ISP works only first time for LPC2103 and LPC2148

[aaag_3]

hello,
      i have been trying ISP for LPC2103 and LPC2148 . The ISP works only for the first time for downloading the code. the secong time onwards the autobaud fails. I have not changed any of the flash magic settings....Also some of my friends in other firms have similar experiance.....Can any one please tell me the solution for this? Or where am i going wrong?
thank you,
amit

[Andy Ayre]

Put a scope on the reset pin and the ISP entry pin. Attempt to place the device into ISP mode. Do the waveforms on your scope match the requirements in the datasheet/user manual? If not in what way do they differ?

Andy