Sharp EL-503 28 SDIP mounted upside down Chip labeled TP0327N-R MST^8022 die labeled 0320D-27 28 buttons 8-digit, 66-segment LCD -M.M.M.M.M.M.M.M Buttons Pin 17 Pin 19 Pin 20 Pin 22 Pin 24 batt + ON OFF -- -- -- Pin 5 2nd TAN COS SIN EXP Pin 6 -- / ) ( -- Pin 7 RM - 6 5 4 Pin 8 X->M X 9 8 7 Pin 9 -- = -- . 0 Pin 10 M+ + 3 2 1 0320-27 1 N/C 2 LCD common 3 LCD common 4 LCD common 5 KP row and LCD 6 KP row and LCD 7 KP row and LCD 8 KP row and LCD 9 KP row and LCD 10 KP row and LCD 11 LCD 12 LCD 13 LCD 14 batt+ and KP row 15 batt - 16 LCD 17 LCD and KP column 18 LCD 19 LCD and KP column 20 LCD and KP column 21 LCD 22 LCD and KP column 23 LCD 24 LCD and KP column 25 LCD 26 LCD 27 LCD 28 LCD 66 LCD segments S 8 7 6 5 4 3 2 1 - - - - - - - - RAD | | | | | | | | | | | | | | | | - - - - - - - - - GRAD | | | | | | | | | | | | | | | | - . - . - . _ . - . - . - . - LCD signals pin 2 pin 3 pin 4 5 D7 G7 A7 6 E6 F6 F1 7 DP6 C6 B6 8 D5 G5 A5 9 E4 F4 B1 10 DP4 C4 B4 11 D3 G3 A3 12 E2 F2 D1 13 DP2 C2 B2 16 D2 G2 A2 17 DP3 C3 B3 18 E3 F3 C1 19 D4 G4 A4 20 DP5 C5 B5 21 E5 F5 A1 22 D6 G6 A6 23 DP7 C7 B7 24 E7 F7 G1 25 DP8 C8 B8 26 D8 G8 A8 27 E8 F8 E1 28 GRAD S RAD