I am not familiar with Erik's infamous version for the Philips parts, so I am not sure if this is really No-Touch. My application software sets a flag to set up the ISP mode. I accomplish that by grounding a port pin.

That would be 'the backdoor'. To implement 'NoTouch", you will see in the NoTouch description that to achieve NoTouch you activate (in your case : software sets a flag to set up the ISP mode) when e.g. a certain string is received through the serial port. For other suggestions, see NoTouch document.

Erik

PS infamous ???