HP 1100A - Manual (Page 21)

EN Printing a self-test page 21
Printing a self-test page
Among other items, a self-test page provides all of the printer
configuration settings, scanner attachment verification, a sample of
the print quality, and provides information for printer page counts as
well as scan and copy page counts. A self-test page can also help
you verify the printer is printing correctly.
To print a self-test page, press and release the Go button on the
printer control panel while the printer is in the Ready state. If the
printer is in PowerSave mode, press and release the Go button once
to awaken it, and then press and release the Go button a second
time.