Although accurate digital thermometers

are now available at low cost, it remains

exciting and instructive to build one your-

self. The present circuit is particularly

intended to help the reader in the use of

a PIC processor Type PIC16F84 (see

www.microchip.com), a temperature sen-

sor with 1-Wire protocol Type DS1820

(see www.maxim-ic.com), an LCD screen

with 2x16characters (HD44780 com-

patible) and a light sensor with an LDR

that determines whether the background

lighting of the LCD should be on