Microcontroller and electronic control unit
View Patent ↗A microcontroller in which respective CPUs execute different applications so as to improve processing performance, and the respective CPUs execute an application that requires safety and mutually compare the results thereof so as to enhance the reliability of write data is provided. The microcontroller has a plurality of processing systems made up of a first CPU, a second CPU, a first memory and a second memory, and for the instruction processing about specific processing set in advance, the write to peripheral modules which are not multiplexed is executed twice, and the write data of the first time and the second time are mutually collated.
1. A microcontroller comprising a plurality of CPUs and a memory map register and carrying out control of an external device based on an instruction processing from the CPUs in accordance with data written to the memory map register, wherein
the memory map register has a register storing information about the number of writes of write data,
instruction processing about specific processing set in advance in the instruction processing from the CPUs is executed twice for the memory map register,
the two writes of the write data to the memory map register executed by the same instruction processing, each from different ones of the CPUs, and
a write data comparison circuit mutually collating the write data written twice to the memory map register is provided,
in each of the two write writes of the write data to the memory map register based on the same instruction processings from the different ones of the CPUs, write processing is executed only when a collation result in the write data comparison circuit is a match.
2. The microcontroller according to claim 1 , wherein
the memory map register is disposed in a peripheral module which carries out mutual transmissions of data for the control of the external device.
3. The microcontroller according to claim 2 , wherein
processing of mutually collating the write data written twice to the memory map register is carried out in the peripheral module.
4. The microcontroller according to claim 1 , wherein
the memory map register has a register storing information about the CPUs which have executed the write of the write data.
5. The microcontroller according to claim 1 , wherein
processing of mutually collating the write data written twice to the memory map register is carried out in a bridge which carries out access control of the memory map register.
6. An electronic control unit equipped with the microcontroller according to claim 1 , wherein
the control of the external device is carried out via an input/output interface connected to the microcontroller.