Writing to External Ram on 56720 dev board

Started by Pete Johnston March 17, 2010
Hi Guys

Sorry for emailing you direct but the forum won't let me in at the moment.

I'm trying to write to the external SDRAM SRAM and FLASH as per the as
per the extract from the DSP56720BUG.pdf below.

I think need to set up the EMC to match the Chips used and a Memory Map
of where they live.

Do you know of any example code in Assy that makes use of this external
memory?

BTW Christian, with your help I successfully made my dev board self boot
off the I2C EEPROM but found that it is only 256Kbits and not 256Mbytes
as it states below. It's only 8000 times smaller than I was expecting.

So I now see why you said that it was not suitable for a big pool of
sound clips as I had planed on using.

Thanks for all your help

Pete Johnston

3.1 DSP56720/DSP56724 Daughterboard Overview
The DSP56720/DSP56724 daughterboard connects to the DSPAUDIOEVM
evaluation motherboard
(EVM) using two 96-pin connectors. The daughterboard includes several
types of external memories:
8M (2 2M 16-bit 4 bank devices) of SDRAM
512K (3 512K 8-bit devices) of SRAM
128K (3 128K 8-bit devices) of FLASH
256Mbyte I2C EEPROM
256Mbyte SPI EEPROM
Hi Pete,

Attached code FYI.

2010/3/17 Pete Johnston

> Hi Guys
>
> Sorry for emailing you direct but the forum won't let me in at the moment.
>
> I'm trying to write to the external SDRAM SRAM and FLASH as per the as per
> the extract from the DSP56720BUG.pdf below.
>
> I think need to set up the EMC to match the Chips used and a Memory Map of
> where they live.
>
> Do you know of any example code in Assy that makes use of this external
> memory?
>
> BTW Christian, with your help I successfully made my dev board self boot
> off the I2C EEPROM but found that it is only 256Kbits and not 256Mbytes as
> it states below. It's only 8000 times smaller than I was expecting.
>
> So I now see why you said that it was not suitable for a big pool of sound
> clips as I had planed on using.
>
> Thanks for all your help
>
> Pete Johnston
>
> 3.1 DSP56720/DSP56724 Daughterboard Overview
> The DSP56720/DSP56724 daughterboard connects to the DSPAUDIOEVM evaluation
> motherboard
> (EVM) using two 96-pin connectors. The daughterboard includes several types
> of external memories:
> 8M (2 2M 16-bit 4 bank devices) of SDRAM
> 512K (3 512K 8-bit devices) of SRAM
> 128K (3 128K 8-bit devices) of FLASH
> 256Mbyte I2C EEPROM
> 256Mbyte SPI EEPROM
>
--
Best Regards.

Johnny Chen
Hi Jonnny

The SDRAM worked brilliantly with very little tweaking

Thanks so much.

But I've had no joy with the Flash code.

Does it also need some extra initializing?

Is it made for the 56720 running at 200mhz?

I noticed that BR0_DATA_LOW has bits [12:11] both set for 24 bits but my
ref manual says these bits are reserved.

Is maybe my 56720 ref manual out of date.

It doesn't muck up the rest of the software operation at all it just
simply returns nothing when written to and read from.

Any other ideas or is there an example of reading and writing tests as
with the SDRAM example?

Thanks ever so much

Pete Johnston
Johnny Chen wrote:

>
> [Attachment(s) <#TopText> from Johnny Chen included below]
> Hi Pete,
>
> Attached code FYI.
>
> 2010/3/17 Pete Johnston > > Hi Guys
>
> Sorry for emailing you direct but the forum won't let me in at the
> moment.
>
> I'm trying to write to the external SDRAM SRAM and FLASH as per
> the as per the extract from the DSP56720BUG.pdf below.
>
> I think need to set up the EMC to match the Chips used and a
> Memory Map of where they live.
>
> Do you know of any example code in Assy that makes use of this
> external memory?
>
> BTW Christian, with your help I successfully made my dev board
> self boot off the I2C EEPROM but found that it is only 256Kbits
> and not 256Mbytes as it states below. It's only 8000 times smaller
> than I was expecting.
>
> So I now see why you said that it was not suitable for a big pool
> of sound clips as I had planed on using.
>
> Thanks for all your help
>
> Pete Johnston
>
> 3.1 DSP56720/DSP56724 Daughterboard Overview
> The DSP56720/DSP56724 daughterboard connects to the DSPAUDIOEVM
> evaluation motherboard
> (EVM) using two 96-pin connectors. The daughterboard includes
> several types of external memories:
> 8M (2 2M 16-bit 4 bank devices) of SDRAM
> 512K (3 512K 8-bit devices) of SRAM
> 128K (3 128K 8-bit devices) of FLASH
> 256Mbyte I2C EEPROM
> 256Mbyte SPI EEPROM
>
> --
> Best Regards.
>
> Johnny Chen