Program Overlay Mechanism for Engine Control Module Delphi South America Technical Center - Brazil

Format:

Conference/Event

Author/Creator:

Cruz, Cruz, author.

Contributor:

Filho, Orlando Volpato

Conference Name:

SAE Brasil 2010 Congress and Exhibit (2010-10-05 : Sao Paulo, Brazil)

Language:

English

Physical Description:

1 online resource

Place of Publication:

Warrendale, PA SAE International 2010

Summary:

As the complexity and size of algorithms dedicated to EMScontinually grows more hardware resources, like processing speedand memory are demanded, increasing the cost of the final product(ECUs in this case). This paper presents a technique aimed atsaving flash memory space by pulling pieces of executable binarycode out of the microprocessor's flash area and storing them inan external device like an EEPROM. When the application needs toexecute that piece of code stored at EEPROM, it will request it tobe downloaded into an available RAM memory area and run it fromthere. For such it is required that some sort of allocationtechnique be applied once the RAM size is by far much smaller thanthe EEPROM storage device's size meaning that the whole contentof EEPROM cannot be downloaded single shot into RAM. It happens tobe necessary a strategy to break the flash application code down insmaller pieces to be stored at EEPROM.This technique can be summarized in 6 steps:Software development at the host platform phase: 1. Provide astrategy to decide what part of the current implementation is worthto be moved to EEPROM. 2. Separate that part of code by redesigningand refactoring the current application. 3. Compile and link thatcode so it can be separately stored at EEPROM.Software running at the target platform phase: 4. Check if thecode has been already downloaded in to RAM. 5. If not, look up theRAM and find a free space to house the code. 6. Download the codefrom EEPROM to RAM. 7. Execute it in RAM.This algorithm is an alternative approach to the very well knownindustry standard memory managers base on the implementations of"Best Fit," "Worst Fit," "SequentialFit," as well as the combination of them

Notes:

Vendor supplied data

Publisher Number:

2010-36-0157

Access Restriction:

Restricted for use by site license