Difference between a Megasquirt 2 vs Megasquirt 1 3.0 with MS2 daughter board
 

Tried searching with no luck to an answer:

I just purchased what I thought to be a MS2 from a previous member on here. When it arrived, it appeared to be a Megasquirt 1 pcb 3.0 with a MS2 expansion board. The previous owner said it was originally built by brain and I'm trying to figure out if it's missing any additional features that the newer MS2 ecus have.

After some searching on diyautotune.com it appears that the kit that may have been used is this one:
MegaSquirt-II Programmable EFI System PCB3.0 - Kit w/ BLACK CASE DIYAutoTune.com

The previous owner was using this on a 94-95 miata and I was about to change up the connector pin outs so that it'd work fine for my 96-97. Looks like this version is much more of a bi*** to switch up.

https://www.miataturbo.net/attachmen...ine=1369465779
https://www.miataturbo.net/attachmen...ine=1369465779
https://www.miataturbo.net/attachmen...ine=1369465779
https://www.miataturbo.net/attachmen...ine=1369465779

That is an MS2.

It has the V3.0 mainboard and the MS2 processor (daughterboard). So its an MS2 all right.

MS1, MS2 and MS3 are all built on the V3.0 pcb. They only differ by the processor used. As Jim already said, you have a MS2 processor. You could plug in a MS3 processor just as well if you wanted.

To restate what's already been said above, there is no such thing as an MS1 motherboard or an MS2 motherboard. The only difference between an MS1 and an MS2 (and an MS3, for that matter) is which processor is installed into the socket at position U1, and how some of the ancillary wiring is configured.

There have been four major revisions of the motherboard, and in an extremely broad sense, they are all more-or-less intercompatible.

The original v1.01 boards have been gone for more than a decade.

The v2.2 board was introduced in 2002, and is still available, although it is NOT recommended for new builds.

The v3.0 board came along in 2005, and sort of became a de-facto standard, in that it continues to be the primary basis of most builds.

The v3.57 board is schematically almost identical to the 3.0, they just re-jiggered it to use surface-mount parts so that it could be factory-assembled more easily.


So, that 3.0 board you have could be used for an MS1, and MS2, or even an MS3 build. There is no strict correlation between the revision of the board and the "model" of the ECU- that is determined by the CPU.


* note that I am ignoring DIYAutoTune's proprietary products such as the MSPnP2, the MS3Pro and DIYPnP, which do in fact use dedicated motherboards. The above generalizations apply to the traditional "built it yourself" variety of Megasquirt ECUs. It does, however, include the original MSPnP and MSPnP2 family of products, which use the standard 3.57 motherboard internally.

It looks like a frog shit on your wiring harness.

Weird location for that extra DB9

The MSPNP Gen2 is actually built on an in-house designed mainboard.

The original MSPNP Gen1 was based off a MS1 V3.57

Gotcha. I've actually never seen the inside of a PnP2- assumed it was following the same paradigm. I take it you've switched to the MicroSquirt Module for that one?

Corrected original post.

(For those who don't know, the MicroSquirt Module is essentially a complete implementation of the MS2 ECU, minus the output drivers, on a tiny little daughterboard. It was basically B&G's concession to the usual MS licensing agreement intended specifically for use in "proprietary" products like the DIYPnP, or in total custom, one-off builds like the HellaSquirt I did a couple of years ago.)

Yes, a Microsquirt Module is employed as the processor, which takes care of the hardware and firmware licensing. We break it out through our proprietary mainboard.

MS3-Pro EMS and MS3-Pro Module are also our designs, neither using original B&G hardware, however both are fully licensed.