0
\$\begingroup\$

Please. I need somebody can tell me if I can replace a SD card module of arduino to use instead a MB85RC256V fram module 32KB. I want to save power of 3.7 battery, but I am not sure if I can use a fram to store sensor data. the datasheet of MB85RC256V says :

it is suitable for the log management and the storage of the resume data, etc.

My idea is to read pressure/temperature each 15min and maybe send the data to server twice in a day. After send the data I want to clear the fram memory to can store more sensor data.

The format of each line to store could be:

yyyy-mm-dd,hh-mm-ss,pressure-value,temperature-value,some-id

I think 1000 lines of this is 32KB. If I measure each 5min I got in one day 288 lines (maybe 10KB)..?

Is it possible to do?

\$\endgroup\$
0
\$\begingroup\$

From what I’ve read of FRAM, writing is more like RAM so you do not have to erase pages before writing, as in flash memories. This is confirmed in looking at the I2C command set and finding no erase commands.

Basically, with one command, you can write sequential bytes to any location in the FRAM. Read/write cycle limits (reads require rewriting so reads must be considered too) are much higher than erase/write cycle limits in flash but are still finite. You could probably get away with always restarting from the beginning but I’d still suggest using the device as a circular buffer so it wears evenly.

Note that this is an I2C device where an SD card is SPI (in the simplest mode). Therefore, it’s not a direct replacement. The interfacing and code is different but still quite doable on an Arduino.

\$\endgroup\$
  • \$\begingroup\$ Thanks you for your reply... but Can I store data like log line for sensor like a SD card ?? \$\endgroup\$ – asterix May 23 '19 at 11:30
  • \$\begingroup\$ @asterix I’m not actually familiar with the SD card library for the Arduino but you’re probably going to need to treat the FRAM as a raw block of memory and manage everything yourself. Basically keep track of how far you’ve written and append the next line right after. \$\endgroup\$ – DoxyLover May 23 '19 at 18:19
  • \$\begingroup\$ Thanks, I bought a FRAM module for arduino, I need to learn and test. \$\endgroup\$ – asterix May 23 '19 at 23:54

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.