Threaded Mode | Linear Mode

Dan · (This post was last modified: 07-24-2019 11:08 AM by Dan.)

This paper describes FRAM, a type of non-volatile memory that has low current consumption, fast write and high write endurance (an example is given where a data logger using Flash memory would have a lifetime of only 3 hours compared to 3 million years using FRAM memory).

TI offers microcontrollers with 16kB FRAM, which is too small, but Cypress have memories between 4kB and 4MB. If I am able to interface the microcontroller I am using to them I would be able to retain the contents of RAM when power is removed.

**rprosperi** · 07-24-2019, 12:39 PM

FRAM has been used in several projects in this community for some time. One eBay seller offers 48 Series 'RAM' Cards which use FRAM, and member Hans Brueggemann designed and offered an extraordinary HP-71B memory module which contained up to 1MB of FRAM. There are several threads about FRAM71B, here's one:

https://www.hpmuseum.org/forum/thread-62...ht=FRAM71B

burkhard · 07-24-2019, 03:30 PM

(07-24-2019 12:39 PM)rprosperi Wrote: FRAM has been used in several projects in this community for some time. One eBay seller offers 48 Series 'RAM' Cards which use FRAM, and member Hans Brueggemann designed and offered an extraordinary HP-71B memory module which contained up to 1MB of FRAM. There are several threads about FRAM71B, here's one:

https://www.hpmuseum.org/forum/thread-62...ht=FRAM71B

Sigh... I sure would like to pick up one of those FRAM71B modules.

Dan · (This post was last modified: 07-25-2019 03:10 AM by Dan.)

Cypress offer this kit, which can be used with an Arduino, and Adafruit this breakout board

Dave Frederickson · 07-25-2019, 05:26 PM

(07-24-2019 03:30 PM)burkhard Wrote: Sigh... I sure would like to pick up one of those FRAM71B modules.

Folks do get disenchanted with their modules. I've seen a couple of them sold in the Classifieds. Give it a go. You've nothing to lose.

Sylvain Cote · 07-25-2019, 06:06 PM

(07-25-2019 05:26 PM)Dave Frederickson Wrote: Folks do get disenchanted with their modules. I've seen a couple of them sold in the Classifieds.

That always amaze me, this is really the holy grail for the HP-71B.
I have multiple FRAM71 modules (3x FRAM71-1024, 2x FRAM71B-1024) and will never considering selling them ... except maybe, when I decide to sell-out my collection.