Application Areas
For processor bus architectures with less external or off-chip visibility, dSPACE provides a generic serial interface (GSI) which supports different on-chip debug ports for measurement, calibration, and bypassing. Adaptation to a specific electronic control unit (ECU) can be done via an individual connector adapter and a firmware update on the DCI-GSI1.
Operation Modes
For measurement, the DCI-GSI1 supports two strategies: with ECU service (data aquisition is triggered by a small piece of code included in the ECU code) and without ECU service (data aquisition is triggered by an ECU event). For example, data capturing can be triggered via digitial I/O pins of the microcontroller or by the GSI, which is capable of detecting write accesses to specific ECU memory addresses. In addition, it is also possible to perform measurements according to the GSI‘s on-board timer. To calibrate ECU parameters, the DCI-GSI1 supports both overlay units that are provided by the ECU´s microcontroller and an external RAM for the calibration data. During bypassing, the DCI-GSI1 performs the data transfer and triggers the bypass system, which calculates the controller function outside the ECU. If bypass, calibration, or measurement accesses to the ECU are requested at exactly the same time, the GSI gives bypass access the highest priority. This way, minimal latencies in communication between the ECU and the prototyping system are always guaranteed without compromising the measurement bandwidth.