A1 Pin output stuck Over voltage to the Short circuit in Observation High This assumes that – microchip LEDs Inspect pins, multiple pins are stuck at ‘1’ always off, overheated at ‘1’ invalid USB communication A2 Pin output stuck Under voltage to LEDs stuck on, Observation Low This could be 1 or more – at microchip, microchip fuel gauge does All LEDs stuck pins stuck at ‘0’ ‘0’ not turn on, on, probing pins “burned” out unable to control motors A3 Failure of A/D Chip defect, software Erratic movement Observation High – channel(s) malfunction, bad of the robot Robot does not reference lines, noisy move through power lines the maze correctly B1 Battery reading Rsense shorted, Cf Misinformation to Observation Low – discharging to shorted the user about the battery indicator quickly battery state drops quickly B2 Battery reading Rsense open circuited Thinks the battery Observation Low – not discharging is not robot is not discharging, no running power to board B3 Battery Cf open circuited, Misinformation to Observation Low – discharging at too R16/R17 open user about the Battery slow a rate circuited battery state discharges at an slower rate than reality
A1 Pin output stuck at ‘1’ Over voltage to the microchip Short circuit in LEDs always off, invalid USB communication Observation – Inspect pins, overheated High This assumes that multiple pins are stuck at ‘1’ A2 Pin output stuck at ‘0’ Under voltage to microchip, microchip “burned” out LEDs stuck on, fuel gauge does not turn on, unable to control motors Observation – All LEDs stuck on, probing pins Low This could be 1 or more pins stuck at ‘0’ A3 Failure of A/D channel(s) Chip defect, software malfunction, bad reference lines, noisy power lines Erratic movement of the robot Observation – Robot does not move through the maze correctly High B1 Battery reading discharging to quickly Rsense shorted, Cf shorted Misinformation to the user about the battery state Observation – battery indicator drops quickly Low B2 Battery reading not discharging Rsense open circuited Thinks the battery is not discharging, no power to board Observation – robot is not running Low B3 Battery discharging at too slow a rate Cf open circuited, R16/R17 open circuited Misinformation to user about the battery state Observation – Battery discharges at an slower rate than reality Low
hw11_grp7.docx