The timers use a Serial Cable. The computer will need to have a serial port to accept this cable.
It is always better to have a built-in serial port, but all-in-one PCs often do not have them. For these you can use a serial-to-USB adapter to convert the signal.
We strongly suggest using one of these two Prolific brand USB to RS-232 DB9 Serial Adapter (PL-2303HX Rev D chipset) models depending on the port or serial cable on the timer. It will be dependent on the small screws and lugs at the end of the cables.
Staples USB to Serial Adapter, Male to Male (29764) https://www.staples.com/Staples-1-USB-to-Serial-Adapter-Black/product_2093905
Plugable USB TO RS-232 DB9 Serial Adapter https://www.amazon.com/Plugable-Adapter-Prolific-PL2303HX-Chipset/dp/B00425S1H8/
Whichever is purchased, always make sure that the pins, lugs, and screws for the adapter match what you are plugging it in to.
For Windows 8 and 10, the adapter must be a Rev D chipset. We have had very good success with the model above and other models may not work with newer operating systems.