JP 500 (260-2950) Pinouts Faxback Doc. # 3645
Printer Interface
Host Clk/(nSTROBE) 01 ->
DATA BIT 0 02 ->
DATA BIT 1 03 ->
DATA BIT 2 04 ->
DATA BIT 3 05 ->
DATA BIT 4 06 ->
DATA BIT 5 07 ->
DATA BIT 6 06 ->
DATA BIT 7 09 ->
PtrClk/(nACK) 10 <-
PtrBusy/(BUSY) s 11 <-
AckDataReq/(PERROR) 12 <-
XFlag/(SELECT/ONLINE) 13 <-
HostBusy/(nAUTOFD) 14 ->
NC 15
LOGIC GROUND 16
CHASSIS GROUND 17
NC 18
19 SIGNAL GROUND/(Ret Pin 1)
20 SIGNAL GROUND/(Ret Pin 2)
21 SIGNAL GROUND/(Ret Pin 3)
22 SIGNAL GROUND/(Ret Pin 4)
23 SIGNAL GROUND/(Ret Pin 5)
24 SIGNAL GROUND/(Ret Pin 6)
25 SIGNAL GROUND/(Ret Pin 7)
26 SIGNAL GROUND/(Ret Pin 8)
27 SIGNAL GROUND/(Ret Pin 9)
28 GROUND/(Ret Pins 10, 12, 13)
29 GROUND/(Ret Pins 11, 32)
30 GROUND/(Ret Pins 14, 31, 36)
31 nINIT
32 nDataAvail/(nFAULT)
33 LOGIC GROUND
34 NC
35 NC
36 1284 Active/(nSELECTIN)
Connector Pins and Corresponding Signals
PIN SIGNAL SIGNAL DESCRIPTION
DIRECTION
1 to printer nSTROBE (HostClk)
Signal, valid at logic level 0, used to
transfer data to the printer.
2-9 to printer DATA BIT 0 - 7
Data transmission bus.
Data 7 is the most significant bit.
10 from printer nACK (PtrClk)
Set at 0 and then at 1 to request
a data byte from host.
11 from printer BUSY (PrtBusy)
Set at 1 to indicate that the printer is
not ready to receive data.
12 from printer PERROR (AckDataReq)
Set at 1 to indicate that the printer
is out of paper.
13 from printer ON LINE (Xflag)
Set at 1 to indicate that the printer is
ON LINE.
This signal is also handled using command
code ESC Q (printer deselection).
14 to printer nAUTOFD (HostBusy)
When set at 0, indicates that a CR is
added to each LF received.
16 --- LOGIC GROUND
Logic ground level (O V).
17 --- FRAME GROUND
(Printer earthed through host).
19-30 --- SIGNAL GROUND
Twisted pair return lines.
31 to printer nINIT.
Hardware printer reset.
32 from printer nFAULT (nDataAvail.)
Set at 0 when the printer OFF LINE or an
error has occurred.
33 --- LOGIC GROUND
Logic ground level (O V).
36 to printer nSELCTIN
Set low by host to select printer.
Command codes DC1/DC3 are handled only
when the signal is at level 1.
Slow Down Mode
To avoid "time-out" problems with MS-DOS operating systems, the printer
automatically reduces the reception speed when the line buffer is almost
full. In this situation, the printer accepts only one character every two
seconds from the line, thus guaranteeing that there will be no reception
interruption for time-out. Once the data has been unloaded by a print
operation, the reception speed will return to its normal value.
(br/all-12/13/94)