VME Legacy Board Compatibility

You might be able to use more than you think

At least a few times a month we will get a request from a customer for a very specific product model. They often explain to us that they have been searching high and low with no success. After our standard review of their application we determine that the product that they are looking for is correct, however they could easily substitute several others from the same product family.

“Many legacy VME boards are Form, Fit, and Function (FFF) compatible across multiple detailed part numbers”

Usually the differences in the part number delineate added functions that you may not need; for example SCSI, Ethernet, or the amount of RAM on the board. Let’s look at the Motorola MVME162 series. The older MVME162-023 board has 4MB, SCSI and Ethernet. It is FFF for all the sub-models: MVME162-020, -021 and -022.

MVME162-023 showing both Ethernet and SCSI chips on board

MVME162-022 showing only the Ethernet chip and no SCSI chip

MVME162-021 showing only the SCSI chip and no Ethernet chip

If you are looking for the MVME162-020 board (4MB, NO Ethernet, NO SCSI) you could use the MVME162-021. The fact that SCSI also is supported on the MVME162-021 does not affect FFF. The same is true for the MVME162-022 and MVME162-023. Additionally, the MVME162-04X boards may also work for the application. These models have same features but have 8MB of memory instead of 4MB. There may be rare circumstances (probably <5%) where there may be minor issues usually related to differing memory size.


Call us to discuss compatible FFF solutions, you might be a lot closer to finding a replacement than you originally thought!