Creality Ender-2 Controller Board (Labeled)

This is the PCB from my Creality Ender-2 circa January 2018. It is based on the ATMega1284P with a 16MHz crystal. I have added labels for all the connectors as well as inserting better captures of the top of each of the four main ICs in the picture of the top side of the PCB. The board is 100mm long by 75mm wide. I believe that for firmware purposes this board may be equivalent to the "Melzi (Creality)" as used in the CR-10 (or at least a kissing cousin). The closest match I have found is the file "pins_MELZI_CREALITY_ENDER2.h" from TH3D Studio:

https://www.th3dstudio.com/

Points of Interest:
The only identifying label I can find is the "1748" number in the center of the board.
My 'new' spare board has the number "1804" thus there is no identifying label for this PCB.
All fans are 12 Volt DC

"FAN1" (hot end) and "FAN2" (controller fan) are always on.
Pins for connectors "LASER" and "K-FAN" are directly connected
I believe that the "K-FAN" connector can be used for addin