Customer displays at the POS: setup, common faults, and what shoppers should see

Store operations · 7 min read

Checkout counter with a POS terminal, a large blank customer-facing screen and a basket of groceries — Two screens, two audiences: the cashier terminal and the customer-facing display.

"The customer display isn't working" is three different problems wearing one coat. In LS Central it can mean the second screen that shows the running sale, a small two-line pole display that shows item and total, or — in other POS products entirely — a spare tablet paired over the network. The setup, the faults, and the fixes are different for each. This guide separates the two LS Central routes, walks through the Dual Display setup fields, sets out what a shopper should actually see at each stage of a sale, and finishes with faults in the order worth checking them.

Two different things are called a customer display

	Dual Display	Line display
What it is	A customer-facing program on a second screen, showing the transaction or selected store offers	A small hardware display device, handled as an OPOS device
Where it is configured	In the LS Central BackOffice — enabled on the POS Terminal Card, with its own panels from the POS Profiles	Through the LS Hardware Station, after its driver is installed and tested on that machine
How it starts	By default on the secondary screen when the POS runs; in full-screen mode when the POS runs inside the LS Central app (Windows AppShell)	Loaded as a device in the Hardware Station Management Portal, like the printer or scanner
What it can show	Full panels — sales lines, offers, media — limited to display-only controls: Data Grid, Button Pad, Media, and Browser	Short device messages; the Management Portal itself can send it a test message

Everything below about states, panels, and slideshows is Dual Display. The line display gets its own short fault section at the end, because mixing the two is how a configuration check turns into an unnecessary hardware order. One version note, verified against LS Retail's own release overview: LS Central 24.0 (released April 9, 2024) added an option for an interactive panel on the dual display in the restaurants and forecourt context, with configuration for what the screen and its buttons show. On the standard setup described here, treat the display as display-only unless that option has deliberately been enabled for your terminals.

Setting up the LS Central Dual Display

The configuration lives in one place: the Dual Display FastTab on the POS Terminal Card for the terminal in question. The Dual Display is configured in the BackOffice and must be enabled there to run — a second monitor plugged in and working in Windows is not, by itself, a configured customer display.

Connect the second screen and confirm Windows sees it. The Dual Display starts by default on the secondary screen when the POS is run, so the screen has to exist as a secondary screen before the POS starts.
Open the POS Terminal Card and select Dual Disp. Enabled. Without this field set for that terminal, nothing else on the FastTab matters.
Assign the three Dual Display profiles. The FastTab carries a Dual Disp. Interface Profile, a Dual Disp. Menu Profile, and a Dual Disp. Style Profile — the primary profiles the Dual Display program runs with. The display has its own panels and uses controls and menus from the POS Profiles, so an empty or wrong profile shows up as a blank or wrong-looking display, not as an error.
Set the slideshow, if you want the idle screen to earn its keep. The Dual Disp. Slideshow field takes a Media Playlist Number. That playlist is what the display runs after it has connected to the POS client and nobody is logged into the POS. Leave it empty and the logged-out state has nothing to show.
Check the screen number only if you have more than two screens. Dual Disp. Screen is 0 by default and does not need changing in a normal two-screen setup. With extra screens, set it to the screen the display should run on — 3, for example, for the third screen. One hard rule from the LS documentation: the Dual Display cannot run alongside the POS on screen one.
Start the POS and walk around to the customer side. Confirm the display starts on the customer screen — full-screen if the POS runs in the Windows AppShell — then check each state in the next section.

What success looks like: logged out, the customer screen shows the offline panel or your slideshow; during a sale, scanned lines appear on the customer screen as they are added; at payment, the display switches to its payment panel. If any state shows the wrong screen, a Windows desktop, or yesterday's panel, the fault is in the FastTab fields or the profiles — not in the monitor.

One refinement worth knowing: the sales lines on the Dual Display can be updated separately from the POS's own sales lines. That takes a dedicated Interface Profile for the Dual Display with its own Journal Data Table assigned, which is then set in the Dual Disp. Interface Profile field on the terminal card. It is how a store shows a trimmed customer view — fewer columns than the cashier's journal — without touching the POS layout itself.

What shoppers should see, state by state

The Dual Display runs three states, and each state has its own panel. Most "the display is showing the wrong thing" reports are really "the display is in a different state than the cashier thinks it is":

State	When it runs	Panel	What the shopper should see
Offline	No employee is logged into the POS	#DD-OFFLINE	The offline panel, or the slideshow playlist if one is assigned — offers and store content, not a sale
Sales	The POS is in Sales Mode	#DD-SALES	The items being sold in the current transaction, as they are scanned
Payment	The POS is in Payment Mode, after Total has been pressed	#DD-PAYMENT	The payment-stage view. It can differ from the sales panel, or be a copy of it — both are valid setups

Use the table as the acceptance test after any setup change: log out and look, log in and scan one item and look, press Total and look. Three glances from the customer side catch profile and panel mistakes that an hour of BackOffice staring will not, because the panels are display-only by design — a panel built with the wrong control types simply has nothing valid to show.

Common faults, in the order to check them

Symptom	Check first	Why
Customer screen completely dark	Power and the video cable at both ends; then whether Windows still sees a second screen	A display the operating system cannot see is a screen or cable problem; LS Central settings come after that
Display shows the Windows desktop or the POS itself	Dual Disp. Screen on the POS Terminal Card, and that Dual Disp. Enabled is set for this terminal	The display starts on the secondary screen by default and cannot run on screen one; a wrong screen number or a disabled terminal puts content in the wrong place
Display stuck on the idle screen during a sale	Which state the POS is in: the offline panel runs while nobody is logged in, and the slideshow runs after connection while the POS is logged out	What looks frozen is often the correct offline panel — the sale state never started because the login state never changed
Display shows a sale, but the wrong layout or missing lines	The Dual Disp. Interface, Menu, and Style profiles, and the Journal Data Table assigned to the Dual Display's Interface Profile	The display runs its own panels and can use a separate journal data table from the POS, so its view can legitimately differ — or be misassigned
Display stuck on an update or splash screen for hours	Power the register down, physically reconnect the display, and restart — the sequence that resolved a widely reported case of a customer display sitting on an update screen all morning	Displays that mirror a register can wait on the register; a clean reconnect and restart is the field fix before anyone escalates

The order matters: physical connection, then terminal-card fields, then profiles. Working it backwards — rebuilding profiles for a display whose cable is half out — is the most common way this fault eats an afternoon.

Line display faults

A pole or line display takes the other route. Line Display is one of the devices the LS Hardware Station supports — most standard devices there are OPOS devices — and in the Web POS the supported set via Hardware Station is the cash drawer, scanner, line display, printer, and EFT. So a dead line display is troubleshot like any other Hardware Station device, in this order:

Driver first. The line display's driver must be installed and tested on the machine running the Hardware Station service before the device is added — the same prerequisite LS Retail sets for OPOS printers and drawers.
Loaded in the portal? Open the Hardware Station Management Portal (http://localhost:8088 by default; the service itself defaults to port 8082) and confirm the line display is loaded. After a service restart, refresh the portal page to reconnect.
Send the portal's test message. The Management Portal can perform basic operations such as displaying a message on a line display. If the test message appears, the device, driver, and service are healthy, and the fault sits in the POS configuration above them. If it does not, work downwards: cable, port, driver.
Then the Hardware Profile. Confirm the profile synced with the Hardware Station and that Detect Hardware brought the line display into the terminal's profile — a device added to a profile by hand is not guaranteed to be loaded in the Hardware Station.

FAQ

Is a line display the same thing as the Dual Display?
No. The Dual Display is a BackOffice-configured program on a second screen with its own panels and profiles. A line display is a hardware device handled through the Hardware Station as an OPOS device. They are set up, tested, and fixed in different places.

Can shoppers interact with the Dual Display?
On the standard setup, no — its panels are display-only and can contain only Data Grid, Button Pad, Media, and Browser controls. LS Central 24.0 added an optional interactive dual-display panel in the restaurants and forecourt context; unless that option was enabled for your terminals, expect display-only.

The display shows fewer columns than the cashier's screen. Is that a fault?
Not necessarily. The Dual Display can be assigned its own Journal Data Table through a dedicated Interface Profile, so its sales lines update separately from the POS lines by design. Check the assigned data table before treating it as a bug.

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