Shield Case:
You can put your Electronics-PCB in the metal box. This is good way to protect your PCB from various kindsof direct electrical noises. Actually, at the automobile industry, the main PCB, like as the Engine control, is set in the think metal case. However, it is the electronics PCB, there are many wires as the inputs, outputs and the power supplied. Thus, the electrionics-PCB may induce many kinds of noises via these wire connections. |
Watch-Dog:
It is the common sense to use the watchdog-timer as for the system recovery purpose. Almost all Micro is equipped this Watchdog-timer and if there is no tick to the counter time, it generatessystem RESET and make the Micro restart. This Watchdog timer is still important even though your hired our "High Resilience System" since manyCPU, like ARM M series, A series, R series, old Motorola MC68000 series, there is a function, CPU halt,and once athe CPU fallin this CPU halt, there is no other way to recover CPU. This watchdog timer is the Last method in our Resilience system. The other hand, the watchdog timer may cause serious problem when it shall makes system restart. If the applicatrion is using the motor driver, like as PWM for the motor speed controle. The PWM shall be reset also and the motor speed direction is certain several RPM to sudden stop. Depend on the motor size and speed, this sudden stop may cause physical dameges and/or accidents. Take care if you shall use the Micro equipped timers for motor speed controle. |
Self-Diagnostics at Operating System CPU design:
As same as many home appliances, Automobile equipments, measurement tools, you can make your owndiagnostics for your system. Depending on the system, what shall be subject of the self-test shall be different. One example, If the Micro has Ethernet, Wifi, UART and other communication port, there should be thecheck of data transfer volume, how many bytes are transmitted and received. If the data transfer volume is zero, it may mean that the system may be a part of system is malfunction. |
CPU design:
If you are using a FPGA, you can choice many CPU design. At the CPU selection, you should hire a CPU, asynchronous one, since there are small timing slot to receivethe noises. And also, you should set the memory data recovery, a parity plus extended bits. The data error can be detected by the data error collection system and it can reduce the possibility that theCPU may read the error data. |
| r | MMU, MPU:
MMU is a Memory management and MPU is a Memory protection unit. Both are hardwaere on the same silicon die of the CPU. By these function, the system can detect abnormal memory access and in many cases, it is the malfunctionof the CPU. |