Content originally posted in LPCWare by ArneB on Thu Jan 15 08:16:05 MST 2015 For the archive and anyone, who might have troubles re-invoking the ISP mode on the LPC824:
Don't forget to disable your DMA controller, if you are executing the "re-invoke ISP" IAP command !
Otherwise the bootloader and the still active DMA controller are fighting for the incoming UART bytes, resulting in a non-working ISP mode.