Didn't ROM chips have fusible links for programming years ago? Is it all manufacturers or just Microchip that uses EPROM parts without windows for ROM? (I realize ROM is a misnomer since there's also a CPU but you get the idea) thanks chuckc -------Original Message------- From: Lee Jones Sent: 05/03/03 03:46 AM To: PICLIST@MITVMA.MIT.EDU Subject: Re: [PIC]: Programming OTP devices? > > > Curious ... I haven't used, nor seen any reference to programmers > for OTP devices. I guess UV is needed to erase, but what about > programming? Programming, and programmers, are identical. An OTP (One Time Programmable) device is the UV-erasable die in a less expensive, non-windowed package. It's ready to program. Since there's no way to erase it (*), it can be programmed once. The same die, when mounted in a more expensive ceramic package with a UV-transparent window, becomes a multiple-use erasable and reprogramable part. Lee Jones (*) occasionally there are threads on the PIC list about using X-rays (see friendly dentist) to erase OTP devices instead of buying the more expensive reusable, windowed devices. -- http://www.piclist.com hint: The list server can filter out subtopics (like ads or off topics) for you. See http://www.piclist.com/#topics > -- http://www.piclist.com hint: The list server can filter out subtopics (like ads or off topics) for you. See http://www.piclist.com/#topics