T1/E1 Short Haul Transceiver with Crystal-less Jitter Attenuation — LXT350
.
Table 5. Control and Operational Mode Selection
Input to Pin1
Mode of Operation
B8ZS/HDB3
Encoder/Decoder
Mode TRSTE Hardware Host2 Unipolar Bipolar AMI Enc/Dec
All Outputs Tristated
Low
Low
Low
High
Open
Low
On
On
On
Off
Off
Off
On
On
On
Off
Off
Off
On
On
On
Off
Off
Off
Off
Off
On
x
On
On
Off
x
Off3
Off3
On
x
Off
Off
Off
x
No
Yes
No
Low
High
High
High
Open
Open
Open
No
High
Open
Low
x
x
x
x
Yes
No
x
x
x
x
On
On
On
Off
Off
Off
Off
Off
Off
On
On
On
No
High
Open
Yes
No
1. Open is either a midrange voltage or the pin is floating.
2. In Host mode, the contents of register CR1 determine the operation mode.
3. Encoding is done externally.
2.7
Diagnostic Mode Operation
The LXT350 offers multiple diagnostic modes as listed in Table 6. Note that various diagnostic
modes are only available in Host mode. In Hardware mode, the diagnostic modes are selected by a
combination of pin settings. In Host mode, the diagnostic modes are selected by writing
appropriate register bits. The following paragraphs provide details of the diagnostic modes.
Table 6. Diagnostic Mode Availability
Availability1
Host Mode
Maskable2
Diagnostic Mode
Hardware
Host
Loopback Modes
Local Loopback (LLOOP)
Analog Loopback (ALOOP)
Remote Loopback (RLOOP)
Dual Loopback (DLOOP)
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
No
No
No
No
Internal Data Pattern Generation
Error Insertion and Detection
Transmit All Ones (TAOS)
Yes
Yes
Yes
Yes
No
Quasi-Random Signal Source (QRSS)
Yes
Bipolar Violation Insertion (INSBPV)
Logic Error Insertion (INSLER)
Yes
Yes
Yes
Yes
No
No
1. In Hardware mode, a combination of pin settings selects the Diagnostics Modes. In Host mode, writing appropriate bits in the
Control Registers selects the Diagnostic Modes.
2. Host mode allows interrupt masking by writing a “1” to the corresponding bit in the Interrupt Clear Register.
Datasheet
19
ETC [ ETC ]
