By Philippe Dubois, Chairman.

For this second article, we're going to take a first general look at the machine to check its overall condition and also to start taking a look at the many electronic cards that make it up and see what their roles are.

Micral N acquired and restored by the MO5 association

The Micral N has arrived at the MO5 association and our top experts are now hard at work examining it. First of all, we're going to look at it from every angle, checking for corrosion and broken parts. Then we'll start analysing the electronic cards inside.

Close-up of the Micral N façade and logo from the MO5 association

In keeping with what we observed when we bought it in the previous article, the machine is visibly in good cosmetic condition. The front panel seems particularly well preserved: there are no broken or missing switches, and markings such as the R2E logo, the name of the machine and the instructions above each control switch are all present and show no scratches.

Behind the Micral N are all the electronic cards that ensure its operation

Turning the machine over, we can see the large set of electronic cards it contains. When we bought it, neither we nor the seller had any idea of the role of each of the cards. This is important because the order in which they are plugged in may have a role to play in the operation of the computer.

Close-up of some of the electronic boards on the Micral N from the MO5 association

One of the special features of this historic microcomputer is that it uses what is known in IT jargon as a 'backplane', i.e. a data bus with hooks that allow up to 22 electronic cards to be added, all communicating with each other.

This is how the Micral N works: there are several input/output cards for communicating with the outside world, as well as several memory cards (including RAM and ROM with a fixed program) and finally a CPU card that talks to all these things so that the computer can function.

In the background, the PLURIBUS data bus, patented by R2E.

In our example, there are several RAM cards, one or two ROM cards, a CPU card and several as yet unidentified I/O cards.

Now we can take a closer look at each card it contains. But that's a story for a future article, so see you soon!

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