Re: [avr-gcc-list] OCDEN Fuse

[Armand ten Doesschate]

On Fri, Nov 25, 2005 at 02:55:20PM -0700, Gary Douglas wrote:
> I'm sure it does, but I'm trying to figure out the application of it. 
> The datasheet is clear, but doesn't provide an explanation of the 
> advantage of using it.
> 
> Does AVR Studio's debugger have enhanced functionality as a result of 
> enabling OCD - or is it just a magic extra register (with some 
> notification ability) to use at will?
> 

<snip>

When the jtag ice boxes stopped succesfully the target during a debugger
session, then the target is to be in a so called debugging state. Only during
this debugging state the OCDR will be visible and the avr core will exchange
data with the jtag ice boxes. When the jtag ice boxes terminate this debugging
state then they can / will disable the OCDEN fuse bit.

AVR studio debugger doesnot know anything about this debugging state as
this will be managed only by the jtag ice boxes.
This also means that during a running application the OCDR isnot visible.

Armand

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Armand ten Doesschate
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