PM4341AT1XC
DATA SHEET
PMC-900602
ISSUE 7
T1 FRAMER/TRANSCEIVER
Register 35H: XFDL Interrupt Status
Bit
Type
Function
Default
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Unused
Unused
Unused
Unused
Unused
Unused
INT
X
X
X
X
X
X
1
R
R/W
UDR
0
INT:
The INT bit indicates when the XFDL is ready to accept a new data byte for
transmission.The INT bit is set to a logic 1 when the previous byte in the
Transmit Data register has been loaded into the parallel to serial converter
and a new byte can be written into the Transmit Data register.The INT bit is
set to a logic 0 while new data is in the Transmit Data register.The INT bit is
not disabled by the INTE bit in the configuration register. The INT bit is set to
logic 1 when the T1XC is reset.
UDR:
The UDR bit indicates when the XFDL has underrun the data in the Transmit
Data register.The UDR bit is set to a logic 1 if the parallel to serial conversion
of the last byte in the Transmit Data register has completed before the new
byte was written into the Transmit Data register. Once an underrun has
occurred, the XFDL transmits an ABORT, followed by a flag, and waits to
transmit the next valid data byte. If the UDR bit is still set after the
transmission of the flag the XFDL will continuously transmit the all-ones idle
pattern. The UDR bit can only be cleared by writing a logic 0 to the UDR bit
position in this register.
PROPRIETARY AND CONFIDENTIAL TO PMC-SIERRA, INC., AND FOR ITS CUSTOMERS’ INTERNAL USE
139
PMC [ PMC-SIERRA, INC ]
