Search Results

The Brazilian automotive market is growing, vehicle sales ranked in the 4th. global position only behind China, United States and Japan; more than 40% of Brazilian production are entry level vehicles. The use of air conditioning systems in those basic vehicles are increasing due to being also considered as a safety device, besides its original thermal comfort function. Since 2008 a partnership between Inmetro, CONPET and Petrobras established the adoption of an “energy seal” ranking of vehicles in respect to their fuel consumption; the newly introduced tax regime: Inovar-Auto establishes less taxation to more efficient vehicles. This and other environmental concerns are demanding the reduction of CO2 emissions. Due to cost restrictions, the A/C systems installed in those vehicles, in most of the cases, are too simple and inefficient.

As the complexity and size of algorithms dedicated to EMS continually grows more hardware resources, like processing speed and memory are demanded, increasing the cost of the final product (ECUs in this case). This paper presents a technique aimed at saving flash memory space by pulling pieces of executable binary code out of the microprocessor's flash area and storing them in an external device like an EEPROM. When the application needs to execute that piece of code stored at EEPROM, it will request it to be downloaded into an available RAM memory area and run it from there. For such it is required that some sort of allocation technique be applied once the RAM size is by far much smaller than the EEPROM storage device's size meaning that the whole content of EEPROM cannot be downloaded single shot into RAM. It happens to be necessary a strategy to break the flash application code down in smaller pieces to be stored at EEPROM.