Specifications

Data Structures
1.16 SCSI Connection Descriptor Table (SCDT)
Table 1–18 (Cont.) Contents of SCSI Connection Descriptor Table
Field Name Contents
SCDT$L_BADPHS_CNT* Count of bad phase errors.
SCDT$L_RETRY_CNT* Count of retries.
SCDT$L_RST_CNT* Count of bus resets.
SCDT$L_CTLERR_CNT* Count of controller errors.
SCDT$L_BUSERR_CNT* Count of bus errors.
SCDT$L_CMDSENT* Number of commands sent on this connection.
SCDT$L_MSGSENT* Number of messages sent on this connection.
SCDT$L_BYTSENT* Number of bytes sent during DATA OUT phase.
SCDT$L_CON_FLAGS* Connection-specific flags. The SCSI port driver sets or clears these flags
according to information the SCSI class driver supplies to the SPI$SET_
CONNECTION_CHAR macro. The following bits are defined:
SCDT$V_ENA_DISCON Enable disconnect
SCDT$V_DIS_RETRY Disable command retry
SCDT$V_TARGET_
MODE
Enable asynchronous event notification from
target
SCDT$L_SYNCHRONOUS* Synchronous data transfer enabled field. This longword contains
1 if synchronous data transfers are enabled for this connection;
otherwise it contains a 0. The SCSI port driver writes this field
according to information the SCSI class driver supplies to the SPI$SET_
CONNECTION_CHAR macro.
SCDT$W_REQACK_
OFFSET*
For synchronous data transfers, maximum number of REQs outstanding on
the connection before an ACK is transmitted. The SCSI port driver writes
this field according to information the SCSI class driver supplies to the
SPI$SET_CONNECTION_CHAR macro.
SCDT$W_TRANSFER_
PERIOD*
Number of 4-nanosecond ticks between a REQ and an ACK on this
connection. The SCSI port driver writes this field according to information
the SCSI class driver supplies to the SPI$SET_CONNECTION_CHAR
macro.
SCDT$W_BUSY_RETRY_
CNT*
Remaining number of retries allowed on this connection to successfully
send a command to the target device. The SCSI port driver initially writes
this field according to information the SCSI class driver supplies to the
SPI$SET_CONNECTION_CHAR macro.
SCDT$W_ARB_RETRY_
CNT*
Remaining number of retries allowed on this connection while waiting for
the port to win arbitration of the bus. The SCSI port driver initially writes
this field according to information the SCSI class driver supplies to the
SPI$SET_CONNECTION_CHAR macro.
SCDT$W_SEL_RETRY_
CNT*
Select retry count. Remaining number of retries allowed on this connection
while waiting for the port to be selected by the target device. The SCSI
port driver initially writes this field according to information the SCSI
class driver supplies to the SPI$SET_CONNECTION_CHAR macro.
SCDT$W_CMD_RETRY_
CNT*
Remaining number of retries allowed on this connection to successfully
send a command to the target device. The SCSI port driver initially writes
this field according to information the SCSI class driver supplies to the
SPI$SET_CONNECTION_CHAR macro.
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