Intel® Server Platform SR6850HW4 TPS

SCSI Backplane Board

 

 

 

 

 

Signal

Type

Driver

 

Name and Description

LVD_IO_[P, N]

I/O

LVD hs

SCSI bus I/O phase. Driven by the target, these pins control the

 

 

 

direction of data transfer on the SCSI bus. When asserted, this signal

 

 

 

indicates input to the initiator. When not asserted, this signal indicates

 

 

 

output from the initiator.

 

 

 

 

 

GND

I/O

PWR

Ground. Provide secondary ground reference.

 

 

 

 

 

7.3.5 SCA2 80-pin Drive Connectors

The SCA2 connector carries power and signal between the SCSI Backplane Boardboard and hot-swap SCSI hard disk drives. The LVD SCSI bus signals are driven by either the Server Board Set SE8500HW4 Mainboard SCSI controller, the LVD transceiver, or the hot-swap SCSI hard disk drives. Table 47 provides a description of each signal on the SCSI connectors.

Table 47. .LVD SCSI Bus Signals

Signal

Type

Driver

Name and Description

LVD_DB[15..0]_[P, N]

I/O

LVD hs

SCSI data bus. Along with the DBP[1/0][P/N] pins they form the bi-

 

 

 

directional SCSI data bus.

 

 

 

 

LVD_DBP_[P, N]

I/O

LVD hs

SCSI data parity. Support parity on the SCSI bus.

LVD_DBP1_[P, N]

 

 

DBP[P/N] supports parity for data [7..0]

 

 

 

DBP1[P/N] supports parity for data [15..8]

 

 

 

 

DIFFSENSE

I

Analog

Differential sense. Monitor the DIFFSENSE signal from the

 

 

 

terminator. The voltage level determines the operating mode of the

 

 

 

target devices on the SCSI bus. If the voltage on the DIFFSENSE

 

 

 

signal is from –0.35V to +0.5V the mode will be SE. If it is from

 

 

 

+0.7V to 1.9V the mode will be LVD.

 

 

 

 

LVD_ATN_[P, N]

I/O

LVD hs

SCSI bus attention. Asserted by a SCSI device in initiator mode to

 

 

 

alert the target that the initiator has a message to transfer.

LVD_BSY_[P, N]

I/O

LVD hs

SCSI bus busy. In SE mode, these pins are bi-directional and are

 

 

 

asserted to gain use of the SCSI bus and to indicate that that SCSI

 

 

 

bus is in use.

 

 

 

 

LVD_ACK_[P, N]

I/O

LVD hs

SCSI bus acknowledge. Asserted by a SCSI device in initiator mode

 

 

 

to acknowledge the target’s request for a data transfer.

 

 

 

 

LVD_RST_[P, N]

I/O

LVD hs

SCSI bus reset. In SE mode, these pins are bi-directional and are

 

 

 

asserted when all the SCSI devices attached to the SCSI bus need

 

 

 

to be reset.

 

 

 

 

LVD_MSG_[P, N]

I/O

LVD hs

SCSI bus message phase. Asserted by a SCSI device in target

 

 

 

mode to indicate the Message In or Message Out phase.

LVD_SEL_[P, N]

I/O

LVD hs

SCSI bus select. In SE mode, these pins are bi-directional and are

 

 

 

asserted by the controller when attempting to select or reselect a

 

 

 

SCSI device.

 

 

 

 

LVD_CD_[P, N]

I/O

LVD hs

SCSI bus control/data phase. Asserted or de-asserted by a SCSI

 

 

 

device in target mode to indicate that control or data information is

 

 

 

being transferred over the SCSI bus

 

 

 

 

LVD_REQ_[P, N]

I/O

LVD hs

SCSI bus request. Asserted by a SCSI device in target mode to

 

 

 

indicate that the target is requesting a data transfer over the SCSI

 

 

 

bus.

 

 

 

 

LVD_IO_[P, N]

I/O

LVD hs

SCSI bus I/O phase. Asserted by a SCSI device in target mode to

 

 

 

indicate the direction of data movement on the SCSI bus between

 

 

 

the target and the initiator.

 

 

 

 

Revision 1.0

81

 

Intel order number D23151-001