Ethernet 10Base-T, 100Base-TX

Ethernet 10Base-T, 100Base-TX
RJ-45	Pin Color Signal Straight to Crossover to 1 White/Orange     TX+ 1 3 2 Orange   TX- 2 6 3 White/Green     RX+ 3 1 4 Blue   unused unused unused 5 White/Blue     unused unused unused 6 Green   RX- 6 2 7 White/Brown     unused unused unused 8 Brown   unused unused unused As per EIA-586B Standard

Serial ports

Serial ports

DB-9 (male) DB-25 (male)

Pin on DB-25 Pin on DB-9 Signal Function Details Sense (on PC) 2 3 TD Transmit Data Serial data output (TXD) Out 3 2 RD Receive Data Serial data input (RXD) In 4 7 RTS Request To Send PC informs modem that it is ready to exchange data Out 5 8 CTS Clear To Send Modem informs PC that it is ready to exchange data In 6 6 DSR Data Set Ready Modem informs PC that it is ready to establish link In 7 5 SG Signal Ground Ground reference - 8 1 CD Carrier Detect Modem informs PC that it has established link with other modem In 20 4 DTR Data Terminal Ready PC tells modem that it is ready to establish link Out 22 9 RI Ring Indicator Modem informs PC that the phone line is ringing In

Null modem cables

Null modem cables
PC DB-25 Male Connection Remote DB-25 Signal Function Sense Pin Pin Signal Function Sense TD Transmit Data Out 2 3 RD Receive Data In RD Receive Data In 3 2 TD Transmit Data Out SG Signal ground - 7 7 SG Signal ground - CTS Clear To Send In 5 4 RTS Request To Send Out RTS Request To Send Out 4 5 CTS Clear To Send In DSR Data Set Ready In 6 20 DTR Data Terminal Ready Out DTR Data Terminal Ready Out 20 6 DSR Data Set Ready In
PC DB-9 Male Connection Remote DB-25 Signal Function Sense Pin Pin Signal Function Sense RD Receive Data In 2 2 TD Transmit Data Out RD Receive Data In 3 3 TD Transmit Data Out SG Signal ground - 5 7 SG Signal ground - CTS Clear To Send In 8 4 RTS Request To Send Out RTS Request To Send Out 7 5 CTS Clear To Send In DSR Data Set Ready In 6 20 DTR Data Terminal Ready Out DTR Data Terminal Ready Out 4 6 DSR Data Set Ready In
PC DB-9 Male Connection Remote DB-9 Signal Function Sense Pin Pin Signal Function Sense RD Receive Data In 2 3 TD Transmit Data Out RD Receive Data In 3 2 TD Transmit Data Out SG Signal ground - 5 5 SG Signal ground - CTS Clear To Send In 8 7 RTS Request To Send Out RTS Request To Send Out 7 8 CTS Clear To Send In DSR Data Set Ready In 6 4 DTR Data Terminal Ready Out DTR Data Terminal Ready Out 4 6 DSR Data Set Ready In

Note: Linux uses RTS/CTS flow control.

Graphics for sockets and plugs

DB (Canon subminiature)
MINI DIN
RJ

Resistor color codes

Color		4 band codes				5 band codes
		1st band (digit)	2nd band (digit)	3rd band (multiplier)	4th band (tolerance)	1st band (digit)	2nd band (digit)	3rd band (digit)	4th band (multiplier)	5th band (tolerance)
Black		0	0			0	0	0
Brown		1	1	0		1	1	1	0	1 %
Red		2	2	00		2	2	2	00	2 %
Orange		3	2	000		3	3	3	000
Yellow		4	4	0 000		4	4	4	0 000
Green		5	5	00 000		5	5	5	00 000
Blue		6	6	000 000		6	6	6	000 000
Magenta		7	7			7	7	7
Gray		8	8			8	8	8
White		9	9			9	9	9
Gold				x 0.1	5 %				x 0.1
Silver				x 0.01	10 %				x 0.01

Transistor and FET pinout

Series resistor table for LEDs

LED color	If nominal	Supply voltage
		5 V	12 V	15 V	24 V
Red	10 mA	270 Ω 1/8 W	1 kΩ 1/8 W	1.2 kΩ 1/4 W	2.2 kΩ 1/4 W
Green Yellow Amber	20 mA	120 Ω 1/8 W	470 Ω 1/4 W	560 Ω 1/2 W	1 kΩ 1/2 W

Selected IC pinouts

DXF file

74x138 Decoder/Multiplexer
	On G2A and G2B low, G1 high, output selected by A,B and C goes low
	Maximum ratings for LS family Max HIGH level output current -0.4 mA Max LOW level output current 8 mA Max HIGH level input current 20 µA Max LOW level input current -0.36 mA
	Datasheet (external link)
74x154 4-Line to 16-Line Decoder/Demultiplexer
	On G1 and G2 low, output selected by A,B, C and D goes low
	Maximum ratings for LS family Max HIGH level output current -0.4 mA Max LOW level output current 8 mA Max HIGH level input current 20 µA Max LOW level input current -0.4 mA
	Datasheet (external link)
74x373 3-STATE Octal D-Type Transparent Latches
	On G high, outputs follow inputs On G low, outputs retains previous state With OE low, outputs are driven With OE high, outputs are in high impedance
	Maximum ratings for LS family Max HIGH level output current -2.6 mA Max LOW level output current 24 mA Max HIGH level input current 20 µA Max LOW level input current -0.4 mA
	Datasheet (external link)
74x374 3-STATE Octal Edge-triggered D-type Flip-Flop
	CLOCK rising edge copies inputs to outputs With OE low, outputs are driven With OE high, outputs are in high impedance
	Maximum ratings for LS family Max HIGH level output current -2.6 mA Max LOW level output current 24 mA Max HIGH level input current 20 µA Max LOW level input current -0.4 mA
	Datasheet (external link)
74x573 3-STATE Octal D-Type Transparent Latches (PCB friendly pinout)
	On G high, outputs follow inputs On G low, outputs retains previous state With OE low, outputs are driven With OE high, outputs are in high impedance
	Maximum ratings for LS family Max HIGH level output current -2.6 mA Max LOW level output current 24 mA Max HIGH level input current 20 µA Max LOW level input current -0.4 mA
	Datasheet (external link)
74x574 3-STATE Octal Edge-triggered D-type Flip-Flop (PCB friendly pinout)
	CLOCK rising edge copies inputs to outputs With OE low, outputs are driven With OE high, outputs are in high impedance
	Maximum ratings for LS family Max HIGH level output current -2.6 mA Max LOW level output current 24 mA Max HIGH level input current 20 µA Max LOW level input current -0.4 mA
	Datasheet (external link)