How to drive a FRAM--FM22L16 using FSMC in the STM32F205ZET6

[Mo Zhengpei]

Posted on March 24, 2017 at 03:57

My MCU is STM32F205ZET6, and i want to use it to drive a external FRAM-FM22L16 by using the FSMC, but i have no idea to how to config the FSMC, also, I get confused about computing the ADDSET: address setup time,DATAST: data setup time,ACCMOD: access modethe of the FM22L16 .

did anyone have used it before? i would be great appreciated if someone could answer my questions.  Thanks.

[waclawek.jan]

Posted on March 24, 2017 at 09:08

According to datasheet, this memory is a drop-in replacement for SRAMs (except the /ZZ pin which you can tie simply high if you don't want to use the low power function of the memory), so you can use whatever example ST has for SRAMs at FSMC.

For SRAMS, you can generally use FSMC mode 1. Follow the timing diagrams and tables for individual modes in the RM: ACCMOD is don't care in that case: DATAST determines determines how long the /RD and /WR pulses last, for read, match that with tOE (check with STM32 DS how long before trailing edge of /RD does it sample input data), for write, match with tWP; use the longer of two values. ADDSET is a time added before the DATAST time, so match that sum with tCA/tCE/tCW. If you don't need any extremely high performance, add some safety margins.

JW

[Mo Zhengpei]

Posted on March 26, 2017 at 03:46

Thanks for answering, these days  i am trying to figure it out, Thanks very much

[mbedx]

Hi Mo, Were you able to interface? Could you please share additional details?