Screens and objects in PM Designer: buttons, switches, lamps and data entry

Three kinds of screen

Create screens with Screen > New Screen; each needs a unique number (1 to 7,999) and name (Section 3.9). The Type on the Screen Properties General page decides how it behaves (Section 3.9.1):

• Normal screen (main screen): fills the display; only one is shown at a time, and the panel remembers the last 32 so a Previous Screen button works. The start-up screen must be one of these.
• Window screen: a smaller screen that opens on top of the main screen, at the centre or at an X and Y you set, with an optional title bar and close button. Opened by a screen button, by an alarm, by a page selector, by the OPEN_WS macro, or automatically as a custom keypad. Several can be open at once, and a window with a title bar can be dragged.
• Menu screen: a window that slides in from one of six positions when its screen button is pressed, for navigation bars and side menus.

The Background page fills the screen with a colour, a pattern or a picture. The Open, Cycle and Close Macro pages attach code to the screen's lifetime, and on key-type panels the Keys page assigns the hardware keys. Screens can be exported as SNF files and imported into any project regardless of panel size, copied and pasted between applications, saved as pictures for documentation, and password-protected against editing (Sections 3.9.4 to 3.9.7).

The anatomy of an object

Place an object from the Object menu or toolbar, click on the screen, then double-click it to open its property sheet. The pages are consistent across objects (Section 4.4):

• General: the ID (BB0001 for a bit button, NE0001 for a numeric entry and so on), the shape (a graphical shape from the palette or a picture shape from the picture database, with border, pattern, foreground and background colours per state), and the operation and addresses.
• Label or Text and Picture: the inner text and picture, per state and per language, with font templates.
• Advanced: touch operation control (enabled by a bit or by the current user level), minimum hold time, operator confirmation with a timeout, a notification bit raised when the operation completes, and operation logging.
• Visibility: always invisible (but still touchable, for hidden buttons), shown or hidden by a bit, or by user level; the page also holds the exact position and size in pixels.
• External Label: a caption outside the object.
• Macro pages where the object supports On, Off or Object macros.

Objects that monitor a bit have two states; objects that monitor a word can have up to 256, decided by a state type (Section 4.4.1.1): Value uses the word's value directly, LSB uses the number of the lowest set bit (16 or 32 means none set), and Custom maps chosen values to states. Addresses are typed directly, built with the Address Input Keypad, or picked from the tag list (Sections 4.4.3.2 and 4.4.3.3).

Buttons and switches (Chapter 5)

Lamps and message displays (Chapter 6)

A bit lamp shows one of two appearances from a bit, a word's bit or a double-word's bit. A multi-state lamp shows up to 256 appearances from a word by Value, LSB or Custom state type, each state with its own text, picture and colours. A message display shows one of up to 256 predefined messages from a word, or, with the "value as string number" state type, any of up to 20,000 strings from a text table, which turns a PLC status code straight into readable text; a marquee option scrolls a long message. The difference from a lamp is that a message display is text-first and can draw from the text database, while lamps are shape-first.

Entering and displaying data (Chapter 7)

A numeric entry writes a number to a variable through the built-in keypad (decimal, hexadecimal or octal, with a calculator), and a numeric display only shows one. Both take a Data Type (8-, 16- and 32-bit integers, BCD, float), a Display Type (decimal, hex, octal, binary, exponential, IP address) and digit counts. The Advanced page holds the three options that make them useful in practice:

• Scaling: either gain and offset (displayed = raw x gain + offset, and the inverse on entry) or a data min/max mapped to a display min/max. Gain and offset are floats with about 6 significant digits.
• Range check on entries: a value outside the minimum and maximum is refused and the keypad shows the allowed range; with scaling, the output value is what is checked.
• Range display: colour the value differently below a low limit or above a high limit, with fixed or variable limits.

An advanced numeric display adds an arithmetic expression or a macro to compute the displayed value and to convert an entered value, up to 10 colour ranges, a keypad timeout, notification and operator confirmation. Character entries and displays handle ASCII, Western European, Cyrillic and simplified Chinese strings (Unicode on the Windows runtime), with a Pinyin keypad for Chinese. Time, date and day-of-week displays show the panel clock in a choice of formats and need no address at all.

Drawing, pictures and animation

The Draw menu provides dots, lines, polylines, rectangles, circles, ellipses, arcs, pies, polygons, text, pictures, scales and tables (Section 4.1). Shapes can change colour from a control bit, so a static line becomes a pipe that lights when flow is on. Pictures come from the project's Picture Database (BMP, JPG, GIF, WMF, SVG, PNG) and picture groups give an object one picture per state. Chapter 9 of the manual covers the animated objects: pipelines with flowing segments, dynamic lines, rectangles and circles whose position, size and colour come from PLC words, GIF and picture displays, animated graphics that move along a path, and path displays. Use them sparingly on the smaller ARM panels; every animated object is redrawn continuously.

Editing screens quickly

• Shift-click to add to a selection, Ctrl-click to choose the reference object, then Edit > Align and Make Same Size (Section 4.2.4).
• Edit > Duplicate lays out a grid of copies with an address increment, so eight pump buttons on consecutive coils take ten seconds (Section 4.2.3).
• Group objects to move them as one, and save a group to the object library for reuse in other projects.
• The Off and On toolbar buttons preview every object in state 0 or 1; the State box previews higher states.
• The Text Database (Project menu) edits every string of every language in one grid and imports and exports CSV, which is how translations are done (Section 2.2.5).
• Keep one font template per text size and use it everywhere; changing the template changes the whole project (Section 2.2.2).

User levels and passwords

Panel > Passwords (Section 3.8) defines up to 8 user level passwords (positive integers up to 8 digits) plus the developer password as level 9, or up to 32 named users at runtime. Any touchable object can require a minimum user level on its Advanced page and the panel pops up the password keypad automatically when a lower-level operator touches it; the Visibility page can hide objects below a level altogether. A login trigger bit, a logout trigger bit and a login timeout complete the scheme, and $S219 exposes the current level to macros.