2 kasamiko: I had no problems with reading or writing used AtMega8 flashed to
use external clock generator(12 MHz). Bought a new chip and flashed it, then I
have find better firmware for my device(with corrections and russian
translation). Successfully read current firmware and write a new one without
any errors... So maybe you had used wrong socket?
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Need help with flashing brand new(clear) AT89S51. Tried all combinations in
device list and have no success.
2 kasamiko: I had no problems with reading or writing used AtMega8 flashed to
use external clock generator(12 MHz). Bought a new chip and flashed it, then I
have find better firmware for my device(with corrections and russian
translation). Successfully read current firmware and write a new one without
any errors... So maybe you had used wrong socket?
89S51 is not supported.
You have to modify source code to program it.