Epson Stylus C40UX, Service Manual

Page: 14 / 125

Stylus C40UX/C40SX/C20UX/C20SX Revision B
PRODUCT DESCRIPTION INTERFACE 14
Signal level : TTL compatible (IEEE-1284 level 1 device)
Connector pin assignment and signals :
Parameter Minimum Maximum Parameter Minimum Maximum
tsetup 500 ns - treply 0 -
thold 500 ns - tack 500 ns 10 us
tstb 500 ns - tnbusy 0 -
tready 0 - tnext 0 -
tbusy - 500 ns
tt-out* - 120 ns * Rise and fall time of every output signals
tt-in** - 200 ns ** Rise and fall time of every input signals
***Typical time of tack is shown below.
Parallel I/F mode typical time of tack
High speed 2us
Normal speed 4usror
Parameter Minimum Maximum Condition
VOH* - 5.5 V * A low logic level on the
Logic H signal is.
2.0 V or less when the
printer is powered off and
this signal is equal or
exceeding 3.0V when the
printer is powered on.
The receiver shall provide an
impedance equivalent to 7.5
K ohm to ground
is.
VOL* -0.5 V -
IOH* - 0.32 mA VOH = 2.4 V
IOL* - 12 mA VOL = 0.4 V
CO - 50 pF
VIH - 2.0 V
VIL 0.8V -
IIH - 0.32 mA VIH = 2.0 V
IIL - 12 mA VIL = 0.8 V
CI - 50 pF
Pin No.
Signal Name
Return
GND pin In/Out Functional description
1 -STROBE 19 In
The strobe pulse. Read-in of data is
performed at the falling edge of this pulse.
2 DATA0 20 In The DATA0 through DATA7 signals
represent data bits 0 to 7, respectively.
Each signal is at high level when data is
logical 1 and low level when data is logical 0.
3 DATA1 21 In
4 DATA2 22 In
5 DATA3 23 In
6 DATA4 24 In
7 DATA5 25 In
8 DATA6 26 In
9 DATA7 27 In
10 -ACKNLG 28 Out
This signal is a negative pulse indicating that
the printer can again accept data.
11 BUSY 29 Out
A high signal indicates that the printer cannot
receive data.
12 PE 28 Out A high signal indicates paper-out error.
13 SLCT 28 Out
Always at high level when the printer is
powered on.
14 -AFXT 30 In Not used.
31 -INIT 30 In
The falling edge of a negative pulse or a low
signal on this line causes the printer to
initialize. Minimum 50 us pulse is necessary.
32 -ERROR 29 Out A low signal indicates printer error condition.
36 -SLIN 30 In Not used.
18 Logic H - Out Pulled up to +5 V via 3.9 K ohm resistor.
35 +5V - Out Pulled up to +5 V via 3.3 K ohm resistor.