Appendix A Centronics Parallel Interface
Oki Data CONFIDENTIAL
44983601TH Rev.1
AppendixA-2/
(3) ListofParallelI/FSignals
• ConnectorPinAllocation
(Note1) Thewordinparenthesesisasignalnameofthenibblemode.
(Note2) Onlythefunctionofthecompatiblemodeisdescribed.
(Note3) This printer supports the nibble ode of IEEE std 1284-1994 prescribed by Institue of Electrical and
ElectronicEngineers.Whenusingcomputersorcablesnotcompatiblewiththisstandard,unexpected
operationsmayoccur.
(4) SignalLevel
•LOW :0Vto+0.4V
•HIGH:+2.4Vto5.0V
PinNo SignalName Direction Function
1 nStrobe(HostClk) TOPRINTER Pulsetoreaddata.
Thedataisreadattheposteriorborder.
2 DATA1 TOPRINTER 8-bitparalleldata
Thehighlevelis“1”andthelowlevelis“0”.
3 DATA2
4 DATA3
5 DATA4
6 DATA5
7 DATA6
8 DATA7
9 DATA8
10 nAck(PtrClk) FROMPRINTER Signaltoshowthatthedatareceptioniscompleted.
Itisoutputtedattheposteriorborderofthebusysignal.
11 Busy(PtrBusy) FROMPRINTER Signaltoshowwhethertheprintercanreceivedata.
Thedatacannotbereceivedatthehighlevel.
12 PError(AckDataReq) FROMPRINTER Thedevicebecomesthehighlevelwhenitoutofpaperina
selectedfeeder.
13 Select(Xag) FROMPRINTER Alwaysthehighlevel.
14 nAutoFd(HostBusy) TOPRINTER Itisusedinthebi-directionalcommunication.
15 Notused − Notconnected.
16 GND − SignalGround
17 FG − ChassisGround
18 HILEVEL FROMPRINTER Itispulledupto3.3
and+5Vintheprinter.
19~30 GND − SignalGround
31 nInit(nInit) TOPRINTER Whenthelowleveliscontinuedat50μSormore,theprinter
isinitialized.Itmaybeenabledat50μSorless.Thissignal
isignoredatthefactorydefault.
32 nFault(nDataAvail) FROMPRINTER Itbecomesthelowlevelwhentheprinterisinthealarm
status.
33 GND − SignalGround
34 Notused − NotConnected
35 HILEVEL FROMPRINTER Itispulledupto3.3
and+5Vintheprinter.
36 nSelectIn
(IEEE1284active)
TOPRINTER Itisusedinthebi-directionalcommunication.