Mac128 wrote:Personally, I'm not particularly interested in booting a 128K or 512K from a hard drive. I'm more interested in the expanded storage options it affords, to cut down on disk swaps. I feel like if you're gonna run an original 1984/85 Mac, booting off a floppy is mandatory. I actually kind of like the hand off startup floppy that automatically switches over to the hard drive and then ejects itself. Very elegant, and for me part of the experience. A flash drive that tapped into the ROM would be amazing!
Isn't *all* the floppy swapping "part of the experience"? If you're looking for an authentic pure-to-Apple's-"vision" early Mac experience that involves a hard drive the only legitimate answers are to use an HD-20 or upgrade to a Plus. ;^b
(It seems to me a schizophrenic set of desires to want to keep the 64k ROMs for "authenticity" yet still want some sort of authenticity-destroying internal hardware add-on to get non-Apple-sanctioned functionality on the system. Isn't that a bit like a car collector *insisting* that their 1908 Model T retain the planetary gearset transmission, wet clutch, starter crank, and all original suspension and brake parts while at the same time scheming on ways to transplant a Chevy V8 engine into it? Besides the obvious technical issues, well... if you want the "authentic" Model T experience you're stuck using it stock, or possibly with period upgrades that preserve the essential factory layout of the car *only*. Anything else puts you in the same category as people who make "T-Bucket" Rat Rods, and at least the people who make those usually have the good sense to upgrade the auxiliary components to units rated to handle the power they've added to the car.)
That snipe aside it seems to me there's zero-hardware solutions to this if someone gets off their rear and fires up the C compiler. John Bass' "vaunted" SCSI code was a hack on example code for a RAMdisk included with his C compiler. He said so in his article. The original Mac has two serial ports, so why not just likewise hack a RAMdisk driver to use one of them to speak to "server" software that dishes up disk images from a modern machine? (A UNIX box, or a Macbook with a USB serial adapter. Was it Porter who said in some earlier post that he'd written just such a driver to use the floppy drive on his DOS machine for Macintosh storage years and years ago?) Using disk images over serial would be "slow", but everything's slow on a Mac 128k, and such a thing could be considered "historically correct". (Serial hard drives like the Tecmar MacDrive did exist for the early Macs.)
If it's acceptable to use an HD-20-esque method of storing the driver on a pre-boot floppy then the hardware hardly matters. Write the driver first for a serial port connected to another computer (the server software would be trivial, and this time I say that meaning that even *I* could probably write the UNIX code for that). Once you have the bugs worked out of that you could instead target a dedicated hardware hack. A microcontroller sitting on a passthrough board snooping the address lines in a ROM slot, ala John Bass, Dove SCSI boards, etc, is an obvious thought. Practically every microcontroller on the market has example code for reading and writing SD cards over SPI in their code library. (Even a powerful one like the Parallax Propeller, which would allow you to write practically the entire program in a semi-high-level language, costs under $10 each. If you went into "mass production" with a printed circuit board you might be able to get a kit price down to under $50 for a printed circuit board and all the parts.)
People really get tunnel vision over thinking "building hardware" is what they need to do, but unless you intend to make a piece of hardware which perfectly emulates a device which is already supported out of the box (Which makes emulating HD-20 the *only* choice if you insist on keeping the 64k ROMs) you're doomed to accomplish *nothing* unless you're willing to get your hands dirty with some system-level programming.
(Well, okay, you could perfectly emulate something else like the Tecmar Macdrive if you had binary drivers for that handy, but to do that you'd need more technical information on it than is likely was every released to build your emulator, the same problem as the HD-20. Really, the only way to practically move forward is to accept the facts as they are and buckle down to write some software. If you don't love your 128K Macintosh enough to do that then why not just seal it in a glass case and be done with it? If no one's writing software for a computer platform then by definition it's "history". Time to move on.)