RS-485 Polarity: Difference between revisions

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(Created page with "RS-485 comprises two signals, one that 'tracks' the logic levels (high voltage == 1, low voltage == 0). The other signal does the opposite. The labeling of these two signals has been polluted by chip and box vendors, which leads to a lot of confusion. This article attempts to resolve the status without adding to the confusion Our terminology: {| class="wikitable" |+ Caption text |- ! Our Terminology !! Description !! Logic levels !! Data Representation |- | T+ || Track...")
 
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| Our terminology || T+ || T- || Nominal || BITS
| Our terminology || T+ || T- || Nominal || BITS
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| Example || Example || Example || Example
| || + || - || Symbol || FT-Click, BASRouterLX
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| Example || Example || Example || Example
| || B+ || A- || || MBS UBR-01 MkII
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| Example || Example || Example || Example
| || U+ || U- || || [https://en.wikipedia.org/wiki/RS-485 Wikipedia]
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| Example || Example || Example || Example
| Example || Example || Example || Example

Revision as of 05:28, 17 September 2023

RS-485 comprises two signals, one that 'tracks' the logic levels (high voltage == 1, low voltage == 0). The other signal does the opposite. The labeling of these two signals has been polluted by chip and box vendors, which leads to a lot of confusion. This article attempts to resolve the status without adding to the confusion

Our terminology:

Caption text
Our Terminology Description Logic levels Data Representation
T+ Tracking High voltage (typically +5 or +3.3) 1
T- Non-tracking Low voltage (close to 0v) 0


Labeling found in the field

Caption text
Comment Tracking Non-tracking Class Manufacturer examples
Our terminology T+ T- Nominal BITS
+ - Symbol FT-Click, BASRouterLX
B+ A- MBS UBR-01 MkII
U+ U- Wikipedia
Example Example Example Example
Example Example Example Example
Example Example Example Example
Example Example Example Example
Example Example Example Example
Example Example Example Example