MS1? MS2? v2.2? v3.0? MSnS-E? MS/Extra? What does this all mean?
For all intents and purposes, there are two main components in a MegaSquirt ECU: the main board and the processor.
The v2.2, v3.0, and v3.57 boards are the three main boards available. The v3.0 board, as you may have guessed, is newer than the v2.2 board and offers many more standard features. We only recommend the v2.2 board for bare-bones installations; for applications with few technical requirements and a very small budget. The v3.57 board is a surface mount version of the v3.0 board. It’s electrically identical to the v3.0 board but a little more robust, and also more difficult to modify and repair.
MS1, MS2, and MS3 are the three currently available processors. Again, we only recommend the older hardware, MS1, for bare-bones installations. MS2 is the most widely implemented and supported processor. It’s much faster, more user friendly, and more feature rich than MS1. MS2 and MS3 are technically much more closely related than MS1 and MS2. MS3 is the newest processor. It offers even greater speed, USB connectivity, SD card datalogging and expanded input/output (I/O) options.
MS1, MS2, and MS3 processors will work with both v2.2 and v3.0/v3.57 boards, but it’s generally much easier to implement MS2 and MS3 with v3.0/v3.57 boards only.
MS3X is a special expansion board designed for use with the MS3 processor. It offers eight ignition outputs, eight fuel injector outputs, six medium current outputs, four digital inputs, and three analog inputs, all of which are accessible using the MS3 processor.
MS1/Extra and MS2/Extra refer to the firmware used in MS1 and MS2 processors, respectively. Firmware is the software that runs within the processor. The MS1/Extra and MS2/Extra firmware is distinct from the standard “B&G” firmware in that it offers more features and allows MS1 and MS2 based ECU’s to operate many more engine types (e.g. the 420A/Neon engine, etc.).
There is only one codebase for MS3 based ECU’s. The firmware is usually referred to as the “MS3 firmware.”
“MSnS-E” an acronym for “MegaSquirt-n-Spark Extra,” which is an older, now deperecated name, for MS1/Extra. You should avoid the terms “MSnS-E” or “MSnS.”
