HP 400 - Manual (Page 39)

2-4 Installation and Configuration
Centronics Parallel Pinout Information
Figure 2-2. Centronics Parallel Interface Connector
1. Active low.
Table 2-2. Centronics Parallel Interface Pinout Information
Pin
Number Pin ID Description
1 Strobe
1
A low pulse causes the printer to read one byte of data.
2 - 9 Data 0 - Data 7 These pins are the data lines. Data 0 is the least significant bit (LSB).
10 Acknowledge
1
The printer sends a low pulse to indicate that it has accepted a byte of data and is ready
for more data.
11 Busy The printer sends a high logic level to indicate to the computer that it cannot receive data
due to data entry, a full buffer, or error status.
12 Paper Error The printer sends a high logic level to indicate to the computer that it is out of paper.
13 Ready The printer sends a high logic level to indicate to the computer that it is in an online
condition. The printer sends a low logic level to indicate that it is offline or that the input
buffer is full.
16 Signal Ground Signal interface ground.
17 Chassis Ground Chassis ground.
18 +5 V The printer outputs a +5 volt high logic level through a 2.2K ohm resistor.
19 - 30 Ground These pins are tied to signal ground.
31 Reset/Input Clear
1
A low pulse sent by the computer resets the printer and clears the print buffer. The reset
occurs on the trailing edge of the pulse.
32 Error
1
The printer sends a low logic level to the computer to indicate that it is in an error state.
18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1
36 35 34 33 32 31 30 29 28 27 26 25 24 23 22 21 20 19
Ground
Strobe (STR)
Data 0
Data 2
Data 3
Data 4
Data 5
Data 6
Data 7
Data 1
Acknowledge (ACK)
Busy
Paper Error (PE)
Ready
Signal Ground
Chassis Ground
+5V
Error (ERR)
Reset/Input Clear