HP C1557A DDS 3 Autoloader

Specification

Performance

Environment

Jumpers & Switches

Specification

Apricot Part Number	PT15904631
Vendor	H.P.
Series	DDS 3 AL
Model	C1557A
Form Factor	5.25" HH
Height	3.2" / 82mm
Width	5.7" / 146mm
Length	8.0" / 203.2mm
Weight	4.8lbs / 2.2Kg
Tape Type	DDS-3 125m 4mm DAT
Tape Length	125m
Capacity Native	6x12GB=72GB
Capacity Compressed @2:1	6x24GB=144GB
Recording Media	MP++
Cartridge Size (W x D)	73 x 53mm
Flux Density	152,500 ftpi
Tracks	2,804 trks/inch

Performance

Transfer Rate, @ 2:1 Burst	2MB/s
Transfer Rate, Native Burst	1MB/s
Head to Tape Speed, Read / Write	236 ips
Search / Rewind	100x normal
Physical Interface	SE 8bit SCSI
Logical Interface	SCSI-2
Maximum Transfer Rate	5MB/s
Buffer Size	2MB
Hardware Compression	Yes, DCLZ
Recording Method	Helical Scan
Recording Code	DDS-DC
Error Recovery Type	Reed S'mon C3
Read after Write Verify	Yes
Correctable Read Error Rate	1 in 10⁴ bits
Uncorrectable Read Error Rate	1 in 10¹⁵ bits

Environment

Minimum Ambient operating Temperature	5°C
Maximum Ambient operating Temperature	45°C
Maximum Thermal Gradient	2°C/minute
Average Power Consumption	Combined
Operating Maximum	28W
Nominal Read / Write	9W
Nominal Idle	9W
DC Power Requirements	Combined
+12V Peak	2.0Amps
+12V Operational Nominal	0.2Amps
+5V Peek	1.20Amps
+5V Stepping Head Nominal	1.20Amps
MTBF	55,000 poh

Jumpers & Switches

SCSI ID

The SCSI ID is set using the jumpers on the set of pins beside the SCSI connector at the rear of the drive, shown below:

SCSI Jumper Pins

The three significant bits in the ID give a range of 0 to 7 as follows:

SCSI ID	Bit 2	Bit 1	Bit 0
0	0	0	0
1	0	0	1
2	0	1	0
3	0	1	1
4	1	0	0
5	1	0	1
6	1	1	0
7	1	1	1

1 = shorted
0 = open

The drive reads the SCSI ID at power-up and during self-test.

Data Compression Control

Data compression can be controlled through the jumper pin shown above. The pin is only monitored at power-on, and controls whether data compression is enabled by default. Any subsequent change to the pin are ignored.

Pin State	Effect
Unconnected	This is the default. Data compression is controlled by the configuration switches 1 and 2 (on the underside of the drive) and through the SCSI MODE SELECT command.
Connected to 0V	Data compression is disabled. The setting of configuration switch 1 is ignored. Switch 2 is valid. However, data compression can still be controlled through MODE SELECT. Note that when reading, the drive will always decompress compressed data It follows from this that if you wish to use this pin, you should switch 1 on the underside of the drive to ON

Terminator Power

The drive will provide termination power for the SCSI termination resistors if a jumper is set across the two pins marked "Term power" as shown in the diagram

Configuration switches

There is a set of configuration switches on the underside of the drive, shown below:

With the drive switched off, use the information below to select the correct configuration for your system.

Note
For the drive to operate correctly, appropriate drivers and application software must be loaded on the host computer.

Data Compression

Switches 1 and 2 are normally used to configure the way in which data compression is set for the drive. The following table shows the available options:

Switch 1	Switch 2	Meaning
On	On	Compression enabled at power-on with host control
On	Off	Compression enabled at power-on no host control
Off	On	Compression disabled at power-on. The host is allowed to control compression
Off	Off	Compression disabled at power-on no host control

When switch 1 is on, data written to the tape will be compressed without the knowledge of the host.

Media Recognition System (MRS)

Switch 3 is used to configure the drive to respond to DDS Media Recognition System tapes:

Switch 3	Meaning
On	The Media Recognition System is disabled. All DDS tapes are treated the same, whether they posses the Media Recognition stripes or not.
Off	The Media Recognition System is active. This is the default setting. Non Media Recognition System tapes are treated as if they are write-protected.

Switches 4 to 8

Switches 4 to 8 are used to specify connectivity and functionality according to host or customer requirements. The default settings for all switches is on.

Option switches

The autoloader option switches are on the rear-panel. The switches are read at power-on. When the autoloader is switched off, you can set the following configurations (other settings are not used at this time).

4	3	2	1	Value	Auto-stack	Auto-eject	Allow Resequencing	LUN 1 Magazine Ready	LUN 0 Drive Inquiry
On	Off	Off	On	1h	Enabled	Enabled
Off	On	On	On	6h (HP Series 800)			Enabled	Enabled	Enabled
Off	On	On	On	7h (HP Series 700)			Enabled	Enabled
On	On	On	On	Fh (Default)

Auto-stack	The autoloader will enter Stacker mode after a magazine has been inserted, and the first cartridge will automatically be loaded.
Auto-eject	When the autoloader is in Stacker mode it will eject the magazine after the last cartridge in the magazine is loaded.
Allow Resequencing	While the autoloader is in Stacker mode, you can select another cartridge to be loaded into the drive by using the Select and Load buttons. When this option is not enabled, the Load and Select buttons are ignored in Stacker mode.
LUN 1 Magazine Ready	A TEST UNIT READY command to LUN 1 will receive a NOT READY status message unless a magazine is present and magazine cencus data is available. When this option is not enabled, a TEST UNIT READY command will receive a GOOD status report whenever the autoloader has completed the power-on self-tests. This provides a method of detecting whether a magazine is present.
LUN 0 Drive Inquiry	The product ID sent in response to an INQUIRY command to LUN 1 will be that of the embedded tape drive. When this option is not enabled the ID sent is that of the entire autoloader.