[ECOS] Programming flash?

[ECOS] Programming flash?

[Paul Pham]

Hi all,

My team and I are designing a board around the Samsung S3C3410x, based on
the ARM7TDMI, booting off Flash memory. Does anyone have any recommendations
for ways to program Flash with only one serial port?

Also, does anyone know if the S3C3410x is little-endian or big-endian? I
believe the ARM7 is little-endian by default, and there is a big-endian pin
on the processor core that determines whether it is big-endian or
little-endian. Unfortunately, I can't find which it is in the Samsung
documentation.

Many thanks,
Paul

Re: [ECOS] Programming flash?

[Lewin A.R.W. Edwards]

Hello Paul,

>My team and I are designing a board around the Samsung S3C3410x, based on
>the ARM7TDMI, booting off Flash memory. Does anyone have any 
>recommendations for ways to program Flash with only one serial port?

Load the flasher program into RAM, and run the upgrade out of RAM using 
polled serial I/O to avoid annoyance and complications with interrupt tables.

>Also, does anyone know if the S3C3410x is little-endian or big-endian? I
>believe the ARM7 is little-endian by default, and there is a big-endian pin
>on the processor core that determines whether it is big-endian or
>little-endian. Unfortunately, I can't find which it is in the Samsung
>documentation.

If you can't find a pin that is documented to have this behavior, then that 
connection point on the core is probably tied internally and not brought 
out to a pin.

=== Lewin A.R.W. Edwards (Embedded Engineer)
Work: http://www.digi-frame.com/
Personal: http://www.zws.com/ and http://www.larwe.com/

"Und setzet ihr nicht das Leben ein,
Nie wird euch das Leben gewonnen sein."

Re: [ECOS] Programming flash?

[Grant Edwards]

On Wed, Jan 24, 2001 at 10:06:19PM -0500, Paul Pham wrote:

> My team and I are designing a board around the Samsung
> S3C3410x, based on the ARM7TDMI, booting off Flash memory. Does
> anyone have any recommendations for ways to program Flash with
> only one serial port?

Assuming you've got working code in the flash to start with
(!), one generally downloads an application into RAM that burns
the flash.

> Also, does anyone know if the S3C3410x is little-endian or
> big-endian? 

The CPU will operate in either big-endian or little-endian
mode.  The external memory interface will operate in either big
or little endian mode.  However, the internal registers and
peripherals are hooked up for big-endian mode.

See page 4-1 in the users manual.

In older versions of the part external memory worked only in
big-endian mode. But in the current parts, external memory will
work either way -- but it's sort of moot since internal
peripherals are big-endian.

-- 
Grant Edwards
grante@visi.com

Re: [ECOS] Programming flash?

[Grant Edwards]

> >Also, does anyone know if the S3C3410x is little-endian or big-endian? I
> >believe the ARM7 is little-endian by default, and there is a big-endian pin
> >on the processor core that determines whether it is big-endian or
> >little-endian. Unfortunately, I can't find which it is in the Samsung
> >documentation.
> 
> If you can't find a pin that is documented to have this behavior, then that 
> connection point on the core is probably tied internally and not brought 
> out to a pin.

It's pin 49 (LITTLE).  It needs to be tied low to operate in
big-endian mode.

-- 
Grant Edwards
grante@visi.com