Epson STYLUS COLOR 480, Руководство по обслуживанию

Страница: 23 / 149

EPSON Stylus COLOR 480 Revision B
Product Description Interface Specification 23
Following lists “Notes” when using the parallel interface.
o
“Return GND pin” in the table means twist pair return and is connected to the
signal GND level.
For each signal, use the twist pair wire and connect the return side.
Also, these cables are shielded wires and it is effective means to connect to each
chassis GND in the center machine and printer for electrostatic noise.
o
Refer to the timing chart for transmission timing of each signals.
o
Do not perform data transmission ignoring -ACK or BUSY signals. (Perform the
data transmission after confirming that either -ACK or BUSY signal is Low)
o
It is possible to perform the printing test including interface circuit without using
external equipment when 8-bit data signal (2-9 pin) is set to appropriate character
code (against GND, Open=”1”, Short=”0”) and connect then forcefully to -ACK
and -STRB. However, to perform this, “I/F selection” of EEPROM must be set to
“Auto”. Also, IEEE-1284.4 packet mode must be set Off.
The figure below shows the timing chart of the parallel interface.
Figure 1-8. IEEE1284 Timing Chart
(1*): Rise and fall time of every output signals.
(*2): Rise and fall time of every input signals.
On the above timing chart, T
ack
rated period is varies depend on the Parallel I/F data
transmission speed below.
Data byte n Data byte n+1
DATA
/STROBE
BUSY
/ACKNLG
t
hold
t
setup
t
ready
t
stb
t
busy
t
reply
t
ack
t
nbusy
t
next
timechart
Table 1-9. IEEE1284 Timing Chart
Parameter Minimum Maximum
tsetup 500ns --
thold 500ns ---
tstb 500ns ---
tready 0 ---
tbusy 0 ---
tt-out (*1) --- 120ns
tt-in (*2) --- 200ns
treply 0 ---
tack 500ns 10us
tnbusy 0 ---
tnext 0 ---
Table 1-10. t
act
Typical time of T
ack
Parallel I/F Mode Typical Time
High speed 2
µ
s
Normal speed 4
µ
s