jp2242ft Posted December 27, 2005 Report Share Posted December 27, 2005 I need to know formular if any with Grey code when using photo cell input to a weight bit. Joseph Quote Link to comment Share on other sites More sharing options...

EdwardM Posted December 27, 2005 Report Share Posted December 27, 2005 Hi Joseph"Gray codes are named after the Frank Gray who patented their use for shaft encoders in 1953" "A Gray code represents each number in the sequence of integers {0...2^N-1} as a binary string of length N in an order such that adjacent integers have Gray code representations that differ in only one bit position. Marching through the integer sequence therefore requires flipping just one bit at a time. Some call this defining property of Gray codes the "adjacency property".The above I've taken from http://cafaq.com/extra/gray.html one of the many web sites which refer to Gray codes.The most important thing about Gray codes is the fact that each angular(or linear or whatever) transition causes a change in only one bit of output. To put this in context, imagine an angle encoder system which had 10 fingers making contact with concentric copper pads and was a binary representation of angle and further that it had been calibrated in the laboratory to be perfect at 20 degrees Centigrade. So, rotating from say an angle of 15 deg (1111) to 16 deg (10000) means 5 fingers (in this example) must transition perfectly at the same time and that there must be an infinitely small gap between tracks. Imagine what happens at other temperatures? What happens when the gap in a track is not infinitely small? There are a number of angular encoding systems used in radar, not all based on Gray code - could you give some more detail?Ed Quote Link to comment Share on other sites More sharing options...

## Recommended Posts

## Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.