----- Original Message ----- From: "Bob Axtell" > If I remember right, the Tiny bootloader makes no verification pass. > In a noisy environment, it is IMPERATIVE that the bootloader verify > that the data was actually written. The reason is that during the > flashing process, things are going on that can be disturbed by RF > noise, so tests must be made. As I mentioned to Tony, the Tiny Bootloader does do a crc check on the incoming block before it gets flashed in the PIC. My impression is that should give a high level of robustness that the data thus far is good. You say that things are going on during flashing that can be disturbed by RF. Could you elaborate? >From what I saw, it appeared after flashing that the program was running as it should the first few times that I powered up the device. I'm concluding that the PIC was flashed OK. It was only later things got strange. If RF noise was a big problem, I don't see it. I read 5 ADC channels and get dithering on the LSB of a 10 bit reading. The graphic LCD does not have any spurious things happening to it through the SPI connection. It is operating normally except for 2 special bitmap characters that are now messed up - but they are statically messed up not changing with every refresh. Gordon Williams -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist