SDRAM testing

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Bob

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Jul 14, 2010, 5:21:23 PM7/14/10
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I have now got the SDRAM test working better and discovered 1 or 2
bugs in our setup code, probably down to the manual being pretty
confusing. The test does a sequential write of the RAM to 32MB ok, I
will look at more extended tests tomorrow.

I have a problem with my Windows setup, which is that I have no decent
tools to write to an SDcard under windows, so I have been using JTAG
to load code. I have found a windows version of dd, but need to make
sure it is reliable before writing to random partitions! I could also
do with a proper fdisk tool.

The rockbox bootloader is quite simple, it loads the main code from a
FAT32 partition on the SD into RAM. That might even fit into 16K, so
we would not need a second stage bootloader. That doesn't help the
Unix booting but maybe we address that later. I don't really know much
about Unix boot up anyway, the Chumby bootloader looks pretty
horrible, it has a whole bunch of text strings so it can pass
parameters to a Unix command line.

Casainho

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Jul 14, 2010, 6:32:57 PM7/14/10
to rockbo...@googlegroups.com
On Wed, Jul 14, 2010 at 10:21 PM, Bob <bobcou...@googlemail.com> wrote:
I have now got the SDRAM test working better and discovered 1 or 2
bugs in our setup code, probably down to the manual being pretty
confusing. The test does a sequential write of the RAM to 32MB ok, I
will look at more extended tests tomorrow.

Nice!
 
 
I have a problem with my Windows setup, which is that I have no decent
tools to write to an SDcard under windows, so I have been using JTAG
to load code. I have found a windows version of dd, but need to make
sure it is reliable before writing to random partitions! I could also
do with a proper fdisk tool.

Linux a better solution? ;-)
 
 
The rockbox bootloader is quite simple, it loads the main code from a
FAT32 partition on the SD into RAM. That might even fit into 16K, so
we would not need a second stage bootloader. That doesn't help the
Unix booting but maybe we address that later. I don't really know much
about Unix boot up anyway, the Chumby bootloader looks pretty
horrible, it has a whole bunch of text strings so it can pass
parameters to a Unix command line.

I vote for a simple Rockbox bootloader, let's forget Linux boot option for now.

thomaslloyd

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Jul 15, 2010, 2:38:30 PM7/15/10
to rockboxplayer
Hi Bob,


For windows try using cygwin, this can be installed on a usb stick
with a bit of tweaking making it portable in Windows Linux solution.
It comes with all the normal Linux tools. When i was working on the
project a few years ago I found that having an old machine with com
ports etc etc running Linux connected to all the development kit was
really useful. Then I would ssh into that machine and work from my
Windows machine.

I think that cygwin will do most of what you want as long as your
remember it is not a native Linux environment and not everything is
like Linux.

If you want any more advise then come back to me and I can give you a
few pointers.

Tom

On Jul 14, 11:32 pm, Casainho <casai...@gmail.com> wrote:

Bob

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Jul 15, 2010, 3:24:04 PM7/15/10
to rockboxplayer
Hi Thomas

I used Cygwin in the past, but moved to mingw. These both do most of
Linux as you say, but access to raw block devices that dd and fdisk
use do not appear to be supported. I think I will either need a native
Linux or windows app.

I'm going to be porting SD driver code to the target, so maybe I
should have the target code write to the SD card. Or maybe a version
of uboot.
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