Abstract: A rotation-speed-calculation-apparatus includes: a detector configured to detect a rotation-angle of an engine; and a CPU and a memory coupled to the CPU. The CPU is configured to perform: calculating an engine-speed each time the detector detects a predetermined-angle based on a time-period required for the engine to rotate the predetermined-angle; and determining whether the engine-speed calculated is in a low-rotation range equal to or lower than a threshold-value or in a high-rotation range over the threshold-value. The CPU is configured to perform: the calculating including: calculating the engine-speed based on a time-period required for the engine to rotate a first-predetermined-angle when it is determined that the engine-speed is in the low-rotation range; and calculating the engine-speed based on a time-period required for the engine to rotate a second-predetermined-angle smaller than the first-predetermined-angle when it is determined that the engine-speed is in the high-rotation range.

Abstract: A communication control system includes: first/second control unit configured to control vehicle; first relay unit communicatively connected to the first control unit and having input unit to which data signal from diagnostic unit diagnosing state of the vehicle is input; second relay unit communicatively connected to the second control unit; first communication line communicatively connecting the first relay unit and the second relay unit; and second communication line disposed in parallel to the first communication line and communicatively connecting the first/second relay units. The data signal input to the first relay unit includes identification information. The first relay unit controls flow of data so that the data signal input to the first relay unit is transmitted through the second communication line when the data signal input to the first relay unit includes the identification information set to be communicated through the second communication line.

Abstract: A rotation-speed-calculation-apparatus includes: a detector configured to detect a rotation-angle of an engine; and a CPU and a memory coupled to the CPU. The CPU is configured to perform: calculating an engine-speed each time the detector detects a predetermined-angle based on a time-period required for the engine to rotate the predetermined-angle; and determining whether the engine-speed calculated is in a low-rotation range equal to or lower than a threshold-value or in a high-rotation range over the threshold-value. The CPU is configured to perform: the calculating including: calculating the engine-speed based on a time-period required for the engine to rotate a first-predetermined-angle when it is determined that the engine-speed is in the low-rotation range; and calculating the engine-speed based on a time-period required for the engine to rotate a second-predetermined-angle smaller than the first-predetermined-angle when it is determined that the engine-speed is in the high-rotation range.

Abstract: A control device is provided that can obtain high precision sensor outputs by way of a simple configuration without providing additional components. A control device 1 includes: an internal ground 24 and a power circuit 22, in which the internal ground 24 is divided into a high-power internal ground 241 provided inside of a housing 3 on a side of connection part 324, and a low-power internal ground 242 provided inside of the housing 3 at a position having an electrical distance from the connection part 324 that is farther than the ground 241. The ground of the control target 8 and the circuit 22 are connected to the ground 242, the ground of the sensor 6 is connected to a mounting part 325 having an electrical distance from the connection part 324 that is farther than the ground 241.