Filter
Top Products
Chapter 3 Hardware
44 Reference Manual XTX 820
Pin # Signal Description
60 ERR*
HDSEL*
Parallel Error – This is a status output signal from the printer. A low state
indicates an error condition on the printer.
Floppy Head Select – Selects the side for Read/Write operations (0 = side 1,
1 = side 0)
61 IRTX IR Transmit Data (HPSIR or ASKIR)
62 PD6 Parallel Port Data 6 – This signal (0 to 7) provides a parallel port data signal
and is the printer data MSB.
63 RXD2 Receive Data 2 – Serial port 2 receive data in.
64 INIT*
DIR*
Parallel Initialize* – This signal initializes the printer. Output in standard
mode, I/O in ECP/EPP mode.
Floppy Direction – Direction of head movement (0 = inward motion,
1 = outward motion).
65, 66 GND Ground
67 RTS2*
Request To Send 2 – Indicates Serial port 2 is ready to transmit data. Used
as hardware handshake with CTS2 for low level flow control.
68 PD5 Parallel Port Data 5 – Refer to pin-58 and 80 for more information.
69 DTR2*
Data Terminal Ready 2 – Indicates Serial port 1 is powered, initialized, and
ready. Used as hardware handshake with DSR2 for overall readiness.
70 SLCTIN*
STEP*
Select In – This output signal is used to select the printer. I/O pin in
ECP/EPP mode.
Floppy Step – Low pulse for each track-to-track movement of the head.
71 DCD2*
Data Carrier Detect 2 – Indicates external serial device is detecting a carrier
signal (i.e., a communication channel is currently open). In direct connect
environments, this input is driven by DTR2 as part of the DTR2/DSR2
handshake.
72 PD4
DSKCHG*
Parallel Port Data 4 – Refer to pin-58 and 80 for more information.
Floppy Disk Change – Senses the drive door is open or the diskette has been
changed since the last drive selection.
73 DSR2* Data Set Ready 2 – Indicates external serial device is powered, initialized,
and ready. Used as hardware handshake with DTR2 for overall readiness.
74 PD3
RDATA*
Parallel Port Data 3 – Refer to pin-58 and 80 for more information.
Floppy Read Data – Raw serial bit stream from drive for read operations.
75 CTS2* Clear To Send 2 – Indicates external serial device is ready to receive data.
Used as hardware handshake with RTS2 for low level flow control.
76 PD2
WP*
Parallel Port Data 2 – Refer to pin-58 and 80 for more information.
Floppy Write Protect – Senses the diskette is write protected.
77 TXD2 Transmit Data 2 – Serial port 2 transmit data out
78 PD1
TRK0*
Parallel Port Data 1 – Refer to pin-58 and 80 for more information.
Floppy Track 0 – Sense detects the head is positioned over track 0.
79 RI2* Ring Indicator 2 – Indicates external serial device is detecting a ring
condition. Used by software to initiate operations to answer and open the
communications channel.