EPP was created in 1991
to permit up to 2 Mbps data transfer, and was intended primarily for non-printers. ECP was created in
1992 to permit higher speed printer communications. IEEE1284 was created in 1994 to combine EEP and ECP,
and relies on the host to determine which standard to use.
Strobe |
1 |
1 |
Write |
1 |
Host CLK |
1 |
Data 0 |
2 |
2 |
Data 0 |
2 |
Data 0 |
2 |
Data 1 |
3 |
3 |
Data 1 |
3 |
Data 1 |
3 |
Data 2 |
4 |
4 |
Data 2 |
4 |
Data 2 |
4 |
Data 3 |
5 |
5 |
Data 3 |
5 |
Data 3 |
5 |
Data 4 |
6 |
6 |
Data 4 |
6 |
Data 4 |
6 |
Data 5 |
7 |
7 |
Data 5 |
7 |
Data 5 |
7 |
Data 6 |
8 |
8 |
Data 6 |
8 |
Data 6 |
8 |
Data 7 |
9 |
9 |
Data 7 |
9 |
Data 7 |
9 |
Acknowledge |
10 |
10 |
Interrupt |
10 |
Periph CLK |
10 |
Busy |
11 |
11 |
Wait |
11 |
Periph ACK |
11 |
Paper End |
12 |
12 |
Spare |
12 |
Ack Reverse |
12 |
Select |
13 |
13 |
Spare |
13 |
X-Flag |
13 |
Auto Line Feed |
14 |
14 |
Data Strobe |
14 |
Host ACK |
14 |
Error |
32 |
15 |
Spare |
15 |
Periph Request |
15 |
Initialize Printer |
31 |
16 |
Reset |
16 |
Reverse Request |
16 |
Select Input |
36 |
17 |
Address Strobe |
17 |
1284 Active |
17 |
Strobe Return |
19 |
18 |
Ground |
18 |
Ground |
18 |
Data 0 Return |
20 |
19 |
Ground |
19 |
Ground |
19 |
Data 1 Return |
21 |
19 |
Ground |
20 |
Ground |
20 |
Data 2 Return |
22 |
20 |
Ground |
21 |
Ground |
21 |
Data 3 Return |
23 |
20 |
Ground |
22 |
Ground |
22 |
Data 4 Return |
24 |
21 |
Ground |
23 |
Ground |
23 |
Data 5 Return |
25 |
21 |
Ground |
24 |
Ground |
24 |
Data 6 Return |
26 |
22 |
Ground |
25 |
Ground |
25 |
Data 7 Return |
27 |
22 |
Acknowledge
Return |
28 |
24 |
Busy Return |
29 |
23 |
Paper End Return |
28 |
24 |
Select Return |
28 |
24 |
Auto Line Feed Return |
30 |
25 |
Error Return |
29 |
23 |
Initialize Printer Return |
30 |
25 |
Select Input Return |
30 |
25 |
Shield |
33 |
N/C |
N/C |
34 |
N/C |
N/C |
35 |
N/C |
|