Recently I see a lot of posts about good cables/adapters to connect Newtons with NCX on new MacOS (10.13, 10.14, and newer). So, I wish to share my experience and (I believe) a simple solution.
JANUARY 2022: DIRECT USB-TO-SERIAL CABLE
The newest option is to use a USB-to-serial cable I’ve designed and ordered from the Chinese manufacturer. This cable is built based on the same original FTDI FT232R chip and dedicated voltage converter to deliver proper voltage for miniDIN 8-pin end. This cable is working like a charm on all modern macOS (even Monterey) and I get a report from Patrick Longinotti that old PPC OSX and even classic OS (8-9 with USB support) can work with my cable!
So, this cable is a direct solution for all Newtons with miniDIN 8-pin serial port, and for Newton 2×00 you still need an InterConnect dongle (but you need it anyway).
NOVEMBER 2021: USB-TO-RS232 DONGLE
This dongle is available on Amazon and works perfectly with modern Macs (original FTDI FT232R chip). Obviously, you will need to RS232 to miniDIN 8-pin cable for your Newton to use it with Newton.
APRIL 2021: USB-TO-RS232 CABLE
Most of the old USB to RS422 adapters have problems working with modern macOS. Usually, there is a problem with drivers or adapters freezing, etc. But some time ago I’ve found a good cable with the FTDI chipset, which DO NOT need any drivers for MacOS 10.11 and newer. This cable is made by UGREEN and has really good quality:
This cable is a USB to RS232 converter, so to connect Newton with your computer you need RS232 to RS422 cable too. But this second one is a standard cable to connect Newton with RS232 (Windows standard). Most of the Newton users should have that cable. If not, you need to buy it or make it on your own. Here you have pins connection diagram:
Then you need the NCX app, which you can download from here: https://newtonresearch.org/connection/ After installation and connecting the UGREEN cable to your macOS, you will see a separate port in NCX app settings. You can connect your Newton with a modern Mac now.
IMPORTANT INFO ABOUT NCX: Sometimes NCX does not respond after closing the connection with Newton. In this case, you need to (1) close the NCX connection window, (2) close NCX, (3) open NCX, (4) and open new window (New connection – cmd+N). It is a small glitch in the NCX app.