Epson EL 486UC - Manual (Page 122)

IDEhard disk drive jumpersettings
* CS(cable selection) can be jumpered for any configuration. When CSis
used, the drive is a master if pin 28 isgrounded and a slave if pin 28 is not
grounded.
Connector Pin Assignments
Parallelport connectorpin assignments (CN3)
Signal
Signalground
Signalground
Signalground
Signalground
Signalground
Signalground
Signalground
*Active low logic
Specifications A-11