Today, the OBD diagnostic chips are increasingly based on CAN-processor platform, and so in May to change the data in different ways by the scanning protocol. PING protocol ‘sequentially The diagnostic chip “and ties up the system management engine when the correct protocol is recognized. The 8-bit PIC or AVR used as hardware platform is, however, but requires much additional hardware to meet the needs of all multiple protocols. It’s time for a better solution using a modern controller is the motivation for the synthesis module Diamex DXM, used in our BY OBD2 Scan.
The module includes an ARM Cortex M3 DXM controller and the necessary surfacemount device (SMD) circuit on a small printed circuit board (PCB). This plugin allows to reduce circuit requirements for a minimum and provides a material basis for a unified yet flexible development projects OBD2 compact. Designed as a universal OBD2 diagnostic and control unit with its own dedicated firmware, it can be connected directly to the diagnostic port of a vehicle. At high speed (up to 250,000 baud) serial interface allows an external connection. At the heart of this module is the 32-bit ARM Cortex M3 CPU with a clock frequency of 72 MHz, 64 KB of Flash memory and 20 KB of RAM. The environment includes protection of online K IC, a driver may MOS transistors for the PWM-based protocols, two signal lines and a dedicated power supply with overvoltage protection.
