The CMX-USB suite offers an optional OTG (On-The-Go) Module for applications whereby two devices must negotiate and decide which will act as a USB Host and which will operate as a USB device. The CMX-USB-OTG module is available for those processors which are equipped with an OTG controller that supports the HNP and SRP protocols which are used for USB host and USB device negotiation.

More often, embedded applications that require both USB host and USB device capability require dual mode operation. In dual mode, when a USB host is inserted, the host stack will start and when a USB device is inserted, the device stack will respond. This is accomplished by recognition of the ID pin on the USB OTG connector and is supported by CMX USB host and device stacks. For dual mode operation, OTG software is not required.