The influence of the instruction codes on radiated near-magnetic-fields $a case study on A5000

It has been said that the radiated electromagnetic emission (EMI) spectra from the computer change with the kind of the program executed on the computer. In this study, as a first step to investigate the influence of program on EM, the influence of instruction codes executed on a CPU on radiated near-magnetic-field is clarified by experiments and investigation on the timing chart of a CPU. It is concluded that the frequencies having peaks of near-magnetic-field spectra are observed on every frequency obtained by dividing the clock frequency by the number of clocks required for one instruction execution.