ISP on LPC936

Started by Sutton Mehaffey February 5, 2009
Anyone done ISP on a 936?

On the app. note AN10258, there is a statement that says 'To control
VDD, a PNP transistor is needed, because P2.3 cannot supply enough
current for the LPC9xx during programming.'

Can I just supply 3.3V all the time to the 936 and not connect P2.3 to
my board? Problems with that?

Sutton

--- In l..., "Sutton Mehaffey"
wrote:
>
> Anyone done ISP on a 936?
>
> On the app. note AN10258, there is a statement that says 'To control
> VDD, a PNP transistor is needed, because P2.3 cannot supply enough
> current for the LPC9xx during programming.'
>
> Can I just supply 3.3V all the time to the 936 and not connect P2.3
to
> my board? Problems with that?
>
> Sutton
>
No, you must build it as stated, it is part of the timing for
entering setup to the device. Build it exactly like the app note and
it will work 100%........yes I'm using the 936 and have built a
programmer for both ISP and ICP.

The programming board actually provides power to the application at
specific times and not at other times???

--- In l..., "kittmaster" wrote:
>
> --- In l..., "Sutton Mehaffey"
> wrote:
> >
> > Anyone done ISP on a 936?
> >
> > On the app. note AN10258, there is a statement that says 'To control
> > VDD, a PNP transistor is needed, because P2.3 cannot supply enough
> > current for the LPC9xx during programming.'
> >
> > Can I just supply 3.3V all the time to the 936 and not connect P2.3
> to
> > my board? Problems with that?
> >
> > Sutton
> >
> No, you must build it as stated, it is part of the timing for
> entering setup to the device. Build it exactly like the app note and
> it will work 100%........yes I'm using the 936 and have built a
> programmer for both ISP and ICP.
>

--- In l..., "Sutton Mehaffey"
wrote:
>
> The programming board actually provides power to the application at
> specific times and not at other times???
>
> --- In l..., "kittmaster" wrote:
> >
> > --- In l..., "Sutton Mehaffey"
> > wrote:
> > >
> > > Anyone done ISP on a 936?
> > >
> > > On the app. note AN10258, there is a statement that says 'To
control
> > > VDD, a PNP transistor is needed, because P2.3 cannot supply
enough
> > > current for the LPC9xx during programming.'
> > >
> > > Can I just supply 3.3V all the time to the 936 and not connect
P2.3
> > to
> > > my board? Problems with that?
> > >
> > > Sutton
> > >
> >
> >
> > No, you must build it as stated, it is part of the timing for
> > entering setup to the device. Build it exactly like the app note
and
> > it will work 100%........yes I'm using the 936 and have built a
> > programmer for both ISP and ICP.
> I've seen it do that, I guess the logic is that it can do an ISP
without the system power on. I've seen it light up my target board
led, program, then disable power....

I figured that was what the logic was. I was trying to see if it was
mandatory.

Thanks.

--- In l..., "kittmaster" wrote:
>
> --- In l..., "Sutton Mehaffey"
> wrote:
> >
> > The programming board actually provides power to the application at
> > specific times and not at other times???
> >
> >
> >
> > --- In l..., "kittmaster" wrote:
> > >
> > > --- In l..., "Sutton Mehaffey"
> > > wrote:
> > > >
> > > > Anyone done ISP on a 936?
> > > >
> > > > On the app. note AN10258, there is a statement that says 'To
> control
> > > > VDD, a PNP transistor is needed, because P2.3 cannot supply
> enough
> > > > current for the LPC9xx during programming.'
> > > >
> > > > Can I just supply 3.3V all the time to the 936 and not connect
> P2.3
> > > to
> > > > my board? Problems with that?
> > > >
> > > > Sutton
> > > >
> > >
> > >
> > > No, you must build it as stated, it is part of the timing for
> > > entering setup to the device. Build it exactly like the app note
> and
> > > it will work 100%........yes I'm using the 936 and have built a
> > > programmer for both ISP and ICP.
> > >
> >
> I've seen it do that, I guess the logic is that it can do an ISP
> without the system power on. I've seen it light up my target board
> led, program, then disable power....
>