ESCs can be easily attached to the PWM pins on the RoBonnet. However, there's a bit of software configuration necessary to make them useful.
Above shows the basic configuration of an ESC Part. The ESC can be configured to have a maximum forward and backward pulse width (in milliseconds) as well as a neutral range - this can vary depending on the ESC being used. In this example the ESC can drive the motor both forwards and backwards although different parameters can be set if the ESC is forward only. A toggle is also provided to switch the ESCs notion of forward and backward which can be useful if the attached motor is reversed (as can often be the case with two-wheeled robots). Finally, a direction change limit is provided. If you've ever tried slamming an ESC motor from forward to backward without going through neutral you'll know how bad an idea this can be (often causing the ESC to reboot or simply fail). This final setting limits how fast this change can be effected to prevent failure.
The "Setup" block shows how the ESC can be managed once configured. A velocity between -1 and 1 is translated by the ESC software into the appropriate motor motion based on the configuration. Here the motor velocity is just being set to zero which most ESCs require as part of their initialization.