Re: [ECOS] ethernet download

[Grant Edwards <grante at visi dot com>]

On Fri, Aug 24, 2001 at 09:59:25AM -0600, Gary Thomas wrote:
>
> >> How about hardware with no serial port - only an ethernet
> >> connection? Yes, we have worked with such beasties... fun, in
> >> the purest sense :-)
> > 
> > My version of RedBoot listens on a TCP port.  You push the
> > reset button then you've got 10 seconds to telnet to RedBoot.
> > Once you've opened a telnet session, it just like you're
> > connected to a serial console.
> 
> Actually, they all work that way :-) The real problem is when
> you're just bringing things up initially (or making major
> changes to the startup code).  Trying to debug with only a
> network connection in this environment can be more than tricky.

That's when you use hardware-assisted debugging: either a
full-up in-circuit emulator or something like a JTAG interface.
Wasting several weeks of engineering time (and marketing
window) to save a few thousand dollars is false economy.

Or layout the board with a debugging serial port (something
with a nice big FIFO that will run at 115K baud or higher) and
then don't populate that portion of the board in production.

Or put a header of some sort on the board so that you can
attach a daughterboard with a UART.  Something as simple as a
three pin SPI or I2C connector can be used to interface to a
UART while you're debugging.

-- 
Grant Edwards
grante@visi.com