Versatile top board for MPC55xx-based VertiCal architecture

• Off-the-shelf top board for MPC55xx VertiCal base boards from Freescale
• DPMEM bypass interface with minimal communication latencies
• Additional SRAM for calibration data
• On-board JTAG/Nexus connector for calibration, measurement, or debugging
• VertiCal connector to add further top boards

Application Areas
Control algorithms for electronic control units (ECUs) in modern vehicles can be developed and optimized efficiently by the external bypassing method. This involves calculating selected ECU functions on powerful and flexible prototyping hardware (e.g., MicroAutoBox or AutoBox), while the remainder of the code continues to run, unmodified, on the existing ECU. The DS541 serves as an ECU interface for function bypassing using the integrated dual-port memory (DPMEM) and the high-speed LVDS interface to the external prototyping system. In addition, the DS541 supports ECU calibration, and it provides an interface for ECU debugging or flash programming.

Key Benefits
The DS541 minimizes communication latencies between the prototyping hardware and the electronic control unit (ECU). This makes it ideal for bypassing ECU functions that require fast execution rates and a large number of model inputs and outputs. The DS541 is a top board for MPC55xx VertiCal Base Boards from Freescale, which can be connected to the ECU simply by installing a base board in place of the ECU’s original microcontroller. Low latencies, combined with high signal integrity, are achieved by several factors: direct access to the microcontroller bus via the VertiCal connector, very short signal line lengths between the dual-port memory and the MPC55xx, and a fast LVDS interface. The available Simulink blocksets support two variants of external bypassing: address-based and service-based bypassing. The DS541's additional SRAM allows the POD to be used as a memory for calibration data. If the POD’s voltage supply is connected to the vehicle battery, the SRAM data is retained after the ECU is switched off. As a calibration interface, for example, the ECU's CAN bus or the JTAG/Nexus interface available on the DS541 itself can be used. The DS541’s VertiCal connector allows further plug-on boards to be connected, for example, for memory emulation.