Selector
Registered options over one point, as keys or a list, showing which one the plant is actually in.
Selector offers the operator a closed set of registered choices (an operating mode, a recipe, a speed step) over one writable point. Picking one writes that option's value; the same point read back is what lights the active option. That read-back is the whole reason the kind exists: a row of Buttons each writing a fixed value writes just as well and shows nothing. It is a Control component; a new one occupies 5 × 1 cells.
Data
| Field | What it does | Values | Default |
|---|---|---|---|
| Address | The rooted Logic address the choice is written to and read back from: a memory variable or a writable tag. The list is narrowed to points that can actually be written. | Free text; writable-point suggestions | empty |
Options
| Field | What it does | Values | Default |
|---|---|---|---|
| Shows | How the options are offered: one key per option, side by side, every choice readable at once, or a list that opens on demand, for a cell with no room for a row of keys. | A key per option · A list that opens |
A key per option |
Each option is one card holding the two things an option is:
| Field | What it does | Values | Default |
|---|---|---|---|
| text | The word the operator reads on the key or in the list. Blank falls back to the value itself, because a key with nothing on it says nothing. | Free text | empty |
| value | The value written when this option is picked, and the reading that shows it active. It is a code, matched exactly: what lies between two codes is not a choice. | Any number | empty (declares nothing until typed) |
The order of the cards is the order of the keys under the operator's hand: the move up / move down arrows reorder; nothing here sorts itself. Two options naming the same value cannot both draw a key (the point could report only one of them, and the control could not say which); the panel says so and the duplicate draws nothing.
All keys share one type size, reserved from the widest registered word, so the row reads as one control rather than a row of unrelated keys. A Selector with no options says "No options registered." instead of drawing an empty row that looks like a screen still loading.
What lights, and when
The lit key (or the list's selection) is the point's own reading, never the click:
| Situation | The control shows |
|---|---|
| The point reports a registered value | That option lit, or selected in the list |
| The point reports a value no option registers | Nothing lit: the nearest key lighting up would be the screen inventing the plant's mode |
| The point is not reading | Nothing lit, and the component wears the shared bad-reading mark |
A pick asks for no reading first (the option carries an absolute value), so bad quality leaves the control usable while taking the indication away.
Write semantics
Picking an option writes its value through the station's single logic funnel, under the same authorization every command passes. A point that cannot hold a number refuses the write with the reason on the control's answer line ("This point holds date and time, so 2 is not a value it takes."); a successful pick answers with the option's word ("Auto written"). The answer line expires after a few seconds, and authorization is re-checked at every pick. Where the options are shown as keys, in a cell with no room for that line and no corner title standing over the row, the answer takes the word of the key that was pressed while it shows, a refusal in the error ink. The key keeps its width, so what it cannot hold ends in an ellipsis with the whole answer in the tooltip; no key moves, and the word comes back when the answer expires. Where the options are shown as a list, the answer takes the place of what the closed list shows in the same way: the list keeps its width and its arrow, and what it showed comes back when the answer expires.
Over a tag whose Limits stage is on, an option whose value lies outside those limits is refused the same way, with a reason that names those limits, and nothing is written: taken at the edge, it would put the plant in another option than the one picked, and the line would confirm the one picked.
Over a point that holds integers (a tag of an integer type whose Scale and Calibration leave the value unchanged, or a memory variable holding integers), an option whose value has a fraction is refused the same way rather than rounded ("This point takes an integer, so 2.5 is not written to it."), and nothing is written.
Permissions and the lock
Operating the Selector needs the role permission to operate dashboards. A blocked press disables the keys and draws the shared lock mark with the reason in the component's tooltip (see the dashboards page).
The shared Appearance, Identification, Position and layer and Actions sections are described on the components page.