cs581 G. W. Cox -- Fall 2004 The University Of Alabama in Huntsville Computer Science Example SW/HW Model: System Sensor Processing SW/HW Sensor input Calibration Flag System description: Waits for input from sensor (sensor inputs provided each 2ms). When input is available, processes it (see SW description). Following processing, checks state of Calibration Flag; If flag is set, conducts calibration processing. (Calibration flag set each “c” ms where c is distributed as N(50,100), c>=20). After completion of sensor processing and calibration (if performed), waits for next sensor input. Purpose: Determine mean processor utilization and mean and max cycle time for 1,000 cycles. “UAH1” computer Software exists

cs581 G. W. Cox -- Fall 2004 The University Of Alabama in Huntsville Computer Science Example SW/HW Model: SW i=1 to 10 Cal. Flag set Cal Processing Sensor input Y Process Sensor Data Part i Next i N 1000 FADD 2000 LD 2000 STO 500 FADD 500 FMULT 1000 STO

cs581 G. W. Cox -- Fall 2004 The University Of Alabama in Huntsville Computer Science Example SW/HW Model: HW UAH1 Computer performance: LD10 ns STO12 ns FAAD100 ns FMULT300 ns

cs581 G. W. Cox -- Fall 2004 The University Of Alabama in Huntsville Computer Science Example SW/HW Model: Simplifying the model i=1 to 10 Cal. Flag set Cal Processing Sensor input Y Process Sensor Data Part i Next i N 1000 FADD 2000 LD 2000 STO 500 FADD 500 FMULT 1000 STO Process Sensor data 10,000 FADD 20,000 LD 20,000 STO