Is it possible to get into ISP mode without switching the Vdd?

[antonbeerens]

No offense but to my opinion ISP and ICP (should?) mean something else.

ICP (In Circuit Programming): meaning you can program the processor without taking it off the board.
ISP (In System Programming): Meaning you can program the processor without taking it out of the system. And normally that automatically means that the processor does not require the Vdd to be switched on and off.

That NXP uses hardware and software for ISP ok but it could also be that you only need hardware. Like with the Silabs processors.

Again no offense but I like to discuss items like this. And my opnion is (not) always true


 

[Andy Ayre]

Well, the bottom line is that if you want to be able to be understood by other people using NXP devices, and you want to locate the right tools for programming NXP devices, you will need to use the NXP terminology.

Each silicon vendor uses different names for the concept of serial flash programming. I am simply giving you the NXP meanings as you are using NXP devices, not my personal opinion as that is irrelevant. Sorry.

Andy

[antonbeerens]

I understand, now lets hope I can remember it .

Thank you al for your support!

[Je Gold]

From within your code you can make a jump to to ISP boot loader. (Vdd is not powered off)

My very poor example code -  is available here http://www.flashmagictool.com/assets/resources/NoTouchLPC93x.zip

The Jump location address is different for different LPC900 micro's (usually based on the flash size).

Comment
To Jump to bootloader ISP mode -- 3 pulses on RESET  after POR are used.... this has the effect of setting the PC (program counter) to the Bootloader ISP address.


You can also write your own bootloader.

Joe

[erikm]

When programming fails it could be that the no touch code is not complete or the uart is not setup properly. In that case there is no way to reconnect to the processor anymore.

1) NoTouch was never intended for 'development' but for 'update by customer' Once your development is complete, the concerns you bring up should be irrelevant.
2) a 'factory freash' chip arrives in ISP mode, no pulses or other means is needed to program it
3) when using NoTouch for development, also include 'the backdoor'.  Of course this requires that the first upload (from 'factory fresh') is succesful. Quite a few use NoTouch/TheBackdoor for development.
4) I would have a few "easy cuts" on the PCB so, in case of several failures, an external jig could be made to switch Vdd and pulse reset.

Erik