Lucent Technologies Inc.
Lucent Technologies Inc.
193
Preliminary Data Sheet
October 2000
T7630 Dual T1/E1 5.0 V Short-Haul Terminator (Terminator-II)
FDL Parameter/Control Registers (800—80E; E00—E0E)
(continued)
Table 186. FDL Transmitter Configuration Control Register (FDL_PR3) (803; E03)
1. Do
not
set FTABT = 1 and FTFC = 1 at the same time.
Table 187. FDL Transmitter FIFO Register (FDL_PR4) (804; E04)
Table 188. FDL Transmitter Idle Character Register (FDL_PR5) (805; E05)
Bit
0—5
Symbol
FTIL0—FTIL5
FDL Transmitter Interrupt Level.
These bits specify the minimum number of empty
positions in the transmit FIFO which triggers a transmitter-empty (FTEM) interrupt.
Encoding is in binary; bit 0 is the least significant bit. A code of 001010 will generate an
interrupt when the transmit FIFO has ten or more empty locations. The code 000000
generates an interrupt when the transmit FIFO is empty. The number of empty transmit
FIFO locations is obtained by reading the transmit FDL status register FDL_SR1.
FTABT
FDL Transmitter Abort.
FTABT = 1 forces the transmit FDL unit to abort the frame at the
last user data byte waiting for transmission. When the transmitter reads the byte tagged
with FTABT, the abort sequence (01111111) is transmitted in its place. A full byte is guar-
anteed to be transmitted. Once set for a specific data byte, the internal FTABT status
cannot be cleared by writing to this bit. Clearing this bit has no effect on a previously writ-
ten FTABT. The last value written to FTABT is available for reading.
FTFC
FDL Transmitter Frame Complete.
FTFC = 1 forces the transmit FDL unit to terminate
the frame normally after the last user data byte is written to the transmit FIFO. The CRC
sequence and a closing flag are appended. FTFC should be set to 1 within 1 ms of writ-
ing the last byte of the frame in the transmit FIFO. When the transmit FIFO is empty, writ-
ing two data bytes to the FIFO before setting FTCF provides a minimum of 1 ms to write
FTFC = 1. Once set for a specific data byte, the internal FTFC status bit cannot be
cleared by writing to this bit. Clearing this bit has no effect on a previously written FTFC.
The last value written to FTFC is available for reading.
Description
6
1
7
1
Bit
0—7
Symbol
FTD0—FTD7
FDL Transmit Data.
The user data to be transmitted via the FDL block are loaded
through this register.
Description
Bit
0—7
Symbol
FTIC0—
FTIC7
Description
FDL Transmitter Idle Character.
This character is used only in transparent mode (regis-
ter FDL_PR9 bit 6 = 1). When the pattern match bit (register FDL_PR9 bit 5) is set to 1,
the FDL transmit unit sends this character whenever the transmit FIFO is empty. The
default is to send the ones idle character, but any character can be programmed by the
user.