Kroy 360


This keyboard module was OEMed for Kroy.

This keyboard module is special to this lettering system. Lettering systems were the label makers of the day and included a separate printer. These systems have a motherboard and another board for the keyboard module. The Motherboard allows the lettering system to accept other fonts through the expansion slot. These font cards could be purchased separately. The keyboard module seems to be the only part of the letting system that was produced by NMB. 

The lettering that is going to be printed on the label is displayed on the LCD.



The keycaps are made out of PBT with dye-sublimated legends. These keycaps are unique to this keyboard as they use a different font and unique colorway. 

The keyboard with special letting legends also has front-facing legends as well that describe other operations that can be performed with the keys.

Something special with these caps is the use of a 9u spacebar.

Upper Case

The upper case is made out of a single piece of beige ABS plastic. The plastic is textured and painted.

Lower Case 

The cases is made out of a single piece of beige ABS plastic. The plastic is textured due to the molding process that is used to create the lower case. 

Switch Plate

The switch plate is made out of stamped steel. The plate is bent on either so that it can be mounted to the upper case. The plate is painted with a thin layer of black paint. The paint is then protected by a thin layer of oil to prevent rust.



Front Printing


Spacebar Switch

PCB Markings



Main Switches

Plate Model Sticker

Replacement Motherboard

Model Label

PCB/Keyboard Interface

The Kroy 360 keyboard unit is connected to the printer unit via flat coiled cable with 8P8C module jacks. This connection is used to provide power from the printer to the keyboard and transfer label print information from the keyboard to the printer. This connection can not be used to determine what keys have been pressed. In order to interface the keyboard on a per key basis, the internal header on the keyboard pcb must be used.

The keyboard unit can be used in a standalone configuration by supplying 5V via the DC barrel jack on the rear panel. The size of the barrel is 6.3 mm OD x 2.5 mm ID but the more standard 5.5 mm OD x 2.5 mm ID size will work. Note: The polarity of the power jack is center negative while most commonly available wall-wart style power supplies are center positive.

The keyboard unit contains a keyboard assembly and a mainboard. The two are connected with a 20 pin ribbon cable using female 2x10 connectors with 2.54mm pitch. The pinout of this connection is the same on both the mainboard and keyboard.


Timing Diagram

Key scan codes are sent as a 7 bit, parallel value on data lines D0 through D6.

When a key is pressed, Key State(KS) will transition from low to high and Data Ready(DR) will pulse low. The host issues a Continue(CT) with a low pulse to acknowledges data reception. Note: if the Continue pulse is sent too soon after the Data Ready pulse is received or the pulse is too short, the keyboard may miss it. A delay of 100us and a pulse width of 20us has been used succesfully.

When a key is released, Key State will transition from high to low and DR/CT handshake will repeat. Data Ready can be used to latch/read data from data lines D0 through D6.

Note: Key State (Pin 3) tracks the last key event and is common to all keys.

Scan codes

The scan codes generated by the keyboard via the 20 pin header are shown in the diagram below:

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