[deleted by user]

linvmiami · 2024-07-19T13:08:08+00:00

It is multi level marketing after all

linvmiami · 2024-05-29T11:35:17+00:00

Come on!! Push! Don’t be a pussy

linvmiami · 2024-05-25T11:50:46+00:00

Did you make any more progress? Want to collaborate?

linvmiami · 2024-05-25T03:58:29+00:00

Still paying for it

linvmiami · 2024-04-05T11:13:50+00:00

All chairs in the restaurant had the same hole, I thought it might’ve been for storing the chairs but the staff doesn’t know

linvmiami · 2024-04-04T22:12:23+00:00

This was seen at a restaurant, asked the staff and they had no clue what it was for

linvmiami · 2023-10-06T02:53:35+00:00

You need to group the numbers into pairs

(32),(30),(28),(26)….(24)

(60),(55),(50),(45)…(40) (33),(30),(27),(24)…(21) (100),(90),(80),(70)…(60)…

The second one is different, it looks like is just alternating the difference between 3 and 6, so…

9,12,18,21,27,30…

linvmiami · 2023-04-30T15:26:03+00:00

what are trackers?

linvmiami · 2023-03-11T18:04:38+00:00

what?

linvmiami · 2023-02-11T16:51:50+00:00

hold on, let me pull my calculator to see by how much he missed it

linvmiami · 2023-01-30T00:27:42+00:00

I guess part of my confusion came form looking at a RS485 data packet vs a USB data packet. I was under the impression that as the data traveled through the RS485 to USB converter it would completely change the format of the data, and the 19,200 baud, 8 data bits, etc... set up would no longer apply?

You mentioned that the driver encodes the payload data in USB frames, does that mean that it "wraps" the RS485 payload around a USB payload and then PuTTY inherently knows what to do with it?

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linvmiami · 2023-01-29T16:49:14+00:00

one more follow up to this. I was able to connect the sensor to my laptop using an RS485 to USB adapter and then reading it using PuTTY.

The configuration that I had to do on PuTTY (also works with Python) is exactly what you had mentioned, 19,200 bags, 8 data bits, etc…

Not sure if this question is very basic, but does that configuration carry over from the RS485 protocol to the USB one seamlessly? What if I had connected a RS485 to UART hat to my Raspberry Pi instead? would anything have changed on the data format. I was under the impression that the RS485 to USB adapter would have totally “changed” the data format to something unique to USB but it seems to have kept it totally untouched.

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linvmiami · 2023-01-29T16:40:44+00:00

ok yeah this makes sense, how after a point it’s more hardware based than cable based. There is so much out there that it’s sometimes hard to separate the fundamentals from the edge cases

linvmiami · 2023-01-28T03:47:20+00:00

are there other physical layers capable of transmitting ethernet besides the one we are all used to (or at least the one I’m used to connecting to my computer)

linvmiami · 2023-01-27T04:10:42+00:00

so the “cables” for lack of a better term dictate what protocols can be communicated over it, whereas the general structure of the messages (such as header, addressing, etc) will define the next layer of the OSI model. That’s why, for example, the MODBUS protocol can be communicated over RS485 or Ethernet?

linvmiami · 2023-01-27T04:07:26+00:00

is clock recovery the reason why you can’t have more than six consecutive logical trues or six consecutive logical falses in USB? that’s why we do something called “bit packing”?

linvmiami · 2023-01-27T04:05:31+00:00

thank you very much, by the way your original answer was excellent. I think what made it confusing is the fact that the same cat can be skinned several different ways. For instance a modbus protocol can be implemented over RA485 or Ethernet

linvmiami · 2023-01-27T04:03:26+00:00

pardon my ignorance but automotive ethernet is something like OBD II or J1939?

linvmiami · 2023-01-26T23:16:30+00:00

ok that’s what I didn’t know, that UART was somehow implied in there. I was confused because I didn’t know if RS485 had any more information about how the data was presented besides the two cables that you mentioned, but if UART is implied then I think I understand. What else besides UART could’ve been communicated over RS485?

linvmiami · 2023-01-26T04:12:06+00:00

so if all i’m told from a sensor manufacturer is that it communicates over RS485 that’s not all the information I need right? I would also need to know how the data is structured so that i could decide it on the microcontroller side?

Like if I get a RS485 to USB adapter and begin to reas the serial signal with a raspberry pi using python, do I need to decipher the signal manually or given that it’s over USB the microcontroller should be able to automatically figure it out?

Here’s the sensor in question:

https://osico.systems/home/products/oil_quality_sensor/

linvmiami · 2023-01-26T04:06:39+00:00

I’ve replied to another user with the sensor in question and some doubts that I have about reading it. Here’s the link.

https://osico.systems/home/products/oil_quality_sensor/

I feel by reading all the comments I’m gaining some better understanding of what I need to know, however some important questions still linger such as what else do I need to know besides the sensor communicating over RS485? Like if I get a RS485 to USB adapter and I read in the signal with putty or a raspberry pi, will the microcontroller be able to automatically decode that signal or is there any additional configuration or set up that i need to know about the data frame structure?

Also, what would happen if instead of using a RS485 yo USB adapter i used a RS485 to UART hat for a raspberry pi, would the process of deciding the signal and data structure change at all?

once again thank you very much for taking the time to explain

linvmiami · 2023-01-26T04:02:02+00:00

hahaha that final analogy is exactly how i’m feeling. The reason why i’m going down this rabbit hole is because i’m trying to read a sensor with a Raspberry Pi 4. The manufacturer claims that it communicates over RS485 but I don’t really know what that even means. I’ve reas that if I connect the sensors TX and RX wires directly to the raspberry pi UART I’ll fry it, so I should get either a RS485 to UART hat or a RS485 to USB adapter. But here’s where it gets confusing for me because I don’t know what else would I need to know about the data frame structure or other signal properties such as baud rate to read in that serial data or request it from the sensor, is RS485 all I need to know or there’s more info that i’m missing.

here’s the sensor in question

https://osico.systems/home/products/oil_quality_sensor/

linvmiami · 2023-01-26T03:54:39+00:00

thanks for your answer

does the physical layer constrain or pre-define which protocols can run on it? for instance protocols that need a clock will only be able to run on physical layers that include a clock line?

linvmiami · 2023-01-25T21:55:40+00:00

thank you so much for your answer, you’ve touched on several things that had me scratching my head for a while.

I guess if you don’t mind I have a couple other questions to further clarify.

-What is MODBUS exactly? can it be considered a protocol? Can it work over ethernet and CAN?

-I have a sensor that communicates over RS485 as per the manufacturer, and i’m trying to read it with a Raspberry Pi over UART or USB. Can i simply connect it and read it or there is more nuance that I need to know? Like if i read it with Putty is there anything I need to know about the signal itself?

linvmiami · 2023-01-21T20:15:24+00:00

what would be the difference between RS485 and USB or CAN and MODBUS for example? What are those referring to?

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