LPC9**: ISP without VDD control

[Bernhard 'Gustl' Bauer]

Hi,

I have a HW which I want to program via ISP. I have RX, TX, Reset, GND and VDD on a connector.

The problem is I cannot let Flash Magic control VDD! So the programming works only whit a virgin LPC.

For reprogramming the idea is to keep Reset low until Flash Magic has initialized the serial ports. As I understand the manual there is only a minimum restriction (50

[erikm]

use NoTouch (found here)

Erik

[Bernhard 'Gustl' Bauer]

Hi,

if I understand notouch correct, I have to implement the notouch code into my code and execute it when an external stimuli happens. So the status bit ist set back to 1.  

I have several projects with LPC9** and most of them have all pins used. On most of them the serial IF is not used. So this stimuli can't be a break, or a port pin. Additionally I'd like to have one solution that fits all and not several different solutions. During debugging its not sure that notouch works on a stimuli.

So I'm looking for a different solution. I have set T1 and T2 to some 10 seconds. During this time I can switch the power of my hw off and on. Flash magic can now connect, even it has no control of VDD!  

Would it be possible to add a extention to flash magic? I should enable the user to switch off/on his HW after flash magic gains control over the serial IF. The user can confirm this hw reset via a klick.

Another possibility would be an adapter similar to the rs232 part of MBC900. With the extention of a XOR and a AND gatter. Those gatters could force reset to low if RTS==DTR.

What do you think of this?

Gustl

[erikm]

I have RX, TX, Reset, GND and VDD on a connector.

I have several projects with LPC9** and most of them have all pins used. On most of them the serial IF is not used.

those two statements do not jive


I have several projects with LPC9** and most of them have all pins used
one suggested method is to check TxD for low at bootup, that require no "extra pin"