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Signal Definitions
(Continued)
2.4.12 Parallel Port Interface Signals
Signal Name
Ball No.
Type
Description
Mux
EBGA
TEPBGA
ACK#
U3
B18
I
Acknowledge.
Pulsed low by the printer to
indicate that it has received data from the Par-
allel Port.
TFTDE+FPCICLK
AFD#/DSTRB#
AB2
D22
O
Automatic Feed.
When low, instructs the
printer to automatically feed a line after print-
ing each line. This signal is in TRI-STATE
after a 0 is loaded into the corresponding
control register bit. An external 4.7 K
pull-
up resistor should be attached to this ball.
Data Strobe (EPP).
Active low, used in EPP
mode to denote a data cycle. When the cycle
is aborted, DSTRB# becomes inactive (high).
TFTD2+INTR_O
BUSY/WAIT#
T1
B17
I
Busy.
Set high by the printer when it cannot
accept another character.
Wait.
In EPP mode, the Parallel Port device
uses this active low signal to extend its
access cycle.
TFTD3+F_C/BE1#
ERR#
AA3
D21
I
Error.
Set active low by the printer when it
detects an error.
TFTD4+F_C/BE0#
INIT#
Y3
B21
O
Initialize.
When low, initializes the printer.
This signal is in TRI-STATE after a 1 is
loaded into the corresponding control register
bit. Use an external 4.7 K
pull-up resistor.
TFTD5+SMI_O
PD7
U1
A18
I/O
Parallel Port Data.
Transfer data to and from
the peripheral data bus and the appropriate
Parallel Port data register. These signals
have a high current drive capability.
TFTD13+F_AD7
PD6
V3
A20
TFTD1+F_AD6
PD5
V2
C19
TFTD11+F_AD5
PD4
V1
C18
TFTD10+F_AD4
PD3
W2
C20
TFTD9+F_AD3
PD2
W3
D20
TFTD8+F_AD2
PD1
Y1
A21
TFTD7+F_AD1
PD0
AA1
C21
TFTD6+F_AD0
PE
T3
D17
I
Paper End.
Set high by the printer when it is
out of paper.
This ball has an internal weak pull-up or pull-
down resistor that is programmed by soft-
ware.
TFTD14+F_C/BE2#
SLCT
T4
C17
I
Select.
Set active high by the printer when
the printer is selected.
TFTD15+F_C/BE3#
SLIN#/ASTRB#
W1
B20
O
Select Input.
When low, selects the printer.
This signal is in TRI-STATE after a 0 is
loaded into the corresponding control register
bit. Uses an external 4.7 K
pull-up resistor.
Address Strobe (EPP).
Active low, used in
EPP mode to denote an address or data
cycle. When the cycle is aborted, ASTRB#
becomes inactive (high).
TFTD16+
F_IRDY#