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Pin Assignments for I/O Connectors

Dell™ Latitude™ C840 Service Manual

USB Connector

Pin	Signal
1	VCC
2	-Data
3	+Data
4	Ground

Serial Connector

Pin	Signal	Pin	Signal
1	DCD	6	DSR
2	RXDA	7	RTS
3	TXDA	8	CTS
4	DTR	9	RI
5	GND

Parallel Connector

Pin	Signal	Pin	Signal
1	STRB#	11	BUSY
2	PD0	12	PE
3	PD1	13	SLCT
4	PD2	14	AFDF#
5	PD3	15	ERROR#
6	PD4	16	INIT#
7	PD5F	17	SLCT_IN
8	PD6F	18-23	GND
9	PD7F	24	DFDD/LPT#
10	ACK#	25	GND

Video Connector

Pin	Signal	Pin	Signal
1	RED	9	CRT_VCC
2	GREEN	10	GND
3	BLUE	11	MSEN#
4	NC	12	DAT_DDC2
5	GND	13	HSYNC
6	GND	14	VSYNC
7	GND	15	CLK_DDC2
8	GND

PS/2 Connector

Pin	Signal
1	DAT_KBD
2	DAT_SM1
3	GND
4	PS2VCC
5	CLK_KBD
6	CLK_SM1

S-Video TV-Out Connector

S-Video
Pin	Signal
1	GND
2	GND
3	DLUMA-L
4	DCRMA-L

Composite Video
Pin	Signal
5	SPDIF
6	DCMPS-L
7	SPGND

Docking Connector

Pin	Signal	Pin	Signal
1	STRB#/5V	101	VGA_GRN
2	PD0	102	GND
3	PD1	103	VGA_RED
4	PD2	104	GND
5	PD3	105	VGA_BLU
6	PD4	106	DOCK_SD/MODE
7	PD5	107	D_IRTX
8	PD6	108	D_IRRX
9	PD7	109	GND
10	GND	110	SPIRQB#
11	DOCK_SPKR	111	SPIRQC#
12	DOCK_MIC	112	DAT_DDC2
13	DOCK_LINE	113	CLK_DDC2
14	DOCK_CDROM	114	SPAR
15	GND	115	SPME#
16	M_SEN#	116	GND
17	POWER_SW#	117	SSERR#
18	QPCIEN#	118	SPERR#
19	S1.6M_EN#	119	SLOCK#
20	DFDD/LPT#	120	SSTOP#
21	GND	121	GND
22	NC	122	SDEVSEL#
23	NC	123	STRDY#
24	D_ATCTLED	124	SIRDY#
25	D_PWRLED	125	SFRAME#
26	DOCK_PWR_SRC	126	SCLKRUN#
27	DOCK_PWR_SRC	127	GND
28	DOCK_PWR_SRC	128	SGNTA#
29	GND	129	SREQA#
30	+5VDOCK	130	SGNT0#
31	+5VDOCK	131	SREQ0#
32	+5VDOCK	132	SPCIRST#
33	+5VDOCK	133	SH1SEL#
34	+5VDOCK	134	GND
35	GND	135	SWRPRT#
36	DOCK_PWR_SRC	136	SDSKCHG#/DRQ
37	DOCK_PWR_SRC	137	SDIR#
38	DOCK_PWR_SRC	138	STRK0#
39	DOCK_PWR_SRC	139	SSTEP#
40	GND	140	SDRV1#
41	DOCK_+DC_IN	141	GND
42	DOCK_+DC_IN	142	SMRT1#
43	DOCK_+DC_IN	143	SWRDATA#
44	DOCK_+DC_IN	144	SWGATE#
45	DOCK_+DC_IN	145	SRDATA#
46	DOCK_+DC_IN	146	SINDEX#
47	DOCK_+DC_IN	147	GND
48	DOCK_+DC_IN	148	NC
49	GND	149	+5VALW
50	LOW_PWR	150	NC
51	HSYNC	151	GND
52	VSYNC	152	CLK_SPCI
53	GND	153	GND
54	DOCKED	154	SAD0
55	USB_VD1+	155	SAD1
56	USB_VD1-	156	SAD2
57	GND	157	SAD3
58	USB_VD2+	158	SAD4
59	USB_VD2-	159	SAD5
60	DOCKOCI#	160	SAD6
61	RUN_ON#	161	GND
62	GND	162	SAD7
63	NC	163	SAD8
64	DOCK_SCLK	164	SC/BE0#
65	DOCK_LRCK	165	SAD9
66	DOCK_MCLK	166	SAD10
67	GND	167	SAD11
68	+12V	168	SAD12
69	AFD#	169	GND
70	ERROR#	170	SAD13
71	ACK#	171	SAD14
72	GND	172	SAD15
73	INIT#	173	SAD16
74	SLCT_IN#	174	SC/BE1#
75	BUSY	175	CD/BE2#
76	PE	176	GND
77	SLCT	177	SAD17
78	GND	178	SAD18
79	DAT_SMB	179	SAD19
80	DCLK_SMB	180	SAD20
81	SMB_INIT#	181	SAD21
82	GND	182	GND
83	DAT_DOCKSM1	183	SAD22
84	CLK_DOCKSM1	184	SAD23
85	DAT_DOCKKBD	185	SAD24
86	CLK_DOCKKBD	186	SC/BE3#
87	GND	187	SAD25
88	RI0	188	GND
89	CTS0	189	SAD26
90	RTS0	190	SAD27
91	DSR0	191	SAD28
92	GND	192	SAD29
93	DTR0	193	SAD30
94	TXD0#	194	SAD31
95	RXD0#	195	GND
96	DCD0	196	NC
97	NC	197	NC
98	+5VSUS	198	NC
99	NC	199	NC
100	NC	200	GND

IEEE 1394 Connector

Pin	Signal
1	TPB-
2	TPB+
3	TPA-
4	TPA+

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