All of the HPR commands use the keys on the numeric keypad . This page explains the functions of each of the 17 keys. Following each key description there will be two numbers in parenthesis, separated by commas. These numbers correspond to the row and column of the key on the numeric keypad, where row 1 is the bottom and column 1 is the left hand side.
Most standard keyboards have a numeric keypad on the far right.
This keypad has five rows and four columns of keys. There are 10 numeric and 7 non-numeric keys. Zero starts reading. Enter stops reading. The History key is Num Lock.