The gate screen

The screen pupils scan their cards on as they come in, on the registered tablet.

What it is for

It records a pupil's arrival when their card is scanned or their code typed, and says at once who they are, in which class, and whether they came on time or late.

Step by step

Keep the screen open on the tablet: the field at the top is ready to scan, so scan the card with the scanner, or type the pupil's code and press “Check in”, or press “Camera” for the tablet to read the card with its camera.
The answer shows in the big frame: the name, class, code and the time of the scan. Green “Checked in” is a pupil on time, amber with “Late by … minutes” a late one, red “Absent (arrived late)” a pupil who arrived after their shift's “Absent after” and was recorded absent, the group's colour “Already in” one already recorded present, late or excused, red “Absent” one already recorded absent (on the register, at the close or by an earlier scan), and red too what was not recorded: an unknown code, a pupil of another school, an inactive pupil or one in no class, or no shift today, or “Old card: print it again” for a card printed before the private code.
If the network drops, keep scanning: scans are kept on the tablet and sent when it is back, with “Waiting to send” and their count. What the server refused shows at the foot with “Try again” and “Discard them”; discarding asks you to confirm because it drops those scans, so record those pupils by their code on the gate page.
“Full screen” widens the screen, and “Install the app” puts it on the tablet as an app.
There is no menu on this screen and no button to leave it: it is the tablet's only page and stays open with its registration until the school revokes the tablet under “Gate tablets”, and then the screen says so. Full screen ends the way the device ends any full-screen page.

How it works

The screen answers from the list of the tablet's school's pupils that it loaded, then the server confirms each scan and its answer replaces the first; the tablet holds only the pupil's name, code, the private code of their card and class, no identity number or mobile. A card is matched by its private code alone, so a pupil's number by itself is “Old card: print it again” and records no arrival. A card that carries the identity number is asked of the server first, and its number is kept on the tablet only sealed with the server's key when the connection is down, so only the server can read it. The screen judges by the same shift minutes as the server (late and absent, with the grace minutes), so a pupil who arrives after “Absent after” is recorded absent and the screen says “Absent (arrived late)”; a scan past “Absent after” never changes a mark the teacher set on the register. The tablet has an account of its own at one school and opens nothing but this screen.

On the page

Scan the card or type the pupil's code and press “Check in”, or start the camera.
The last scan's answer: green for on time, amber for late, red for a pupil recorded absent for arriving late or for what was not recorded.

Questions

Red with “No shift today”?: The pupil has no shift at the school on this day, so their arrival was not recorded.
Red with “Old card: print it again”?: The card was printed before cards carried a private code and carries the pupil's number, so the arrival was not recorded. Ask the office to print it again from “Pupil cards”.
The screen says the tablet was revoked?: Ask whoever manages the tablets to register it again under “Gate tablets”; registered again as the same tablet, its kept scans are sent.