Lpc2000

--- In lpc2100@yahoogroups.com, "Brian C. Lane" <brian@s...> wrote:
> Leon Heller wrote:
> 
> > ----- Original Message ----- 
> > From: "martin de lange" <martin_de_lange@x...>
> > To: <lpc2100@yahoogroups.com>
> > Sent: Tuesday, February 03, 2004 8:23 AM
> > Subject: Re: [lpc2100] JTAG port
> > 
> > 
> > 
> >>Do you mean that one would sometimes use the one JTAG port and 
at other
> >>times use the other accoording to which I/O you wanted to use ?
> > 
> > 
> > Yes, it's mentioned in the data sheet.
> > 
> > 
> >>I have also seen at times that users at times cannot get the 
second port
> > 
> > to
> > 
> >>work for debug and or flashing.
> > 
> > 
> > I think that Philips has stated that the second JTAG port cannot 
be used for
> > programming, only debug.
> > 
> 
> Where? That's a pretty important piece of info. If that's the case 
then 
> this part isn't as useful as it looks at first glance. If you need 
the 
> primary JTAG for debug and programming then you lose those pins 
and the 
> trace pins (from my understanding).
> 
> Sharing JTAG pins with I/O is an understandable practice from the 
> manufacturer's standpoint, but from mine it makes designing things 
alot 
> more difficult -- its pretty hard to assign any useful function to 
the 
> pins that are used by the JTAG. You're almost better off 
programming it 
> via the serial port and using 1-line diagnostics to debug like you 
have 
> to do on the PIC <G>.
> 
> Brian
> 
> 

Hi Brian !

And how about programming it using the serial port and debugging 
with the secondary JTAG ? It is possible?

Juanjo