Brother 950i

Hacking the Brother 950i knitting machine

Also known as replacing the Brother FB100 Disk Drive with a USB FTDI cable to a Laptop computer. This will only work if your Brother knitting machine has a disk port. Daisy Knits has a fabulous chart that will confirm whether your KM has a disk port (930, 940, 950i, 965i and 970).

Each model has a different memory size, so the python scripts have to be adapted for each model.
Several people (Becky SternSteve Conklin and others) have, over the years, developed a Brother disk emulator and python scripts in order to be able to load patterns in to the Brother 930 knitting machine. The Brother 930 is a USA-only model. I am in the UK, and the nearest equivalent is the Brother 950i. I also wanted to add an 'Aunty Marion'-friendly front-end that would also speed up the process for demonstrating at Maker Faire.  Yes, there are other projects out there, but this is my favourite, as I can mess about with it, and adapt it to different uses.

I have a Brother 950i. Therefore, I have modified Becky Stern's 930 adafruit scripts to work with a 950i. The files are stored on GitHub, where you can also find copies of blank patterns of all sizes (thanks to the fabulous folks at London Hackspace), a GUI front-end I use for scanning images at Maker Faire, and a multicolour version used to make Kevin's Christmas Vest.

The steps involved are:

1. You need a Brother 950i knitting machine. They are no longer made, so keep an eye on eBay, your local knitting machine shop, and the classifieds page of the Guild of Machine Knitters.
2. Make up an FTDI USB cable.
3. Install the software

  • Install Python 2.7.3
  • Install Python Image Library (PIL) 1.1.7
  • Install pyserial 2.6 (remembering to run the [ install] command)
  • Download Brother 950i version of the software from Github and unzip to a suitable folder (c:\Brother950i)
  • Edit line 287 of, change timeout=1 to timeout=5.
  • Get an FTDI cable (such as this FTDI cable from Cool Components)
  • Invert TTL, and convert serial end from flat 8 to 2x4
  • Download VPC driver for FTDI cable (ie. CDM 2.08.28 WHQL Certified)
  • Plug in the USB cable to computer, and when pop-up appears, point driver installer at VCP driver.
  • Install the CoreUtils-5.3.0.exe from to provide CAT command (concatenate) used by the python scripts
  • Add CoreUtils BIN folder to PATH.
    • Right-click My Computer, select Properties
    • Advanced tab
    • Environment variable button
    • Under System Variables, select Path
    • Click the Edit button
    • Add to the end of the text: C:\Program Files\GnuWin32\bin\;
  • Reboot.
  • Check that you downloaded the blank pattern files from Github (this folder). 
  • Make copy of a 60x150 blank pattern folder called mypicture
  • Change to original 60x150 blank pattern folder and CAT together all the file-*.dat files to 60x150.dat
  • Copy 60x150.dat up one folder
  • Create image file that is monochrome 1-bit bitmap, 60 pixels wide by 150 pixels high. Paint is good for this as it has the Save As option of monochrome. With this software it uses black as the main yarn colour, and white as the contrast yarn colour.
  • Insert the image in to the blank pattern:
    • 60x150.dat 901 mypicture.bmp mypicture.dat
    • mypicture.dat
  • Copy to created 00.dat ... 31.dat files in to the /mypicture/ folder
  • Start emulator:
    • mypicture COM4

On KM:

  • Load from disk (551, M)
  • Choose disk pattern (1, M)
  • Let pattern load, the KM will beep when finished.
  • Load the pattern (M, 901)
  • Move to line 1 of pattern
  • Knit!

4. Optional: Install a Windows GUI front-end.

Starting at Maker Faire UK in 2013 I've had a stand set up with a Brother 950i knitting machine, a scanner, a laptop, and a large pile of paper, chunky markers and pens. Visitors to the show can draw a picture, then scan it in to the laptop, convert it in to a knitting pattern, that I then knit on the machine (and they can have a go too!).

To speed up the process (down to about 30 minutes from scan to completed cast-off), I wrote a little desktop app that loads the latest image from the scanner, converts the image, loads the disk emulator with the output disk image. If you would like to have a play, then please do. It is a work in progress and makes some assumptions (see the readme.txt file). Download Image To Knitting Machine from GitHub.

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