Cirrus Logic CS61584A - Manual (Page 27)

CS61584A
DS261PP5 27
DS261PP5
Factory Test: Must be cleared for normal device
operation.
9.1.4 Control B Registers
The Control B registers are read-write registers and
are shown in Table 8. The Control B registers select
device configuration and loopback control.
TAOS: Controls the transmission of all ones to the
line interface. A TAOS request overrides the data
transmitted to the line interface during local and re-
mote loopbacks.
RLOOP: Controls the remote loopback function for
the channel.
LLOOP1: Controls the local loopback #1 function
for the channel. Includes the jitter attenuator, if en-
abled. In host mode, selecting LLOOP1 and
LLOOP2 simultaneously causes all ones to be out-
put from RPOS/RNEG (RDATA).
LLOOP2: Controls the local loopback #2 function
for the channel. Includes the line driver, line receiv-
er, and jitter attenuator, if enabled. See LLOOP1,
above, for receive all ones function.
CON[3:0]: Controls the configuration of the line
driver, line receiver, coder, and driver tristate as
shown in the Transmitter section. Both channels
must be configured to operate at the same rate (both
T1 or both E1).
9.1.5 Arbitrary Waveform Registers
In addition to the predefined T1 and E1 pulse
shapes, arbitrary pulse shapes may be created dur-
ing Host mode operation using the registers shown
in Table 9. This flexibility can be used to compen-
Control B Register (Channel 1)
Serial Port Address: 0x16; Parallel Port Address: 0xY6
Bit Description Definition Reset
Value 1 0
7 TAOS1 Enable transmit all ones Disable transmit all ones 0
6 RLOOP1 Enable remote loopback Disable remote loopback 0
5 LLOOP11 Enable local loopback #1 Disable local loopback #1 0
4 LLOOP21 Enable local loopback #2 Disable local loopback #2 0
3 CON31 Line configuration selections
(See Transmitter section)
1
2 CON21 1
1 CON11 1
0 CON01 0
Control B Register (Channel 2)
Serial Port Address: 0x17; Parallel Port Address: 0xY7
Bit Description Definition Reset
Value 1 0
7 TAOS2 Enable transmit all ones Disable transmit all ones 0
6 RLOOP2 Enable remote loopback Disable remote loopback 0
5 LLOOP12 Enable local loopback #1 Disable local loopback #1 0
4 LLOOP22 Enable local loopback #2 Disable local loopback #2 0
3 CON32 Line configuration selections
(See Transmitter section)
1
2 CON22 1
1 CON12 1
0 CON02 0
Table 8. Control B Registers
CS61584A
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