• TEC-1G 32K FRAM (Non-Volatile)

    05/06/2024 at 07:37 • 0 comments

    ## What is FRAM?

    FRAM acts pretty much exactly the same as standard 62256 SRAM we all use in our TEC-1G, except inside it has tiny ferrite donuts that get charge with a magnetic polarity depending on whether you're writing a 1 or a 0 to that cell. When the power goes off, the magnetic polarity hangs around, similar to how a VHS tape holds onto the information on it. When you power back up, all your program is exactly where it was when you turned your machine off.

    The RAMTRON 32K FRAM chip used to be available in 28pin DIP configuration (I actually own two if them!) but were discontinued a long time ago and are now rarer than Dodo Birds. But the SOIC (surface mount) version of them is still readily available. So all that needed doing is making a carrier which is what we have here.

    ## How to Use the 32k FRAM - A simple Plug & Play

    The TEC-1G has **two** 28 pin sockets that can take this FRAM module. In the left slot, the FRAM becomes your main system memory, starting from $0000 and goes up to $7FFF, making up 32K that never loses its contents! In the right (Expand) socket, you have access to 32K by way of two 16K windows. Controlling which window the TEC-1G "sees" is done with the Fn-E shortcut when in the Monitor, or using the "Toggle Expand" in the main menu. I use this to backup any programs I have in main memory and then flick the EXPAND off, to "hide" that portion of FRAM from the machine, so it cannot get corrupted by any rogue program.

    For the EXPAND socket, just make sure you have the "chip size" jumpers set correctly to be able to work with 28pin chips, and set to "other" on the switches.

    Please note that this FRAM can be used with some RC2014 / RCBus systems, some Microbee machines, and any retro computer that can use a standard 62256 SRAM, as it is pin- and timing-compatible.