Service manual

EPSON Stylus PHOTO 870/1270 Revision B
PRODUCT DESCRIPTIONS Interface 21
1.3 Interface
The EPSON Stylus PHOTO 870/1270 provide USB and parallel interface as
standard.
1.3.1 Parallel Interface (Forward Channel)
"
Transmission mode: 8 bit parallel, IEEE-1284 compatibility mode
"
Synchronization: By STROBE pulse
"
Handshaking: By BUSY and ACKNLG signal
"
Signal level: TTL compatible level
"
Adaptable connector: 57-30360 (amphenol) or equivalent
Figure 1-7. Data Transmission Timing
Typical timing for tack is shown below.
DATA
data byte n
data byte n+1
-STROBE
BUSY
-ACKNLG
thold
tsetu
tstb
tread
tbusy
treply
tack
tnbus
tnext
Table 1-10. Parameters
Parameter Minimum Maximum
tsetup 500ns -
thold 500ns -
tstb 500ns -
tready 0 -
tbusy - 500ns
tt-out
*1
*1:
Rise and fall time of every output signal.
- 120ns
tt-in
*2
*2:
Rise and fall time of every input signal.
- 200ns
treply 0 -
tack 500ns 10us
tnbusy 0 -
tnext 0 -
Table 1-11. Typical Time of Tack
Parallel I/F Mode Typical Time of tack
High Speed 1us
Normal Speed 3us