Hi,
Yes, connecting DI, DO, CLK and ground to the parallel would be all you need to do. Power the chip from a 5V power supply, using perhaps a connection from your Amiga's power supply or a micropower regulator and a battery pack to retain the time when the power is off!
Another option but more involved would be to use a micrcontroller to interface to the chip and send the time to your Amiga via the serial port. This would have a lower CPU overhead.
