342-0220/21-A/B clearly printed on the ROM with a respective 1983/1984 copyright date.
The new ROM addresses a revised stepper motor in the 400K Sony drives. Newer drives are incompatible with the older ROMs, a fact with which one must be aware when swapping out 400K drives with 64K ROMs.
Addressed in this topic:
viewtopic.php?f=7&t=11687
And I agree with Dennis re: camera lighting. All Mac 128K & 512K/es have front badges with beige backgrounds which exactly match the color of the case. All rear case badge's background color are the darker olive accent color. There are no exceptions to this, and was consistent all the way through the last 512Ke manufactured even after the case switched to Platinum. So it is either lighting, or someone has switched them around, or they have discolored with age, or appear gray compared to the discolored case.
And no, there is not one good reference book which will have all of your answers. Most of this knowledge comes from direct experience, and tidbits gleaned from Apple's TIL, and numerous books, and photos from period literature, BBS and usenet archives.
The new ROM addresses a revised stepper motor in the 400K Sony drives. Newer drives are incompatible with the older ROMs, a fact with which one must be aware when swapping out 400K drives with 64K ROMs.
Addressed in this topic:
viewtopic.php?f=7&t=11687
And I agree with Dennis re: camera lighting. All Mac 128K & 512K/es have front badges with beige backgrounds which exactly match the color of the case. All rear case badge's background color are the darker olive accent color. There are no exceptions to this, and was consistent all the way through the last 512Ke manufactured even after the case switched to Platinum. So it is either lighting, or someone has switched them around, or they have discolored with age, or appear gray compared to the discolored case.
And no, there is not one good reference book which will have all of your answers. Most of this knowledge comes from direct experience, and tidbits gleaned from Apple's TIL, and numerous books, and photos from period literature, BBS and usenet archives.