: 15
Views: 387

Re: USB and internal xlinks failing over time

Thanks for responding guys. In order: PLL supply filter is using the 4r7. Both power sequencing targets are met. Excessive amounts of available current on every rail are available. (4Amps). Reset is pretty much per the reference design: An NC7WZ07 that resets on a xsys_reset or a power good reset. T...
by Machdisk
Fri Jan 11, 2019 1:24 am
Forum: Processors
Topic: USB and internal xlinks failing over time
Replies: 15
Views: 387

USB and internal xlinks failing over time

Hello All, I'm struggling a bit with a multichannel audio design implemented on an XU224-512-FB374. This is my first XMOS design I've done personally. It's an odd one and I've been digging around for ages trying to diagnose it. The issue goes like this. 1) Build up a new prototype. Check all power r...
by Machdisk
Wed Aug 01, 2018 5:01 pm
Forum: Development Tools and Programming
Topic: Sudden issue programming or flashing
Replies: 8
Views: 2321

Re: Sudden issue programming or flashing

As to using XRUN, I assume you mean over USB and this board doesn't have a separate USB port unfortunately. It's the XTAG port or bust and I can't really let it be bust. The Xtime IDE still detects the target via the xtag but then can't do anything except for resetting the board. It's got me a bit b...
by Machdisk
Wed Aug 01, 2018 4:51 pm
Forum: Development Tools and Programming
Topic: Sudden issue programming or flashing
Replies: 8
Views: 2321

Re: Sudden issue programming or flashing

Definitely not the XTAG that is at fault actually, It still works on another board and a second XTAG doesn't work on the first board.
by Machdisk
Wed Aug 01, 2018 11:25 am
Forum: Development Tools and Programming
Topic: Sudden issue programming or flashing
Replies: 8
Views: 2321

Sudden issue programming or flashing

Hello All, I'm working on a custom board based on the XU224. I have been flashing/running programs happily from xtime composer with the xtag3 programmer what must have been hundreds of times when suddenly (without changing any hardware or code) I can no longer do either and I get this error: xrun: F...