Lpc2000

Jim Beagley wrote:

> Brian,
>   The experience I have had with the secondary JTAG port has led me to
> these conclusions:
> 
>   A) Put 2 headers on your board, 1 for the Primary, and 1 for the
> Secondary connections.
>   B) The following connections are required:
>       - 3.3v (i/o voltage)(wiggler may not require)
>       - TRST
>       - TDI
>       - TMS
>       - TCK
>       - RTCK
>       - TDO
>       - GND
>   C) Jumper on DBGSEL ( High for Primary, Low for Secondary )
>   D) PIN 44 pulled high on startup ( if low, debug mode for serial
> will be entered)
> 
> I am using the NOHAU USB pod, and it requires the 3.3v. It also has a
> problem connecting directly to the Secondary port, the following
> procedure is required:
>  - connect using the primary port, switch to secondary, and reset the
> debugger. ( this may be unique to NOHAU's SEEHAU debugger )
> 
> Also, I have had no success programming with the secondary port. I use
> the primary to program, and secondary to debug.
> 
> Good luck.

Thanks for the great info! Having JTAG 2 ports in the design would make 
using the 2106 impossible (we really need all those pins). Has anyone 
had similar experiences? Or better yet, has anyone successfully used the 
second JTAG port for debug and programming?

Also, we are seriously looking at the LPC2124 instead, and it looks like 
it only has 1 JTAG port on it, so I'd assume that this wouldn't be a 
problem.

Thanks,

Brian
-- 
-----------------------------------------------------
Brian C. Lane (W7BCL)                      Programmer
www.shinemicro.com   RF, DSP & Microcontroller Design