MSP430FR5969 interfacing with an Asynchronous external SRAM

[kitepassion]

Dear all,

I would like to use this microcontroller MSP430FR5969 to connect to an external SRAM memory. I need to use an asynchronous SRAM memory with 44 pins, 40 pins are used to drive the memory.
From the datasheet of the micocontroller I see that the GPIOs are 40.
I am not sure that I can use all the 40 pins, anyone here already tried to use all the GPIOs?

Thank you

 

[paulfjujo]

hello,


if you use all GPIO pins to drive the SRAM,
how do you dialogue with external world ?
you need some GPIO pins to have an interface with the Human.. or send result of your application

you can use I2C I/O extender as MCP23017 or SPI model ..or other kind ..
you maybe can use Hardware binary counter as CD4040 (or other..) to drive adresse to SRAM,
driven by software

 

[kitepassion]

Hi Paul,

thank you for the quick reply. Actually the main purpose is to read and write from the memory and only some times connect to the external world. I was thinking about a small multiplexer but still i need to use another pin to drive it.. and I actually do not have anymore pin available. So your solution seems very appropriate.

 

[josiphal]

Actually the main purpose is to read and write from the memory and only some times connect to the external world. I was thinking about a small multiplexer but still i need to use another pin to drive it.. and I actually do not have anymore pin available. So your solution seems very appropriate.

And why you need external RAM at all? Internal FRAM/SRAM is not enough or what?

 

[kitepassion]

And why you need external RAM at all? Internal FRAM/SRAM is not enough or what?

The application rely on the SRAM...

 

[josiphal]

The application rely on the SRAM...

How and why? And internal 64 KB FRAM that can be used as RAM is not enough?

MSP430 devices are not designed to be used with external memory chip's and don't have data/address buss on external pins. However they have SPI/I2C interface that can be used for this (also with SD card). I working with MSP430 and never have need to use it with external memory, because complete internal flash can be used for data storage on-the-fly during program execution. With FRAM is even easier, because it behave (write/read) like SRAM, without taking care of flashing timing.

 

[kitepassion]

The application will be SRAM testing... that's why I need it.. and It is mandatory an FRAM microcontroller

 

[josiphal]

The application will be SRAM testing... that's why I need it.. and It is mandatory an FRAM microcontroller

Well, if target is just spending your free time, with learning new things, there is no any problem with this. But if this is related to some commercial / processional project, than you selected wrong micro.