[Sir_Cmpwn]

"Asserted" is a past-tense verb, which implies a process of checking that it's valid at a certain moment in time, before proceeding some some work that requires it to be so. If I understand correctly (and I may not), the case is rather that the bits are always set, in which case I might call them "pinned" to 1 or "fixed" to 1 - meaning they cannot change, rather than should not change. It might also be that they are set to these values automatically during boot, but can be changed by the firmware - in which case "initialized" could be better.

Or at least that's the source of confusion for me, maybe the terminology is different at this level.

[Filligree]

> Or at least that's the source of confusion for me, maybe the terminology is different at this level.

Others have mentioned it is.

The reason why 'asserted' is used is that signals at this level are basically analog. The circuit that asserts a signal is, fairly literally, being assertive, and there are all sorts of commonly used options: Pull-ups and pull-downs, either one in either weak or strong (assertive) form.

Connecting a strong pull-down to a strong pull-up represents a short circuit, but having one circuit assert a logical 1 while the other circuit on the same pin holds a weak pull-down (presumably, in this case, 0), is a pretty common configuration.

The most important thing to keep in mind, working with electronics, is that all pins must be connected to at least a weak pull-up/down, which can be as simple as an MOhm-class resistor connected to ground.

If they aren't, then the gate is floating -- and a floating CMOS gate can easily reach states where the gate itself is short-circuiting, since they're made from a transistor pair connected to both ground and power. (As is necessary to support both pull-up and pull-down.) If that doesn't destroy the gate -- check your datasheet -- then, at a minimum, it'll still waste power.

The majority of common microcontrollers (e.g. Arduinos) will allow you to configure the gate with a internal weak pull-up/down, to let you avoid connecting every single pin, but you shouldn't assume that it's configured that way out of the reset vector. Nor that such an internal pull-up even exists.

[dfox]

Asserted is standard term used in electronics for "having the logically active state" used when whether that means one or zero on the physical wire is irrelevant. In particular Intel's documentation uses "asserted" in this sense.

[bytefire]

ah i see your point. here asserted defines a state and not a way of ensuring a certain condition is met (as in higher level languages). yes "initialised to 1" would also convey same meaning. i hope it's clearer now. the term asserted is often used in electronics and i can see how it can be misleading.

[Sir_Cmpwn]

Thanks for clarifying!

[danaliv]

The terminology is different at this level. Asserted means the lines are set to whichever voltage is logically 1.

[0xcde4c3db]

To me, "asserted" implies a control signal whose semantics aren't numeric. That is, it's describing a true/false or on/off state ("is this condition present?") rather than a binary digit. For an address or data bus I think it's fine to just use "1".