
59
STP2002QFP
Fast Ethernet, Parallel Port, SCSI (FEPS) - STP2002QFP
Sun Microsystems,
The RESET state of this register is as follows:
P_ERR_PEND = 0 P_INT_EN = 0
P_INVALIDATE = 0 P_SLAVE_ERR = 0
P_RESET = 0 P_EN_DMA = 0
P_EN_CNT = 0 P_TC = 0
P_BURST_SIZE = 0 P_TCI_DIS = 0
P_EN_NEXT = 0 P_DMA_ON = 0
P_A_LOADED = 0 P_NA_LOADED = 0
P_WRITE = 1
P_INT_PEND:
Interrupt pending is the logical OR of the following enabled PP interrupt
sources:
(P_TC and !P_TCI_DIS), DS_IRQ, ACK_IRQ, BUSY_IRQ, ERR_IRQ,
PE_IRQ, SLCT_IRQ.
P_ERR_PEND:
Error pending will be set due to an SBus error acknowledge or an SBus late
error. It indicates an SBus error condition. PP DMA is stopped
(P_DMA_ON=0) when this bit is set. This bit can be reset by setting
P_INVALIDATE or P_RESET.
P_DRAINING:
When P_FIFO is draining to memory, both bits are set. Do not assert
P_RESET or P_INVALIDATE or write to the P_ADDR register when set.
P_TCI_DIS 23 When set, disables P_TC from generating an interrupt. R/W
P_EN_NEXT 24 When set, enables DMA chaining and next address/bytecount auto-load
mechanism. P_EN_CNT must also be set.
R/W
P_DMA_ON 25 DMA On. When set, indicates that DMA transfers are not disabled due to any
hardware or software condition.
R
P_A_LOADED 26 Set when the contents of the address and byte count are considered valid dur-
ing chained transfers.
R
P_NA_LOADED 27 Set when next address and byte count registers have beenwritten but have not
been used for chaining.
R
REV_MAJ [3:0] 31:28 FEPS major revision number R
Table 19: Control/Status Register Deļ¬nition
Field Bits Description Type