TL;DR - I am attempting to convert a keyboard & trackpad from an early 2013 Macbook Pro retina (a1398) into a standalone usb keyboard & trackpad that can be used with any modern laptop. As someone with minimal soldering and electronics experience, I could use some guidance!
Steps I've taken so far:
- Researched to see if this is even possible -- looks like the answer could be 'yes' based on some examples seen around the web
- Tried to find someone I could hire to do this (no luck thus far... hence why I'm here)
- Recently downloaded the a1398 schematics with the 820-3332-A board and fed it into some chatbots to potentially teach me how to do it myself (schematics link: https://f.ch1p.io/rjHAmTOU/820-3332-a.pdf)
Chatbot Summary of Instructions -> could use help determining if this would work
- Isolation: Open up the case and remove the R5701 & R5702 resistors -> Ensures the MacBook's PCH doesn't interfere with whatever end computer I connect it with.
- Data: Solder the Green (D+) and White (D-) wires of the USB cable to the connector side of those R5701 & R5702 resistor pads -> Corresponds to the 'USB_TPAD_P' and 'USB_TPAD_N' connections (Keyboard + trackpad data signals are combined via IPD cable)
- Power: Solder the Red (5V) wire of the USB cable to the L5700 pad leading to the connector -> this small inductor/ferrite bead provides 5V to the PP5V_S4_TPAD rail via L5700, allowing the trackpad's circuitry to manage internal power needs
- Ground: Solder the Black wire (GND) to the metal ears or shield of the J5800 connector -> ensures data signals are clean and will be recognized by an external computer
NOTE: In case you're wondering why I'm doing this...
- I have chronic myofascial pain in my upper extremities. This Macbook Pro model allowed me to go for long periods of time without pain. Having tried dozens of newer laptop models for Mac, Windows, and Chromebook, I have yet to find one with a keyboard/trackpad that performed as well for my pain as the MBP a1398. I could really use some help on how to do this myself.
LLMs are pretty much worthless when it comes to electronics. I guess that means that hardware engineers all along really were smarter than software people...
The keyboard and trackpad on this model are USB based according to the schematics. The top cover (where the keyboard and trackpad are installed) has a flex printed circuit with a Cypress PSOC1 microcontroller, which handles key scanning and communication with the multitouch trackpad (called "Z2"). It communicates over a USB 2.0 connection to the main logic board.
From this it's obvious that you don't need any part of the logic board for your project. Use the top cover only (once the battery is removed). You will need to source the right kind of FPC connector to plug the top cover into, and its pinout to supply power and other signals. Some electronics design experience will be needed to provide the right kind of power supply, level converters, and protection devices so it can be used in an external USB environment.
From there the software side remains. The USB protocol spoken by the keyboard+trackpad may be proprietary and not USB HID compatible without some massaging.
Incidentally, have you ever tried an ergonomic keyboard like a Maltron or Kinesis?
USB information from the keyboard/trackpad:
Apple Internal Keyboard / Trackpad:
Product ID: 0x0262
Vendor ID: 0x05ac (Apple Inc.)
Version: 2.22
Speed: Up to 12 Mb/sec
Manufacturer: Apple Inc.
Location ID: 0x1d182000 / 4
Current Available (mA): 500
Current Required (mA): 40
The hardware solution of this problem is very complicated. This is why you should look into an existing software solution, like Universal Control or Typeeto.
Those look like better options.
There were remote-control apps on other platforms going back a long time, like X2VNC and Teleffect. The drawback is that you need a compatible program running on both the client and the host, and there can be some security issues when TCP-IP is used for keyboard input.
Thanks for all of these thoughtful responses. I have tried various remote controller software over the years (Synergy in particular), but ran into a couple of core issues:
So, a standalone USB device bypasses many of these issues because
Also, I had looked into Universal Controller previously, and unfortunately, it only works with Macbook Pro models that are from 2016 or newer.
So that is what keeps brings me back to DIY standalone USB / Keyboard method. While it may seem like the worst, most complex route at first glance—it's actually the most viable.
I just need to know exactly how to accomplish it, which I can't seem to find anywhere.
According to this Reddit thread, you can install Universal Control on a mid 2012 MacBook Air using something called Open Core Legacy Patcher. (See all comments made by John_val.)
Remote control apps over TCP/IP are not an option. You need something that will do only the keyboard and mouse (trackpad) over Bluetooth, like Universal Control.
@CVT - this i definitely worth a shot, thanks for the tip! Will give it a try and report back once I have a chance to properly test.
I can recommend the Open Core Legacy Patcher as a great way to run more modern stuff on older Mac hardware. I used it to install macOS 11.7.10 on my 2009 iMac, and it runs seamlessly.
Will definitely look into the Open Core Legacy Patcher as well, thank you! Do you happen to know if there's a cutoff for it? you mentioned using Big Sur, but am curious if you could go even newer there in theory
Yes, you can. I don’t know what the cutoff might be in your case, but I know I had the option of installing macOS 12 or 13 a few years back when I did 11, but I stuck with 11 because it had what I needed.
Just this morning, on same said 2009 iMac running 11.7.10, I got a notification from Software Update stating that there was an update available for my machine. It was for Tahoe/26.4.1. I didn’t try to install it, but the fact it popped up at all suggests it might work.
Amazing! I went through the Youtube tutorial from CVT's Reddit link and the instructions seemed fairly straightforward. Will report back once I've had a chance to attempt.