Bits used for parity control and generation, Table 2.2 – Avago Technologies LSI8751D User Manual

Page 37

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PCI Cache Mode

2-13

slave write operations causes a fatal DMA interrupt; SCRIPTS stops
running. Mask this interrupt with the EBPE Interrupt Enable bit, bit 1 in
the

DMA Interrupt Enable (DIEN)

register. These additional parity pins in

no way affect the generation or checking of the PCI specified parity line.

Table 2.2

Bits Used for Parity Control and Generation

BIt Name

Location

Description

Assert SATN/ on Parity
Errors

SCSI Control
Zero (SCNTL0)

,

Bit 1

When this bit is set, the LSI53C875 automatically
asserts the SATN/ signal upon detection of a parity
error. SATN/ is only asserted in initiator mode.

Enable Parity Checking

SCSI Control
Zero (SCNTL0)

,

Bit 3

Enables the LSI53C875 to check for parity errors. The
LSI53C875 checks for odd parity. This bit also checks
for parity errors on the four additional parity pins on the
LSI53C875N.

Assert Even SCSI Parity

SCSI Control
One (SCNTL1)

,

Bit 2

Determines the SCSI parity sense generated by the
LSI53C875 to the SCSI bus.

Disable Halt on SATN/
or a Parity Error (Target
Mode Only)

SCSI Control
One (SCNTL1)

,

Bit 5

Causes the LSI53C875 not to halt operations when a
parity error is detected in target mode.

Enable Parity Error
Interrupt

SCSI Interrupt
Enable Zero
(SIEN0)

, Bit 0

Determines whether the LSI53C875 generates an
interrupt when it detects a SCSI parity error.

Parity Error

SCSI Interrupt
Status Zero
(SIST0)

, Bit 0

This status bit is set whenever the LSI53C875 has
detected a parity error on the SCSI bus.

Status of SCSI Parity
Signal

SCSI Status Zero
(SSTAT0)

, Bit 0

This status bit represents the active HIGH current state
of the SCSI SDP0 parity signal.

SCSI SDP1 Signal

SCSI Status Two
(SSTAT2)

, Bit 0

This bit represents the active HIGH current state of the
SCSI SDP1 parity signal.

Latched SCSI Parity

SCSI Status Two
(SSTAT2)

, Bit 3

and

SCSI Status

One (SSTAT1)

,

Bit 3

These bits reflect the SCSI odd parity signal
corresponding to the data latched into the

SCSI Input

Data Latch (SIDL)

register.

Master Parity Error
Enable

Chip Test Four
(CTEST4)

, Bit 3

Enables parity checking during master data phases.

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