Math Star 40 SDIP Chip labeled CD4616N2L M B 8817 5931 PHILIPPINES die labeled 0456B CD4616 24 buttons 7-digit LCD with symbols, 74 segments 1 N/C 2 N/C 3 KP column 6 4 KP column 5 and LCD segs 5 KP row 4 (top) 6 KP column 3 and LCD segs 7 KP column 4 and LCD segs 8 KP row 3 9 LCD segs 10 LCD segs 11 N/C 12 N/C 13 KP row 2 14 KP column 1 (right) and LCD segs 15 KP column 2 and LCD segs 16 KP column 5 17 battery - 18 battery + and KP column 7 (left) 19 LCD common 1 20 LCD common 2 21 LCD segs 22 LCD segs 23 N/C 24 N/C 25 N/C 26 N/C 27 LCD segs 28 LCD segs 29 LCD segs 30 LCD segs 31 LCD segs 32 LCD segs 33 LCD segs 34 LCD segs 35 LCD segs 36 LCD segs 37 N/C 38 N/C 39 LCD common 3 40 LCD common 4 Buttons Pin 18 Pin 3 Pin 4 Pin 7 Pin 6 Pin 15 Pin 14 Pin 5 n/c n/c n/c 7 8 9 / Pin 8 Memory Bank Electro Flash Time's Up 4 5 6 x Pin 13 OFF Secret Number Force Out 1 2 3 - Pin 16 ON Missing Number GO 0 n/c = + 74 LCD segments * * * * * * * * * - - o - - - - - 1 | | | | \|/ | | | | - | | | | | | 7 2 - - - - - - - - 6 0 3 | | | | /|\ | | | | - | | | | | | 5 4 - - o - _ - - - 10 9 8 7 6 5 4 3 2 1 LCD signals pin 19 pin 20 pin 39 pin 40 4 n/c star 4 equals n/c 6 4F 4A 4E 4D 7 4B star 3 4G 4C 9 2F 2A 2E 2D 10 2B star 1 2G 2C 14 circle circle circle circle center arc 1 arc 7 arc 6 15 circle circle circle circle arc 3 arc 2 arc 4 arc 5 21 3B star 2 3G 3C 22 3F 3A 3E 3D 27 6B star 5 6G 6C 28 6F 6A 6E 6D 29 7B star 6 7G 7C 30 7F 7A 7E 7D 31 upper star 7 8G lower left \ left / 32 right / upper plus sign lower \ dot verticals dot 33 9B star 8 9G 8C 34 9F 9A 9E 9D 35 10B star 9 10G 10C 36 10F 10A 10E 10D