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STP2002QFP
Sun Microelectronics
Fast Ethernet, Parallel Port, SCSI (FEPS) - STP2002QFP
5.3 Error Conditions and Recovery
There are two types of error conditions that can be encountered during the
normal operation of the Ethernet channel: fatal errors and non-fatal errors. Fa-
tal errors are errors that should never occur. They usually indicate a serious
failure of the hardware or a serious programming error. When this type of er-
ror occurs, the recovery process is non-graceful. The corresponding DMA
channel will freeze, and the software is expected to reset the channel after the
appropriate actions are taken to correct the failure. Fatal error events are al-
ways reported to the software via an interrupt. Non-fatal errors are errors that
are expected to occur when certain conditions occur on the network or in the
system. When this type of error occurs, a graceful recovery mechanism is pro-
vided via a combination of hardware and software, as described below. Non-
fatal errors may or may not be reported to the software.

5.3.1 Fatal Errors

The error conditions described below can occur both in the transmit and in the
receive DMA channels.
Master_Error_Ack
This error condition indicates that anSB_ERR_ACK was detected by the
DMA channel during a DVMA cycle.
Slave_Error_Ack
This error condition indicates that anSB_ERR_ACK was generated by the
DMA channel during a programmed I/O cycle. The hardware will generate
anSB_ERR_ACK if a programmed I/O cycle is executed with SB_SIZE oth-
er than a word transfer.
Late_Error
This error condition indicates that anSB_LATE_ERROR was detected by the
DMA channel during a DVMA cycle.
DMA_Read_Parity_Error
This error condition indicates that a parity error was detected by the DMA
channel during a DVMA read cycle.
Slave_Write_Parity_Error
This error condition indicates that a parity error was detected by the DMA
channel during a