Kai Robinson

@cheesestraws Oooh, i may have to take you up on that - i basically need a whole other SE board, so i have some duplicate customs for testing...

Knocked up an adaptor for the SE ROM's - i have a funny feeling mine aren't making proper contact in the sockets, the legs, even cleaned, are tarnished...the ones from the spare board i have...well i tried removing them and the legs stayed in the sockets, so i now have a load of icosaoctaplegic Mask ROM's I have 10 prototype boards in a panel with ENIG and V-Scored edges on the way from PCBWay (Making use of the $100 or so commission i earned from the Amiga stuff i've done in the past) so if anyone wants to test these, i have 9 available.

An Oscilloscope is on the way - i do have a logic analyser - but i'll be damned if i can find a DIP64 IC test clip!

Well, most ttl has a bit of leeway, I'm hoping it hasn't taken out the BBU - everything else is expendable... Here's the result of a 20 second power on with a set of 256k simms :

I'm thinking my analogue board is potentially in need of repair as well - seeing as the video is very off centre as well as being wonky...voltages are something i'll have to measure....if only i had an extension cable to be able to test this flat on a bench! Anyone make one at all?

I just checked the test points for voltages - instead of reading +5v, it's reading +7.5v!!! I think my analog board has potentially killed some chips...

Okay, it's done... See pics for details! No boot, but a checkerboard again at least...

Only $254...

I know! I'm unreasonably excited for this now

Porchy has worked some magic and behold - a .JED for the GLU!! A Proper fuse map! :o Is anyone in a position to test this aside from me? apple1.jed

@Trash80toHP_Mini - here you go: https://drive.google.com/file/d/1qXWsemDG4Ypb7kUFZebFNU_NZiY-CQuv/view?usp=sharing

http://www.merlintec.com/download/unitron1.pdf http://www.merlintec.com/download/unitron2.pdf For the full size pdf's of those equations.

In addition, i've handed the GLU and ADB chips to porchy from jammaarcade as he has a lot of experience reverse engineering - he's been right on it from the get-go, and reported that the initial equations are indeed correct, but looks like pin 18 is tristate and there's some /OE stuff to sort out still...

Posting these - these are the unitron PAL reverse engineers of the original 512k Mac - which should still be applicable. Also, found this passage of text - @quorten this'll be of interest to you: About six months after the Macintosh was introduced, Apple announced two improvements: the external floppy disk and the 512K model (known as the "Fat Mac"). Though this new machine replaced 4164 chips with the 41256, its timing was not changed to take advantage of this. A year later the Mac Plus brought the use of SIMMs for memory expansion and a SCSI interface for external peripherals, bu

@quorten there's this, too: http://archive.retro.co.za/mirrors/homepage.ntlworld.com/kryten_droid/AppleMac/apple_mac_logic.htm