Adding RAM to STR750 or STR710

billw1 · ‎2007-03-09

Posted on March 09, 2007 at 12:19

billw1 · ‎2007-03-05

Posted on March 05, 2007 at 21:18

I am trying to decide if an STR710 or STR750 would be a better chioce for a new project. In both cases, the internal RAM is insufficient and external RAM would have to be added. The mechanism seems to be different for the different models, EMI vs SMI, and I am looking for information on which would be the better model given the requirement to add RAM. Also, is SMI even a choice for external RAM? If not, what would be the mechanism on the the 750?

Thanks.

kaouther · ‎2007-03-05

Posted on March 06, 2007 at 05:39

Dear BillW,

Exactly, the STR710 and STR750 have different models of external memory interface.

Indeed, the serial memory interface â€œSMIâ€� on STR750 could only interface an external SPI memory device which will be used as data or program memory and can not interface an external RAM. However, for STR710 the External memory interface can be used to interface Rom, Flash or SRAM memories. So, if your application requires adding an external RAM, you need to use the EMI on STR710.

I would suggest you to have a look on STR75x and STR71x reference manual for a complete detailed description about the SMI and EMI features and functionality as well as the product features that could helps you to make a better choice for your whole application and for any further data let us know.

Thanks.

sjo · ‎2007-03-09

Posted on March 09, 2007 at 12:19

The str710 or even str9 would be the better choice.

If you really want to use the 750 then one possible solution is to use spi FRAM from Ramtron - depending on how much more memory is required.

Regards

sjo