topic Re: One for the designers? MCF5274L and SDRAM in ColdFire/68K Microcontrollers and Processors

One for the designers? MCF5274L and SDRAM

Southernboy — Mon, 12 Mar 2007 02:54:43 GMT

Is it possible to use an MCF5274 with an SDRAM such as the MT48LC16M16A2 which I have also used on the MCF5407, or can the processor just handle DDR memories?

Many thanks in advance

Southernboy

Re: One for the designers? MCF5274L and SDRAM

TomFreescale — Mon, 12 Mar 2007 23:47:02 GMT

Hello Southernboy,

If you are asking for free help from a Freescale designer, you should at least show enough respect to sign your own request.

Re: One for the designers? MCF5274L and SDRAM

Southernboy — Tue, 13 Mar 2007 01:54:04 GMT

To TomFreescale: It was a straight question. Why the trash response? Perhaps someone with very little to occupy their time maybe.

Re: One for the designers? MCF5274L and SDRAM

SimonMarsden_de — Tue, 13 Mar 2007 17:17:56 GMT

Hi

I'm not a Freescale person, but...

Looking at the documentation, I'm fairly sure that SDRAM controller on the MCF5274L can only handle DDR.

For other processors like the MCF5475 which can handle both SDR and DDR, Freescale have documented both fairly clearly, and there is a bit in the SDCR register to select which type of SDRAM you have. The MCF5274L doesn't seem to have this.

Hope this helps

Simon

Re: One for the designers? MCF5274L and SDRAM

JWW — Tue, 13 Mar 2007 22:40:07 GMT

Southernboy,

To allow for a reduced pinout, the 5274 and 5275 families leverage DDR technology to get 32 bits of data on only 16 data pins on the package.

On some of our larger, less pin constrained parts, we offer SDR and DDR. The 548x and 547x offer both.

But to be honest.. I've been using DDR for about 6 years now, and it works quite well with the Coldfire family and I wouldn't go back.

Integrating a DDR solution on the 5274 is relatively straightforward.

I would be happy to help if you need some guidance.

Others on the forum may have similar questions, so if you are thinking of using DDR but have concerns...Then just fire some questions to the forum and we'll try to help.

Best Regards,

-JWW