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LCD Description
Model	METP0000
Manufacturer	Mettler Toledo
Recovered from	Mettler Toledo Model 8217 scale
Board IDs	OPCVO, METP0000 REV B
LCD type	positive
Polarizer type	reflective
Columns	6
Rows	1
Char matrix	7 segment with underscore, decimal point and comma
Driver IC	NEC μPD7225 ¹⁾ ²⁾
Backlight	-
Arduino driver
Connector	RJ45
Num Pins	8
Pin spacing	“

				Arduino test rig ³⁾
Pin#	Label	IC pin	Label	Pin	colour
1	Busy		~Busy	-	white/orange
2	Reset		~Reset	D7	orange
3	Si		Si	D5	white/green
4	SClk		~SCK	D4	blue
5	CS		~CS	D8	white/blue
6	~C/D		C/~D	D6	green
7	GND	20	Vss	GND	white/brown
8	+5V	21	Vdd	+5V	brown

Appears to be wired for 1/3 bias and divide by 3 or 4 time division.
Some testing was done with mode byte set to 0x48 = 1/3 bias method, divide-by-3 time division drive , frequency division ratio 1/2^7 (frame frequency=fCL /(2^7 × 3)). Digits are 7 segment plus decimal point and comma on the 2nd through 6th character (from left to right), plus 5 “underscore” characters evenly spaced below the line of digits. The decimal point to the right, and the comma to the left of each digit appear to be one unit, except for the first and last digits. For the first digit the underscore replaces the decimal point. And for the last, the underscore replaces the comma. But all segments couldn't be addressed, 3 of the underscores may be implemented as segments of extra characters (ie 7th and 8th digits??), and segment “f” and “c” weren't conrolled by 8 bit words. There are 10 individual elements to each character - 7 segment digits plus decimal point, comma and underscore, maybe this board is setup as a 14 segment display.

Data and control lines are buffered by inverting schmitt triggers (74hc14), so the driver software needs to invert all those signals.

The front keypad switches appear to be encoded by a 74HC165 shift register and wire-ORed to the pin 1 output line.