Help with selection of external memory.

[Thiago Cavalcanti]

Posted on March 29, 2018 at 11:25

I am using DCMI peripheral to drive camera modules. At this point, I am able to obtain images with 320x240, 16 bits/pixel. I am working with a display connected via FSMC to the MCU and the display already provides enough memory space. But now I want to increase the image resolution to 1600x1200, 16 bits/pixel. For that, I think I'll need about 4 MiB available. Could anyone give me suggestions of memory module [type (SRAM, DRAM), brand, etc) that I could use? 

#external-memory #memory-space

[waclawek.jan]

Posted on March 29, 2018 at 11:59

Before deciding on this detail, think first about the possible consequences of increasing the resolution - thus required processing and shear data movement requirements - 25-fold.

You may perhaps want to do more substantial architectural changes and move to more powerful platforms.

JW

[Thiago Cavalcanti]

Posted on March 29, 2018 at 14:14

I am currently using an STM32F407VG. Isn't it enough to handle it?

[AvaTar]

Posted on March 29, 2018 at 14:31

That's yours to decide.

As

Waclawek.Jan

meant: 1600*1200 / 320*240 =

I hope you realized the implications.

[Thiago Cavalcanti]

Posted on March 29, 2018 at 14:37

I understand. Thank's for the advice. But still I would like to give a try to see what would be the final result. If it is not desirable, I might consider an upgrade.

[AvaTar]

Posted on March 29, 2018 at 15:18

I had a project connecting a TFT to a F407 via 8-bit bus interface (i8080 type), not FSMC.

The driver was optimized as far as possible, achieving an image clear (accessing all 320x240 pixels) in about 1.5 seconds.

The external memory interface might be faster - measure your timing.

Multiply it by 25 to get an idea of the expected times.

Consider how you manage to transfer 4 Megabytes through the SRAM.

[Thiago Cavalcanti]

Posted on April 02, 2018 at 09:08

Searching among the drivers on the STM32CubeMX I found that there is an example for the IS61WV102416BLL-10MLI SRAM module, which is 2 Mega bits. I'll try to use one of these and start with a lower increase, say 640x480 pixels, to see what will be the results.