The CSI Connect model 400 and 400S were produced back in the 80's. This unique IEEE interface did not plug into the computer through the commonly used cartridge or user ports. Instead, this device allowed the user to access IEEE disk drives that were originally intended for the Commodore PET series of computers to be used on more modern 64/128/Plus4 computers directly through the standard IEC port. This further allowed the use of the basic functions of kernal upgrades such as JiffyDOS and PhantomDOS with IEEE drives.
Although parallel port speed is not achieved using this device, a speed boost of 2x is realized through loading and saving to IEEE connected devices.
The reverse engineering effort of the original source model 400 has been enhanced to the 400S model that came later with added features.
Enhancements include a more compact board, standard barrel connection of any power adapter rated between 7.5v and 25vdc, heat sinked power regulator, ability to switch between IEEE only, IEEE & IEC, IEC only, power LED and a far superior quality vented case that protects the IEEE connection from accidental exposure to shorting or static discharges.
Here is a photo of one of the later prototypes. The final version will also be gold plated black, with enhanced LED placement, and Commodore keyed IEEE connector as well as better placement/options for switch connectivity.