The ROMs or PROMs must have the correct code for converting the data from the NE5037-used as address for the ROMs or PROMs-to the appropriate segment driver codes. The displayed amount could easily be converted to degrees Fahrenheit, °F, by the controller of (0 - 63 °temperature sensor) or through the (P) ROMs. When doing this, a third (hundreds
) digit (P)ROM and display will be needed for displaying temperatures above 99 °F. An expensive clock can be made from NAND gates or inverters as shown.