Re: [avr-chat] Dragon: mega slow at dumping Flash, normal ?

[Daniel O'Connor]

On Mon, 29 Jun 2009, Vincent Trouilliez wrote:
> Thanks Daniel and Roger !
>
> I have now my anwser... even if not a pleasing one.
>
> Geez, I bought a USB programmer and Dragon, thinking it would be way
> faster than my antic // cable... only to find out it's exactly the
> opposite ! How ironic, antic interfaces that smoke circles around
> modern ones ! Likewise, me thinks the old serial port is unlikeley to
> die anytime soon then...

If you use it the right way it IS faster.

USB, like PCIe and other busses is a high latency high throughput thing.

FIFO memory is cheap and allows faster performance with less 
synchronisation which is good when you have a lot of cores :)

> Oh well, I will just put my Dragon in a drawer and use my // cable
> again. I will just need to buy an extra // interface card for my
> computer (because my printer is on the // port too, and I got tired
> of swapping all the time, one of the reasons I wanted USB !), but I
> doubt it will cost me more than this door stop of a dragon ! Hell no,
> even as a door stop it's no use ! ;-/
> Well, lesson learned... newer, shinier and more expensive is not
> always better or even as good... far from that.

I don't understand why you don't use -U?
It is just as fast as the old parallel cable I use but saves a bunch of 
CPU time (not that it is a big issue). I am using it in ISP mode, I 
have used it in JTAG mode too, but most recently I was updating 
firmware on a board which didn't have JTAG, it worked just fine.

-- 
Daniel O'Connor software and network engineer
for Genesis Software - http://www.gsoft.com.au
"The nice thing about standards is that there
are so many of them to choose from."
  -- Andrew Tanenbaum
GPG Fingerprint - 5596 B766 97C0 0E94 4347 295E E593 DC20 7B3F CE8C

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