
133
STP2002QFP
Fast Ethernet, Parallel Port, SCSI (FEPS) - STP2002QFP
Sun Microsystems,
7.5.73 MIF Frame/Output RegisterThis 32-bit register serves as an “instruction register” when the MIF is pro-
grammed in the frame mode. In order to execute a read/write operation
from/to a transceiver register, the software has to load this register with a val-
id instruction, as per the IEEE 802.3u MII specification. After issuing an in-
struction, the software has to poll this register to check for instruction
execution completion. During a read operation, this register will also contain
the 16-bit data that was returned by the transceiver.
Table 224: MIF Bit-Bang Output Enable Address
Register Physical Address Access Size
MIF bit-bang output enable 0x8C0_7008 4 bytes
Table 225: MIF Frame/Output Register Address
Register Physical Address Access Size
MIF frame/output register 0x8C0_700C 4 bytes
Table 226: MIF Frame/Output Register Definition
Field Bits Description Type
DATA 15:0 Instruction payload. When issuing an instruction, this
field should be loaded with the 16-bit data to be written
into a transceiver register for a write, and is a don’t care
for a read. When polling for completion, this field is a
don’t care for a write, and contains the 16-bit data
returned by the transceiver for a read (if the valid bit is
set).
R/W
TA_LSB 16 Turn around, least significant bit. When issuing an
instruction, this bit should always be loaded with a 0.
When polling for completion, this bit serves as a valid
bit. When this bit is set to 1, the instruction execution
has been completed.
R/W
TA_MSB 17 Turn around, most significant bit. When issuing an
instruction, this bit should always be loaded with a 1.
When polling for completion, this bit is always a don’t
care.
R/W