Napier's Chessboard Calculator - Addition

The addition version of Napier's Chessboard Calculator identifies each column on the board by the binary positional value of the numbers to be represented in each row. Thus the starting stage is to enter the numbers to be added together in the rows of the board, either by clicking on the board cells or by entering the desired value in the textbox alongside each row. [NOTE: when the text box is used as the data entry method, click on the ENTER button before proceeding.] After data entry, row values may be changed either by adding or deleting chips or by re-entering the text box value. Any row (except the bottom row that is reserved for the final result) can be used to enter data items.

Once the data has been entered, all the chips need to be slid down to the bottom row by clicking on the SUM COLUMNS button. In this mode where there are more than one chip in a cell, the chip color will change from red to purple. The decimal value of the sum will be shown in the text box to the right of the bottom row. Obviously since the calculator uses the binary notation for the representation of numbers, it is not appropriate to have more than one chip in any cell. However, two chips in a single cell is equivalent to one chip in the cell to the left. Thus by clicking on a purple cell the manual operation of picking up two chips from a cell and placing one chip in the cell to the left is emulated. You should click on purple chip sets until each cell contains at most one red chip. At the point the proper binary representation will be in the bottom row.


Last updated 2001/08/09 
© J..A.N. Lee, 2001.