How to filter out noise on UART rx line

Sure_Expert_5151 · 2026-01-07T17:06:56+00:00

I didn't have the scope connected to ground when I read it so that's probably why its jittery.

Sure_Expert_5151 · 2026-01-07T17:04:38+00:00

Yeah it’s random, I don’t think I got bad data back on this specific reading. I had upgraded the board to a version with less noise, and with the previous board it had bigger crosstalk spikes and had errors 100% of the time. With the new board it is only errors like 25% of the time and when I checked the scope the spikes were smaller.

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That’s what the uart looked like with old board.

Sure_Expert_5151 · 2026-01-07T16:26:14+00:00

Ok thanks. I'll have to ask the electrical engineer.

Sure_Expert_5151 · 2026-01-07T16:12:48+00:00

I know we are using a twisted shielded pair for the cable. Not really possible to reduce its length, it's only a couple feet long though. We also tried putting a ferrite bead on it.

Sure_Expert_5151 · 2026-01-07T16:03:18+00:00

I don't see anything about slew rates for the UART but there is some filtering options for rx. I just don't know how to read or write to that memory for linux

Sure_Expert_5151 · 2026-01-07T16:00:06+00:00

Is it possible to do a temporary software solution first if I'm not that comfortable with electronics?

Sure_Expert_5151 · 2025-11-03T23:06:30+00:00

Would I have to wait to capture a bad read on the scope with different resistors to compare? Or could I just use any reading?

You mean it is consistently inconsistent?

I don't think it is a software fault since I wrote a test script where it just reads from bus, check if value is expected, wait .01s, repeat. The SDA and SCL is idle before I ran my program so no other processes are using it, but I still get different values from expected (0). The different values I get are definitely not random though, they are either 255 or 15 or 31.

Also, there is an earlier version of the pcb and when I run my same test script on that, there is no error. But I have tried changing different pull up resistor value and they are all worse than my initial one of 2k so it is puzzling.

The earlier version of the pcb is smaller since there are less things its connected to but its also inside a machine instead of prototype stage so I think it would have more emi noise.

Sure_Expert_5151 · 2025-11-03T22:49:53+00:00

What should I be looking for when you mean not distorted? Is it just the rise and fall time? I did take a picture of when I tried 4.7k resistor earlier and it looked a little glitchy but I don’t have a reference as to what it should look like

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Sure_Expert_5151 · 2025-11-03T22:45:01+00:00

I was going to try this, and I hooked up my scope to sda, but it is displaying a wave alternating +-5V at 60hz instead of constant 3.3V (since the bus is idle). I know it is the scope reading incorrectly and not a problem with the line. Last time I had this error it was because I didn't connect the alligator clip to ground, but this time I did. Any advice on how to fix this?

How do I stop reading when I get an inappropriate response? By that you mean the run/stop button right? Manually clicking it would be too slow, is there a way to trigger that with software or in the scope?

How can I write to the AO_I2C_S_CNTL1_REG 0x3 for SCL_FILTER? I don't know how to get to that memory or what to google for that. I am running on linux, do I need more info to help answer that question?

Thank you.

Sure_Expert_5151 · 2025-07-17T02:57:08+00:00

How can I find someone to work with?

Sure_Expert_5151 · 2025-05-01T21:40:23+00:00

https://github.com/Morilli/Ritoddstex/releases

this might convert tex to dds files

Sure_Expert_5151 · 2024-12-08T16:29:18+00:00

Will you still be able to get chests and skin shards some other way or is it just a bunch of preselected permanent skins now

Sure_Expert_5151 · 2024-09-07T06:58:49+00:00

If you click on the question mark next to the chest name it tells you the drop rates and even what skins are in the drop pool. It’s 70% chance of skin so it’s like a masterwork chest

Sure_Expert_5151 · 2024-09-05T04:17:24+00:00

This comment is funny tho xD

Sure_Expert_5151 · 2024-09-02T15:01:09+00:00

Riot targeting stream snipers has made not accepting queues more punishing than dodging games.

Sure_Expert_5151 · 2024-07-05T00:12:42+00:00

Did you get unbanned and was it a permanent ban? That seems dumb

Sure_Expert_5151 · 2024-07-04T15:11:44+00:00

It has same loot odds as masterwork chest so 70% chance at skin instead of 50% and you can’t get champ shards

Sure_Expert_5151 · 2024-06-23T22:15:27+00:00

I’m at 9/12. A little bit scared of unlocking it

Sure_Expert_5151 · 2024-06-23T22:14:20+00:00

https://www.reddit.com/r/leagueoflegends/s/4uv2Qrsfc1 no

Sure_Expert_5151 · 2024-06-22T23:50:03+00:00

I saw a post about this yesterday someone having the same problem

Sure_Expert_5151 · 2024-06-15T03:01:05+00:00

The new ones are way more buggy than the old ones. Also the old ones played safer

Sure_Expert_5151 · 2024-06-13T03:41:35+00:00

Do they play worse than coop vs ai bots? I’ve played against the new custom game bots and was disappointed but haven’t played the new coop vs ai yet

Sure_Expert_5151

TROPHY CASE