CS61C L13 I/O © UC Regents 17 % Processor time to poll mouse, floppy °Mouse Polling Clocks/sec = 30 * 400 = 12000 clocks/sec % Processor for polling = 12*10 3 /500*10 6 = 0.002%  Polling mouse little impact on processor °Times Polling Floppy/sec = 50 KB/s /2B = 25K polls/sec Floppy Polling Clocks/sec = 25K * 400 = 10,000,000 clocks/sec % Processor for polling = 10*10 6 /500*10 6 = 2%  OK if not too many I/O devices
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