DIY Dreamcast BBA Clone

[TJ_Kat]

Don't know if anyone has posted this page before.

http://f17.aaa.livedoor.jp/~takotako/g2bus.php

The page has a USB adapter, a few different LAN adapters, and at the bottom of the page it has a 'BBA clone experiment'. I don't know if any of these things actually work since I can't read most of the page, but there are a lot or people more knowledgeable than me around here who might want to check it out.

[kendrick]

I've seen this before. The idea is that you take a later model Realtek Ethernet controller and hope that it's a superset of the instruction set found in the model C chip you get with the Dreamcast BBA. You take advantage of some native PCI bus architecture and you reverse it so that it's talking to a bridged network connection (rather than trying to connect it to 100-BaseT directly.) That extra chip on the right looks like a writable ROM to store unique data like the PPPOE and MAC address data. It's ambitious, and probably cost about $300 in parts or so.

[TJ_Kat]

Not to be difficult, but I'm curious how you came to that price point? With the exception of that big altera chip and that other chip shown in pic 6, most of that stuff looks like it could be had dirt cheap. I actually probably have most of those things lying around and didn't pay more than $5 or $10 for the lot of it.

Don't get me wrong, I'm only trying to satisfy curiosity here - I'm not planning to build one of these (I already have a BBA and treat it like a holy relic) - but I didn't think 2 chips would cost that much.

[kendrick]

The ROM is the expensive part. My experience with ordering those ICs is that you'll get horrible pricing on single units. If you're willing to buy multiples (or if you have one lying around) then obviously the price goes down. My guess is that the Dreamcast has to be able to address the thing, which is why you couldn't just substitute any old writable EEPROM chip. It's entirely possible I'm wrong about that point.