in each of the regions and recording equipment is not interchangeable. Algorithms The actual algorithms used to encode and decode the television guide values from and to their time representations were published in 1992, but only for six-digit codes or less. Source code for seven and eight digit codes was written in C and Perl and posted anonymously in 2003. See also TrueCookPlus, a similar system for microwave oven cooking References External links VideoPlus+ & ShowView Description of the algorithm Improved software: generates and decodes VCR Plus+ codes up to 8 digits in length VideoPlus/VCR+ Codec & Trivia The Straight Dope: How do the TV program codes for VCR Plus+ work? Consumer electronics TV Guide