We have a Forth implementation that runs on TI MSP430 standard and ARM based PoSC's. Efforts are being made to finalize implementation on both the Cypress and Zilog ARM parts. TI, Cypress and Zilog provide an API to access the USB shim that controls the debug interface and serial comms to/from the target USB tether. Their IDE's access the target thru the same API - Each has a different API of course.
We seek info on what API is available for NXP tethered parts so we can port Forth here also.