Talk:Wired logic connection

What function represents wired logic - AND or OR?

What is wired-OR logic? How do we realise this logic? Does the active level of the connected signals make the difference?

They are both wired logic depending on how the diodes are wired and where a resistor, if any, is placed. With a wired-AND, the levels would matter. A wired-OR is when you put 2 cathodes of diodes together. If a signal goes through either line, you get a high signal on the output. The diodes isolate the signals from 2 or more lines so it can't pass to the other line and go up the bus. This is often used for other uses such as voltage isolation such as in a USB device that is externally powered. Thus the USB cannot send voltage to the batteries or external adaptor and the external source cannot feed the USB port or compete with it. A resistor often isn't required.68.67.254.133 (talk) 03:41, 11 December 2019 (UTC)

Wired OR not described correctly

No diodes are needed in wired or using tristate logic. See http://www.ni.com/product-documentation/3544/en/ --agr (talk) 00:00, 25 April 2019 (UTC)

However, if you use an IC, that is not a "wired-OR," since that is not a "passive component."68.67.254.133 (talk) 03:45, 11 December 2019 (UTC)

No diodes are needed. Though specifically not tri-state but rather open collector (and its variants open drain, open emitter, open source). I'm going to rewrite these examples using open-collector outputs only, and will simply point to the diode logic page to show how to do it using diodes. Em3rgent0rdr (talk) 19:21, 18 January 2023 (UTC)

(edit) I'm considering using the symbol for open-collector buffer: https://www.ti.com/lit/ds/symlink/sn7407.pdf Em3rgent0rdr (talk) 19:41, 18 January 2023 (UTC)

I made an svg version of the official symbol for open collector or open drain output. I'm going to use that for the circuits.

Open-collector or open-drain buffer

Em3rgent0rdr (talk) 22:51, 18 January 2023 (UTC)