i meant that R1 and R2 are 8 bit ...and R1 x R2 will result in 16 bit answer...
also tell me is there any speciallize IC or Controller for Energy Meter Calculation...or if any one can help me in designing an Energy meter with help of 89c51 or 89c52 ..my idea is to use to ADC to V and I and than Multiply them and than divide the answer by 36000000 this will give u Energy of every .1 s and than add it to a counter which will count the summation of every (1/10 sec energy) can any one help me is this project ...ill be highly thankful to him.