Our switches and the concepts are demonstrated on the Serial Kill Switch video by the very popular MonroeWorld on YouTube. Check him out!
Dual IEC Kill Switch and Device Selector for Commodore Systems
The Acutis Data Dual IEC Kill Switch is a handmade, fully breaking ON-OFF-ON IEC selector for Commodore computers, disk drives, printers, ZoomFloppy setups, and modern IEC-compatible accessories.
This is the next evolution in a design direction originally inspired by the vintage KETEK Data Director. It is also the larger, more capable “big brother” of our Inline Kill Switch for Commodore C64 Ultimate C64 C128 X16 Physical IEC Drives, the compact “little brother” version for a single physical IEC device.
This dual version expands the original inline IEC kill switch concept by allowing you to connect two physical IEC devices or drives to one computer, or two computers/controllers to one IEC device. It is especially useful when you want to keep multiple IEC devices connected without constantly unplugging and reconnecting cables.
Switch left to connect one IEC side.
Switch right to connect the other IEC side.
Switch to the center OFF position to isolate both switched IEC sides. This makes the center position work like a double kill switch or dual kill switch.
Works as a Dual Drive Selector or Computer Selector
This switch can be used in either direction. Use it to choose between two IEC drives connected to one Commodore computer, or use it to share one IEC drive between two different computers or controllers.
- Select between two physical Commodore IEC drives or devices.
- Share one IEC drive between a Commodore computer and another IEC controller.
- Use with ZoomFloppy when sharing a real Commodore drive with a PC.
- Center OFF position isolates both switched sides for a clean dual kill-switch function.
A Practical C64 Ultimate IEC Bus Isolation Solution
In some C64 Ultimate setups, a connected physical IEC device may appear to interfere with the C64 Ultimate's ability to see or use its virtual drives, even when that physical device is not actively being used. The exact cause is not always obvious, but the connected device may still be affecting the IEC bus in some way, acting like an electrical load or sink on the line.
This adapter gives you a physical way to select, isolate, or share IEC connections without repeatedly unplugging cables from your computer, drive, ZoomFloppy, or other IEC-compatible hardware. It is a practical solution for this kind of poorly understood IEC bus interference, and it is also useful simply for keeping a cleaner, more flexible Commodore setup.
Fully Breaking ON-OFF-ON Switching
The main toggle switch is a 4-pole ON-OFF-ON switch. It switches the primary IEC bus lines:
In the center OFF position, both switched IEC paths are broken. That means neither side is selected, giving you a true center-off isolation position for the switched IEC lines. In practice, the OFF position acts as a double IEC kill switch or dual IEC kill switch.
The SRQ line remains connected, which is recommended for many modern IEC-compatible setups. The RESET line is controlled by the momentary push-button switch, allowing reset to be interrupted separately.
This version has no LED indicator lights, keeping the design simple while improving compatibility with a wider range of Commodore and IEC-compatible machines.
Common Ways to Use It
- One Commodore computer selecting between two physical IEC drives.
- One C64 Ultimate selecting between two real IEC devices.
- One Commodore drive shared between a Commodore computer and a ZoomFloppy-connected PC.
- One IEC printer, drive, or accessory shared between two IEC-capable systems.
- A dual kill switch for isolating connected physical IEC hardware when using a virtual IEC drive.
Available Customization Options
The following options may be available at no additional charge:
- Switch location
- Connector orientation
- Reset-line behavior, depending on the requested configuration
- SRQ-line connectivity, always connected by default and recommended for most users
Please message me after purchase if you would like a customized configuration. Some requests may not be possible due to the physical limitations of the enclosure.
Looking for something else more elaborate? Message me if you would like a similar adapter with additional ports or switches. I also build fully customized one-off solutions. I am happy to work through a design and give you a fair custom quote.
Quality and Fulfillment
Each switch is handmade to the same high quality standards people have come to expect from the Acutis Data brand, with careful assembly, clean wiring, and full testing before shipment.
These switches are made to order. After purchase, I will provide an estimated shipping date. Occasional delays may occur if supplies need to be reordered.
Every item is fully tested before shipment and guaranteed to work. If there is a problem, you will receive a replacement or a full refund.
Compatibility
Although designed with the C64 Ultimate and IEC bus isolation in mind, this switch can also be used with traditional Commodore serial IEC equipment, ZoomFloppy, and modern IEC-compatible accessories, including:
- Commodore VIC-20
- Commodore 64
- Commodore 64c
- Commodore 64 Ultimate
- Commodore 64 Ultimate Compact
- Commodore 128
- Commander X16
- ZoomFloppy
- Commodore disk drives
- Commodore printers
- Modern IEC-compatible accessories
