For C2000, ARM Cortex M3, and STM32 devices, Embed uses a JTAG HotLink to communicate data between the host and the target device. For Arduino devices, Embed uses a serial HotLink. And for Linux devices, Embed uses an Ethernet or Wi-Fi HotLink.
The HotLinks support both normal and high-speed data collection. In normal mode, commands are sent from the host to the target and data is collected from the target for the host. The signal transfer rate is limited to approximately 200 words/sec.
During the PIL and HIL phases, data must be acquired at a much faster rate. For example, you will have to record data at the frequency that the control algorithm is running at, which could be 10kHz or greater. Embed provides the Monitor Buffer Read and Monitor Buffer Write blocks (for all targets except Arduino, Linux, and MSP430) that execute over the HotLink specifically for this purpose. The monitor buffer provides a mechanism for a debug diagram to buffer a large volume of data acquired on the target at the target’s native sample rate, transmit the data periodically over the slower HotLink from the target to the host, and then make the buffer contents available as a vector of data on the host application. The monitor buffer shown below uses the buffer mechanism to capture and transmit a buffer of 1001 elements collected at 10,000Hz from the target. The host, running at 100Hz, then plots the sample values much like a triggered oscilloscope trace.