In addition to the on-chip hardware safety features, the self-test CPU software makes it easier for manufacturers of industrial, motor control and home appliances to meet IEC60730-1 (IEC60335) class B safety requirements. The safety standard requires software running on an MCU to be able to detect any safety critical failures according to specific fault models. This software offers high value to any firmware developers involved in safety critical applications and appliances because the VDE approved software is suitable for all of Renesas’ RX200 microcontrollers, said Vincent Mignard, Renesas’ global marketing leader for Home and Small Appliances.
The RX200 MCU family integrates on-chip key advanced peripherals like the cyclic redundancy check engine, while the analogue/digital converter includes a self-diagnosis function – to ensure plausibility checks – and a hardware clock monitoring function. Finally, the RX200 offers the unique Data Operating Circuit module which reduces the RAM March X algorithms testing time and frees up the overall CPU load.
Renesas’ self-test software has been successfully certified for its periodic test routines for CPU registers and program counter test, stack test, RAM tests (using March X & C algorithms), Flash check (using cyclic redundancy check engines) and clock monitoring tests. These routines are easy to integrate in any existing software and can be called after Reset and periodically during run-time. The software enables the developer to easily design safety relevant software and to meet certification requirements quickly and with less effort. It can reduce development time and the test harness process by up to 3 months, and the cost of certification by 15%.