Epson Stylus Photo 720 Service Manual page 14

EPSON Stylus Photo 720 / EPSON Stylus Photo EX3
Table 1-5. Parallel I/F Specification (R-Channel)
Item
Transmission mode IEEE-1284 nibble mode
Synchronization Comply with the IEEE-1284 specification
Handshaking Comply with the IEEE-1284 specification
Logic Level TTL level (IEEE-1284-Level 1 device)
Data trans. timing Comply with the IEEE-1284 specification
Extensibility request data The printer responds affirmatively when the extensibility request
values are 00H or 04H;
00H: Request Nibble Mode Reverse Channel Transfer.
04H: Request Device ID;
Return Data Using Nibble Mode Reverse Channel Transfer
Product Description
Specification
Interface Specification
Device ID
o
When IEEE-1284.4 protocol is effective:
n
[00H] [5AH]
MFG: EPSON;
CMD: ESCPL2, BDC, D4;
MDL: Stylus[SP]Photo[SP]720;
CLS: PRINTER;
DES: EPSON[SP]Stylus[SP]Photo[SP]720;
When IEEE1284.4 protocol is NOT effective:
n
[00H] [57H]
MFG: EPSON;
CMD: ESCPL2, BDC;
MDL: Stylus[SP]Photo[SP]720;
CLS: PRINTER;
DES: EPSON[SP]Stylus[SP]Photo[SP]720;
Note: *1 For Stylus Photo EX3, MDL: Stylus[SP]Photo[SP]EX3;
DES: EPSON[SP]Stylus[SP]Photo[SP]EX3, respectively.
The connector pin assignment is described in the table below. For these signals
described in the table, use the twist pair wire and connect the return side to the signal
GND.
Table 1-6. Connector Pin Assignment and Signals (F-Channel)
Return
Pin No. Signal Name
GND Pin
1 19 HostClk
2-9 20-27 Data1-8
10 28 PtrClk
PtrBusy/
11 29
DataBit-3,7
AckDataReq/
12 28
DataBit-2,6
Xflag/DataBit-
13 28
1,5
Revision A
*1
*1
*1
*1
From Function Description
PC Host clock signal.
The DATA 1 through DATA8 signals
PC
represent data bits 1-8 respectively.
Printer Printer clock signal.
Printer busy signal and reverse channel
Printer
transfer data bit 3 or 7.
Acknowledge data request signal and
Printer
reverse channel transfer data bit 2 or 6.
X-flag signal and reverse channel
Printer
transfer data bit 1 or 5.
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