Cabling and Configuring SCSI Devices: Dell PowerEdge Expandable RAID Controller
Cabling and Configuring SCSI Devices: Dell� PowerEdge�
Expandable RAID Controller
Connecting SCSI Devices | Terminating the SCSI Devices | Terminator Power (TermPWR) | Target
IDs | SCSI Connectors | 68-Pin High-Density SCSI Connector | Cabling Options for the 68-Pin Connector
| 68-Pin SCSI Connector Pinout | 50-Pin Low-Density Connectors
When connecting SCSI devices:
- Disable termination on any SCSI device that does not sit at the
end of the SCSI bus.
- Configure all SCSI devices to supply TermPWR.
- Set proper target IDs (TIDs) for all SCSI devices.
- Distribute SCSI devices evenly across the SCSI channels for optimum
performance.
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NOTE: The cable length should not exceed 3 meters for
Fast SCSI (10 MB) devices. The cable length should not exceed 6 meters for non-Fast SCSI
devices.
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- Try to connect all non-disk SCSI devices to a SCSI channel that has no
SCSI disk drives connected to it.
You must terminate the SCSI bus properly. Termination should be set at
each end of the SCSI cable. If the RAID controller is at one end of the cable for a
channel, it sets termination automatically at that end. Otherwise, the controller disables
its own termination and you must set
termination at the cable ends. In a disk array, SCSI bus termination must be configured so
that removing a SCSI device does not disturb the termination.
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NOTE: All RAID controller SCSI channels need TermPWR
to operate. If a channel is not being used and no auxiliary power source is connected,
change the jumper setting for that channel to supply TermPWR from the PCI bus. |
Jumpers J20 and J17 control TermPWR for the RAID controller SCSI channels. The factory settings for
these jumpers supply TermPWR from the PCI bus.
Connector J3
provides auxiliary terminator power (TermPWR) source for SCSI channels. J3 accepts a 4-pin
Molex plug typically used for diskette drives. Use auxiliary TermPWR if you have wide
termination on 2 SCSI channels with at least 1 channel having wide termination. Use this
connector only when J17 and/or J20 are configured for auxiliary-source SCSI TermPWR.
Each device in a specific SCSI channel must have a unique target
identifier (TID) in that channel. Non-disk devices (CD-ROM or tape drives) should have
unique SCSI IDs regardless of the channel where they are connected. See the documentation
for each SCSI device to set the TIDs.
The RAID controller automatically occupies TID 7 in each SCSI channel.
8-bit SCSI devices can only use the TIDs from 0 to 6. 16-bit devices can use the TIDs from
0 to 15.
The arbitration priority for a SCSI device depends on its TID, as
follows:
The RAID controller provides 3 types of SCSI connectors:
- Internal, high-density, 68-pin connectors for wide SCSI. Connector J4 is
for channel 0 and J5 is for channel 1.
- External, high-density, 68-pin connectors for wide SCSI. Connector J27 is
for channel 0 and J26 is for channel 1.
- Internal, low-density, 50-pin SCSI connectors. Connector J8 is for
channel 0 and J11 is for channel 1.
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NOTE: Do not use more than 2 types of connectors for
each SCSI channel. |
Each SCSI channel has a 68-pin, high-density, 0.050-inch pitch,
unshielded connector for connection to a wide SCSI device.
The following figures show the available options for cabling 68-pin SCSI
devices.
Connecting Internal Wide SCSI Devices
Connecting Internal and External Wide SCSI Devices
Converting From Internal Wide SCSI Connectors to Internal Non-Wide
Connectors (Type 2)
Converting From Internal Wide to Internal Non-Wide SCSI Connectors
(Type 30)
Converting From Internal Wide to Internal Non-Wide SCSI Connectors
(Type 3)
The connector pinouts are those specified for a single-ended primary bus
(P-CABLE). A hyphen before a signal name indicates that the signal is active low.
| Connector Pin |
Cable Pin |
Signal |
| 1 |
1 |
GRND |
| 2 |
3 |
GRND |
| 3 |
5 |
GRND |
| 4 |
7 |
GRND |
| 5 |
9 |
GRND |
| 6 |
11 |
GRND |
| 7 |
13 |
GRND |
| 8 |
15 |
GRND |
| 9 |
17 |
GRND |
| 10 |
19 |
GRND |
| 11 |
21 |
GRND |
| 12 |
23 |
GRND |
| 13 |
25 |
GRND |
| 14 |
27 |
GRND |
| 15 |
29 |
GRND |
| 16 |
31 |
GRND |
| 17 |
33 |
TERMPWR |
| 18 |
35 |
TERMPWR |
| 19 |
37 |
RESERVED1 |
| 20 |
39 |
GRND |
| 21 |
41 |
GRND |
| 22 |
43 |
GRND |
| 23 |
45 |
GRND |
| 24 |
47 |
GRND |
| 25 |
49 |
GRND |
| 26 |
51 |
GRND |
| 27 |
53 |
GRND |
| 28 |
55 |
GRND |
| 29 |
57 |
GRND |
| 30 |
59 |
GRND |
| 31 |
61 |
GRND |
| 32 |
63 |
GRND |
| 33 |
65 |
GRND |
| 34 |
67 |
GRND |
| 352 |
2 |
-DB(12) |
| 362 |
4 |
-DB(13) |
| 372 |
6 |
-DB(14) |
| 382 |
8 |
-DB(15) |
| 392 |
10 |
-DB(P1) |
| 40 |
12 |
-DB(0) |
| 41 |
14 |
-DB(1) |
| 42 |
16 |
-DB(2) |
| 43 |
18 |
-DB(3) |
| 44 |
20 |
-DB(4) |
| 45 |
22 |
-DB(5) |
| 46 |
24 |
-DB(6) |
| 47 |
26 |
-DB(7) |
| 48 |
28 |
-DB(P) |
| 49 |
30 |
GRND |
| 50 |
32 |
GRND |
| 51 |
34 |
TERMPWR |
| 52 |
36 |
TERMPWR |
| 53 |
38 |
RESERVED1 |
| 54 |
40 |
GRND |
| 55 |
42 |
-ATN |
| 56 |
44 |
GRND |
| 57 |
46 |
-BSY |
| 58 |
48 |
-ACK |
| 59 |
50 |
-RST |
| 60 |
52 |
-MSG |
| 61 |
54 |
-SEL |
| 62 |
56 |
-C/D |
| 63 |
58 |
-REQ |
| 64 |
60 |
-I/O |
| 652 |
62 |
-DB(8) |
| 662 |
64 |
-DB(9) |
| 672 |
66 |
-DB(10) |
| 682 |
68 |
-DB(11) |
1 Lines labeled "RESERVED" should be connected
to GRND in the bus terminator assemblies or in the end devices on the SCSI cable and
should be open in all other SCSI devices.
2 Leave this pin open if you are connecting to an 8-bit device.
Each channel has a 50-pin, low-density, 0.100-inch pitch, shrouded
connector for connection to a non-wide SCSI device. Cables for this 50-pin, low-density
connector are standard items provided by most cable manufacturers.
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