CASIO fx-3600P scientific calculator

Made after 1985, according to the Hitachi HD43147 SoC processor.

Calculator forensics: arcsin(arccos(arctan(tan(cos(sin(9)))))) = 9.0000157179

Tested in DEG mode.
Typed: 9 sin cos tan INV tan INV cos INV sin
Result1: 9.000015718
Typed: - 9 =
Result2:  1.57179 -05
Typed: x 1000000 =
Result3: 15.7179

Front panel was lose due to film dry glue.

Single 3Volt CR2025 Lithium battery cell.

Two classic axial pass through mount 1/8 Watt, 5% resistors on the PCB back side.
Top = 390 Ohm, Bottom = 220KOhm

PCB front side.
Keyboard keys assembly (foil membrane attached to the PCB).

One unmarked SMD ceramic capacitor.
And the Hitachi HD43147  SoC processor, made in 1985 week 43 (5J 43).

Keyboard rubber membrane.

Real quality plastic keys, where the bottom half sports injection moding manufacturing.

 
Partial exploded view.