An anonymous reader pinged us about an issue that affects people who jumped onto the latest-and-greatest OS from the Apple gardens: USB devices that stop working due to the FTDI-based USB solution. At its core appears to be that the built-in FTDI driver provided by Apple (AppleUSBFTDI.dext) only supports FTDI chips which provide the standard FTDI vendor and product ID (e.g. 0x0403 and 0x6001 respectively for the FT232R). Many products however set a custom product ID (PID) to differentiate their device, though in the thread some mention that there are driver issues even with the default VID/PID combination.
Over the past years, Apple has been restricting and changing the way kernel extensions (KExt) and driver extensions (DExt) are handled. As these FTDI chips are often used for virtual com port (VCP) purposes, such as with Arduino boards and USB-TTL adapters, this is a rather cumbersome issue that would affect anyone using Big Sur in combination with such a hardware device.
So far only the FTDI team has been somewhat responsive based on the support forum thread, with Apple seemingly rather silent on the issue.
There’s a sleek form factor for desktop computers known as an “all-in-one” that enrobes a computer in a monitor. While the convenience of having all your computing in a neat package has some nice benefits, it comes with an unfortunate downside. Someday the computer inside is going to be old and outdated in comparison to newer machines. While a new OS goes a long way towards breathing life into an old machine, [Thomas] has decided to take the path less travelled and converted an old iMac all-in-one into a discrete monitor.
The iMac in question is the 20″ iMac G5 iSight (A1145) with an LG-Philips LM201W01-STB2 LCD panel. Looking back, [Thomas] would recommend just ordering an LCD driver controller kit from your favourite auction house. But for this particular modification, he decided to do things a little bit more manually and we’re quite glad he did.
Luckily for [Thomas], the panel supports TMDS (which both DVI and HDMI are compatible with). So the next step was to figure out the signalling wires and proper voltages. After some trouble caused by a mislabeled power line on the iMac PCB silk-screen (12v instead of 3.3v), he had all the wires identified and a plan starting to form. The first step was a circuit to trick the inverter into turning on with the help of a relay. The female HDMI plug with a breakout board was added and sticks out through the old firewire port. The minuscule wires in the display ribbon cable to the monitor were separated and soldered onto with the help of [Thomas’] daughter’s microscope. Resistances were checked as HDMI relies on impedance matched pairs. To finish it off, an old tactile toggle switch offers a way to turn the monitor on and off with a solid thunk.
We love seeing old hardware being repurposed for new things. This project nicely complements the iMac G4 Reborn With Intel NUC Transplant we saw earlier this year, as they both try to preserve the form factor while allowing a new computer to drive the display.
Anyone who pokes around old electronics knows that age is not kind to capacitors. If you’ve got a gadget with a few decades on the clock, there’s an excellent chance that some of its capacitors are either on the verge of failure or have already given up the ghost. Preemptively swapping them out is common in retrocomputing circles, but what do you do if your precious computer has already fallen victim to a troublesome electrolytic?
That’s the situation that [Ronan Gaillard] recently found himself in when he booted up his Mac SE/30 and was greeted with a zebra-like pattern on the screen. The collected wisdom of the Internet told him that some bad caps were almost certainly to blame, though a visual inspection failed to turn up anything too suspicious. Knowing the clock was ticking either way, he replaced all the capacitors on the Mac’s board and gave the whole thing a good cleaning.
Unfortunately, nothing changed. This caught [Ronan] a bit by surprise, and he took another trip down the rabbit hole to try and find more information. Armed with schematics for the machine, he started manually checking the continuity of all the traces between the ROM and CPU. But again, he came up empty handed. He continued the process for the RAM and Glue Chip, and eventually discovered that trace A24 wasn’t connected. Following the course it took across the board, he realized it ran right under the C11 axial capacitor he’d replaced earlier.
Suddenly, it all made sense. The capacitor must have leaked, corroded the trace underneath in a nearly imperceptible way, and cut off a vital link between the computer’s components. To confirm his suspicions, [Ronan] used a bodge wire to connect both ends of A24, which brought the 30+ year old computer roaring back to life. Well, not so much a roar since it turns out the floppy drive was also shot…but that’s a fix for another day.
Getting the LCD panel and Raspberry Pi 4 to fit into the slim 3D printed case took considerable coaxing. In the video after the break, you can see [Michael] strip off any unnecessary components that would stand in his way. The LCD panel had to lose its speakers and buttons, and the Pi has had its Ethernet and USB ports removed. While space was limited, he did manage to squeeze an illuminated resin-printed Apple logo into the lid of the laptop to help sell the overall look.
The bottom half of the machine has a number of really nice details, like the fan grill cut from metal hardware cloth and a functional “MagSafe” connector made from a magnetic USB cable. The keyboard PCB and membrane was liberated from a commercially available unit, all [Michael] needed to do was model in the openings for the keys. Since the keyboard already came with its own little trackpad, the lower one is just there for looks.
Speaking of which, to really drive home the Apple aesthetic, [Michael] made the bold move of covering up all the screws with body filler after assembly. It’s not a technique we’d necessarily recommend, but gluing it shut would probably have made it even harder to get back into down the line.
We know that some in the audience will take issue with calling a Raspberry Pi in a 3D-printed case the “World’s Smallest iMac”, but you’ve got to admit, [Michael Pick] has certainly done a good job recreating the sleek look of the real hardware. While there might not be any Cupertino wizardry under all that PLA, it does have a properly themed user interface and the general aversion to external ports and wires that you’d expect to see on an Apple desktop machine.
The clean lines of this build are made possible in large part by the LCD itself. Designed specifically for the Raspberry Pi, it offers mounting stand-offs on the rear, integrated speakers, a dedicated 5 V power connection, and a FFC in place of the traditional HDMI cable. All that allows the Pi to sit neatly on the back of the panel without the normal assortment of awkward cables and adapters going in every direction. Even if you’re not in the market for a miniature Macintosh, you may want to keep this display in mind for your future Pi hacking needs.
Despite this clean installation, the diminutive Raspberry Pi was still a bit too thick to fit inside the 3D-printed shell [Michael] designed. So he slimmed it down in a somewhat unconventional, but admittedly expedient, way. With a rotary tool and a steady hand, he simply cut the double stacked USB ports in half. With no need for Ethernet in this build, he bisected the RJ-45 connector as well. We expect some groans in the comments about this one, but it’s hard to argue that this isn’t a hack in both the literal and figurative sense.
We really appreciate the small details on this build, from the relocated USB connectors to the vent holes that double as access to the LCDs controls. [Michael] went all out, even going so far as to print a little insert for the iconic Macintosh logo on the front of the machine. Though given the impressive work he put into his miniature “gaming PC” a couple months back, it should come as no surprise; clearly this is a man who takes his tiny computers very seriously.
Like many before it, this Mac 512K case was originally slated to get turned into a kitschy desktop aquarium. But its owner never found the time to take on the project, and instead gave it to [Tony Landi]. Luckily, he decided to forgo the fish and instead outfit the case with a new LCD display and Raspberry Pi to emulate Mac OS 7.5.
In the video after the break, [Tony] walks viewers through the process of mounting the new components into the nearly 30+ year old enclosure. Things are naturally made a lot easier by the fact that the modern electronics take up a small fraction of the Mac’s internal volume. Essentially the only things inside the case are the 10 inch 4:3 LCD panel, the Raspberry Pi, and a small adapter that turns the Mac’s pre-ADB keyboard into standard USB HID.
[Tony] had to design a 3D printed adapter to mount the modern LCD panel to the Mac’s frame, and while he was at it, he also came up with printable dummy parts to fill in the various openings on the case that are no longer necessary. The mock power switch on the back and the static brightness adjustment knob up front are nice touches, and the STLs for those parts will certainly be helpful for others working on similar Mac conversions.
With the hardware out of the way, [Tony] switches gears and explains how he got the emulated Mac OS environment up and running on the Raspberry Pi. Again, even if you don’t exactly follow his lead on this project, his thorough walk-through on the subject is worth a watch for anyone who wants to mess around with Apple software from this era.
Apple computers will be moving away from Intel chips to its own ARM-based design. An interesting thing about Apple as a company is that it has never felt the need to tie itself to a particular system architecture or ISA. Whereas a company like Microsoft mostly tied its fortunes to Intel’s x86 architecture, and IBM, Sun, HP and other giants preferred vertical integration, Apple is currently moving towards its fifth system architecture for its computers since the company was formed.
What makes this latest change possibly unique, however, is that instead of Apple relying on an external supplier for CPUs and peripheral ICs, they are now targeting a vertical integration approach. Although the ARM ISA is licensed to Apple by Arm Holdings, the ‘Apple Silicon’ design that is used in Apple’s ARM processors is their own, produced by Apple’s own engineers and produced by foundries at the behest of Apple.
In this article I would like to take a look back at Apple’s architectural decisions over the decades and how they made Apple’s move towards vertical integration practically a certainty.