Surfing the web pseudo-randomly I found this nice toy: an ENC28J60 based breakout board.



(available here and also here, in the Other - Ethernet section)

Then, remembering the VERY basic knowledge about electronic design I acquired in the university, I came up with the following:



It is a very very simple Ethernet card design for MSX, using the above device. It would be accessed the crude way, by directly interfacing the SPI port via MSX port 0 (this configuration is the one requiring less logic components). The flip-flop is needed because CS must be low during the whole SPI transactions, and the short-circuited AND gates are to compensate the 3.3V level outputs (MSX requires 5V).

So, while Dumas goes its way, this could be an alternative for playing a little, for people skilled enough to make its own hardware... which is not my case.

What do you think? Would this design actually work, or am I missing something? (apart from converting this design to real components, of course)

I respond to myself. 3-state buffers are needed so that the ENC28J60 does not mess with the data bus unless port 0 is explicitly accessed:

a very cheap ethernet, perhaps can be added to some ROM games.

Yes CHEAP

Well, you need a couple of extra components as well. The ENC28J60-H breakout board costs around 25€; add a 13 input NAND gate, a voltage regulator, a flip-flop and a 3-state buffer. Anyway, indeed, it would be not at all expensive.

Perhaps is easiest use some other board with 8bit interface. More similar to obsonet.