Datamax ST-3210 Operator's Manual page 19

"Standard Media Sensor" using Fan-Fold Stock –
With the ticket TOF Marks facing 'down' (away from you),
place the ticket stock in the bottom of the printer. (If using an
external supply, route the ticket stock into the printer through the
Rear or Bottom Slots.)
Ensure that the Printhead Latch is in the 'Locked' position.
Rear Slot
Bottom Slot
Thumbscrew
Printhead Latch
S-Class
Media
Guides
Ticket Stock
Unlocked
Locked
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