| 摘要 |
PURPOSE:To make a sharp distinction of a faulty area between a sensor of an input part and an A/D converter by deciding whether the digital data output of the input part of a microcomputer is all ''0'' or ''1'' and out of a prescribed range or not. CONSTITUTION:An analog signal A given from a sensor 2 is converted into the digital data D by an A/D converter 4 with a switch signal C given from a control part 3. The data D is sent to a bus line 5 to undergo a desired control operation through a control arithmetic part 6. The 1st discriminating part 7 decides whether the value of the data D is all ''0'' or ''1''. Then the 2nd discriminating part 8 decides whether the value of the data D is smaller than the prescribed 1st discrimination value M1 larger than all ''0'' or larger than the prescribed 2nd discrimination value M2 smaller than all ''1''. Both discrimination data Da and Db decide a fault of the converter 4 in case the contents of the digital data are equal to all ''0'' or ''1'' and then a level fault of the analog signal if the contents of the digital data are equal to the value other than the values M1 and M2 through a diagnosis part 9. |
