I am currently, like many other trying to devise a way to do high speed ADC sampling (based on the internal ADC) using the usb to stream data back to the PC. Does anyone have any suggestions, particularly with regards to using USB to achieve high data rates? Or even better has anyone got any sample code for something similar? My current thinking is to use an internal timer to sample the data as required, and buffer this either internally or store it in an external memory, then to upload the data in batches using ping-pong buffering. Does anyone have any experience with ping-pong, and can the microchip firmware be easily modified to support it?? Many Thanks, Mat www.piccoder.co.uk -Basic USB and Networking PIC Article's and discussion. -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist