The ecpp(7) driver is installed with the OS if the system being tested supports the ecpp(7) device. To run the optional printer subtest, a Centronics or ECP-mode printer must be attached to the printer port. To run the optional external loopback test, a passive loopback connector must be installed on the printer port.
The external loopback test is intended for Sun internal manufacturing use only. It requires a custom loopback connector not available to an external customer.