Welcome aboard Simon original Daydream developer, thank you

Started by Rob Blessin Black Hole, July 24, 2015, 03:17:20 PM

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Rob Blessin Black Hole

Hello Simon: I approved you so hopefully you will see this post I went ahead and posted your correspondence here as well as it will be a great help having you on this project as the original developer your help is invaluable and much appreciated! Best Regards Rob Blessin I'll also add this to the existing thread!


Hi Rob,

I came across your project to reverse engineer daydream. Back in the 90's, Andy Grawehr did the hardware, marketing, sales, legal, run the company, etc. I was the guy who wrote the entire software (NeXT Step launcher, DSP, MacOS device drivers, etc). It was basically just a two-men company those days. I left Quix a very long time ago and do not have any records (for legal reasons). But I will try remember as much as possible.

For a start: the 8-pin chip is an (512 byte?) EEPROM. It holds the MacOS NVRAM/PRAM as well as a decryption key for the daydream kernel. I think we also kept some statistical information around in that chip as well as the name of the customer that bought it. Reading the content back should be fairly simple.

While the GAL isn't that complicated (basically generating the chip selects), reverse engineering the protocol we talk over the DSP port is a different story. There is quite some bit fiddling going on and I would have to spend  some time with a scope to get that back.

As far as I remember, I first read the entire EEPROM, run some sanity checks on the content and then start reading the Apple ROMs. On shutdown, the EEPROM is written back from am memory copy that is kept around in the daydream kernel. So this might be a good starting point because much less data is involved on shutdown compared to the startup. There is also a background task in the kernel while running MacOS that reads from time to time from the DSP port to check if the daydream box is still plugged in. That's also worth a try since only a few bytes are transferred each time.

A different approach would be hacking the software. We were really proud of our copy protection back then (as far as I know, daydream never got hacked) so that's a challenge of it's own. But we had a version that was able to read the Apple ROM images from disk an that code might still be around in the daydream kernel.

BTW, if you plug in the daydream box without Apple ROMs, you should be able to play Tetris (built into the daydream kernel) instead of booting MacOS :-)

I registered on the forum and await the ok from your admin.

Bests,

Simon 8)  8)  8)
Rob Blessin President computerpowwow ebay  [email protected] http://www.blackholeinc.com
303-741-9998 Serving the NeXT Community  since 2/9/93

mikeboss

a very warm welcome simon! BTW: one of the cubes used at quix ended up being in my NeXT collection ;-)

regards,
michael
October 12, 1988 Computing Advances To The NeXT Level