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METP0000

LCD Description

ModelMETP0000
ManufacturerMettler Toledo
Recovered fromMettler Toledo Model 8217 scale
Board IDsOPCVO, METP0000 REV B
LCD type
Polarizer typereflective
Columns6
Rows1
Char matrix7 segment with underscore, decimal point and comma
Driver ICNEC μPD7225 1) 2)
Backlight-
Arduino driver
ConnectorRJ45
Num Pins8
Pin spacing“
Arduino test rig 3)
Pin#LabelIC pinLabelPincolour
1Busy ~Busy-white/orange
2Reset ~ResetD7orange
3Si SiD5white/green
4SClk ~SCKD4blue
5CS ~CSD8white/blue
6~C/D C/~DD6green
7GND20VssGNDwhite/brown
8+5V21Vdd+5Vbrown



Appears to be wired for 1/3 bias, divide by 3 or 4 time division. Comma and underscore may be implemented as segments of extra characters (ie 7th and 8th digits??). 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. Mode byte appears to be 0x48. 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.


Examples :

METP0000

METP0000

METP0000

METP0000

METP0000

METP0000

3)
reminder for my personal testing, not useful for anyone else!