A Made IT project

Centronics

General
One of the most used printer interfaces, since every Intel/DOS/Windows based Personal Computer today has a Sub-D25 female connector which is called LPT1.

Pinning 36 pin Amphenol

Male	Female

Pin	Signal	Abbr.	Source
1	Data Strobe (low)	STROBE	Computer
2	Data Bit 1 (LSB)	D1	Computer
3	Data Bit 2	D2	Computer
4	Data Bit 3	D3	Computer
5	Data Bit 4	D4	Computer
6	Data Bit 5	D5	Computer
7	Data Bit 6	D6	Computer
8	Data Bit 7	D7	Computer
9	Data Bit 8 (LSB)	D8	Computer
10	Acknowledge (low)	ACK	Printer
11	Busy (high)	BUSY	Printer
12	Paper End (high)	PE	Printer
13	Select (high)	SEL	Printer
14	Supply Ground		-
15	Oscillator Transmit		Printer
16	Logical Ground		-
17	Chassis Ground		-
18	+5 Vdc	+V	Printer
19	Return Data Strobe		-
20	Return Data Bit 1		-
21	Return Data Bit 2		-
22	Return Data Bit 3		-
23	Return Data Bit 4		-
24	Return Data Bit 5		-
25	Return Data Bit 6		-
26	Return Data Bit 7		-
27	Return Data Bit 8		-
28	Return ACK		-
29	Return BUSY		-
30	Return Input Prime		-
31	Input Prime (low)		Computer
32	Fault (low)	FAULT	Printer
33	-	-	-
34	-	-	-
35	-	-	-
36	-	-	-

Pinning Sub-D25

Male	Female

Pin	Signal	Abbr.	Source
1	Data Strobe (low)	STROBE	Computer
2	Data Bit 1 (LSB)	D1	Computer
3	Data Bit 2	D2	Computer
4	Data Bit 3	D3	Computer
5	Data Bit 4	D4	Computer
6	Data Bit 5	D5	Computer
7	Data Bit 6	D6	Computer
8	Data Bit 7	D7	Computer
9	Data Bit 8 (LSB)	D8	Computer
10	Acknowledge (low)	ACK	Printer
11	Busy (high)	BUSY	Printer
12	Paper End (high)	PE	Printer
13	Select (high)	SEL	Printer
14	Auto Line Feed (low)	LF	Computer
15	Error (low)	ERROR	Printer
16	Initialize Printer (prime-low)	PRIME	Computer
17	Select Input (low)	SEL	Computer
18	Return/ground	GND	-
19	Return/ground	GND	-
20	Return/ground	GND	-
21	Return/ground	GND	-
22	Return/ground	GND	-
23	Return/ground	GND	-
24	Return/ground	GND	-
25	Return/ground	GND	-

Functional Description

STROBE: Active low pulse used to transfer data into the printer. Pulse with must be between 0.5 and 500 microseconds for most printers.

Dn: Data lines, high is a one.

ACK: Active low pulse indicates that data has been received and the printer is ready to accept more.

BUSY: A high signal indicates that the printer cannot receive data.

PE: A high signal indicates that the printer is out of paper (Paper End)

SELECT OUT: A high signal indicates that the printer is on-line

AUTO FEED: A low signal indicates to the printer that a line feed is required after each Carriage return. This signal is used as a ground line by some manufacturers.

OSCXT: A 100-200 KHz signal used by true Centronics printers only.

+5V: +5Vdc Not provided by all manufacturers

PRIME: A low signal resets the printer to its power-up state and the printer buffer is cleared

FAULT: A low signal indicates that the printer is in an off-line or error state

LINE COUNT: Used by true Centronics printers only. Most of the time not used

SELECT IN: A high signal indicates to the printer that a DC1/ DC3 code is valid. This signal is used by a few manufacturers

STROBE:	Active low pulse used to transfer data into the printer.	Pulse with must be between 0.5 and 500 microseconds for most printers.
Dn:	Data lines, high is a one.
ACK:	Active low pulse indicates that data has been received and the printer is ready to accept more.
BUSY:	A high signal indicates that the printer cannot receive data.
PE:	A high signal indicates that the printer is out of paper (Paper End)
SELECT OUT:	A high signal indicates that the printer is on-line
AUTO FEED:	A low signal indicates to the printer that a line feed is required after each Carriage return.	This signal is used as a ground line by some manufacturers.
OSCXT:	A 100-200 KHz signal used by true Centronics printers only.
+5V:	+5Vdc	Not provided by all manufacturers
PRIME:	A low signal resets the printer to its power-up state and the printer buffer is cleared
FAULT:	A low signal indicates that the printer is in an off-line or error state
LINE COUNT:	Used by true Centronics printers only.	Most of the time not used
SELECT IN:	A high signal indicates to the printer that a DC1/ DC3 code is valid.	This signal is used by a few manufacturers

Sub-D25 to Centronics cable
Sub-D25 Centronics 36
1 --- 1
2 --- 2
3 --- 3
4 --- 4
5 --- 5
6 --- 6
7 --- 7
8 --- 8
9 --- 9
10 --- 10
11 --- 11
12 --- 12
13 --- 13
14 --- 14
15 --- 32
16 --- 31
17 --- 36
18 --- 33
19 --- 19
20 --- 21
21 --- 23
22 --- 25
23 --- 27
24 --- 29
25 --- 30

Sub-D25		Centronics 36
1	---	1
2	---	2
3	---	3
4	---	4
5	---	5
6	---	6
7	---	7
8	---	8
9	---	9
10	---	10
11	---	11
12	---	12
13	---	13
14	---	14
15	---	32
16	---	31
17	---	36
18	---	33
19	---	19
20	---	21
21	---	23
22	---	25
23	---	27
24	---	29
25	---	30

Resources:

Sub-D25		Centronics 36
1	---	1
2	---	2
3	---	3
4	---	4
5	---	5
6	---	6
7	---	7
8	---	8
9	---	9
10	---	10
11	---	11
12	---	12
13	---	13
14	---	14
15	---	32
16	---	31
17	---	36
18	---	33
19	---	19
20	---	21
21	---	23
22	---	25
23	---	27
24	---	29
25	---	30

Sub-D25		Centronics 36
1	---	1
2	---	2
3	---	3
4	---	4
5	---	5
6	---	6
7	---	7
8	---	8
9	---	9
10	---	10
11	---	11
12	---	12
13	---	13
14	---	14
15	---	32
16	---	31
17	---	36
18	---	33
19	---	19
20	---	21
21	---	23
22	---	25
23	---	27
24	---	29
25	---	30

Sub-D25		Centronics 36
1	---	1
2	---	2
3	---	3
4	---	4
5	---	5
6	---	6
7	---	7
8	---	8
9	---	9
10	---	10
11	---	11
12	---	12
13	---	13
14	---	14
15	---	32
16	---	31
17	---	36
18	---	33
19	---	19
20	---	21
21	---	23
22	---	25
23	---	27
24	---	29
25	---	30