On 3/11/06, Spehro Pefhany wrote: > I don't think there is any nonvolatile code memory to protect on those > chips. Ah...I misunderstood the datasheet. Seems you have a choice with this chip - you can download the program each time via USB or store it on a serial EEPROM chip. That's somewhat intriguing...but doesn't that mean that there is no way to prevent someone from copying your device? If the code is stored in an external EEPROM, there is no way to block someone from reading it, and if you download the code each time, then you can simply copy the circuit as there really isn't any programming in the device. Right? Josh -- A common mistake that people make when trying to design something completely foolproof is to underestimate the ingenuity of complete fools. -Douglas Adams -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist