Use the USB to I/O port cable for spectrum ST4 to connect your spectrum to Dragonframe desktop software. This is a USB to a serial 3/32 TRS that goes from your mac or PC's USB port to the i/o port on spectrum. This cable allows spectrum to be controlled by dragonframe desktop software. This cable is a general purpose USB to Serial cable. Besides DragonFrame connections, it will allow developers to control the spectrum using the spectrum's API. The API is a work in progress. Reach out to firstname.lastname@example.org to gain access.