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 of 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 slots 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) slot, 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. If you're using this in the main 32K RAM socket, nothing needs be done but ensure you install the FRAM in the correct orientation, pin 1 being bottom right.

Kit Options

As with my other kits, you can buy just the PCB, or you can buy the parts partially assembled, with the SMD parts now fixed at the factory (needing you to only solder the DIP pins) or fully assembled. Only the fully assembled versions will be fully tested in my actual TEC-1G and some data written to it and read back to ensure full operation.

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.

DIP Socket

The base TEC-1G kit does not come with a second, spare 28 pin DIP socket for additional memory. If you don't happen to have one lying around, I have that as an option to include.