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Dear all,
i want to change the bootloader of 89v51rd2 so i had gone to isp->update bootloader and then
given updated file name and press update.
i could able to update one microcontroller but when i tried with other microcontroller(89v51rd2)
it stopped in erasing part and not able to come out of it.
now i couldn't put microcontroller in isp mode nor i could able to put it into execution mode.
even after resetting it's not getting programmed

is it possible to program more than one microprocessor using production system?
if yes than how,
as we require to program more UC in less time.
regards
MKD