DS21Q50L+ Maxim Integrated Products, DS21Q50L+ Datasheet - Page 45

• Manufacturer Part Number: DS21Q50L+
• Description: IC TXRX E1 QUAD 100-LQFP
• Manufacturer: Maxim Integrated Products

Specifications of DS21Q50L+

• Function: Transceiver
• Interface: E1
• Number Of Circuits: 4
• Voltage - Supply: 3.14 V ~ 3.47 V
• Current - Supply: 230mA
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Surface Mount
• Package / Case: *
• Includes: AIS Alarms Detector and Generator, Loopback Functions, PRBS Generator / Detector, Remote Detector and Generator
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Power (watts): -

8. PRBS GENERATION AND DETECTION
The DS21Q50 can transmit and receive the 2
T O.151 specifications. The PRBS pattern can be unframed (in all 256 bits of the frame), framed (in all
time slots except TS0), or in any single time slot. Register CCR5 contains the control bits for configuring
the transmit and receive PRBS functions.
and receive operation modes. In transmit and receive mode 1 operation, the transmit and receive channel-
monitor select bits of registers CCR3 and CCR4 have an alternate use. When these modes are selected,
those bits determine which time slots transmit and/or receive the PRBS pattern.
SR2.0 indicates when the receiver has synchronized to the PRBS pattern. The PRBS synchronizer
remains in sync until it experiences 6-bit errors or more within a 64-bit span. Choosing any receive mode
other than NORMAL causes the 16-bit E-bit error counter—EBCR1 and EBCR2—to be reconfigured for
counting PRBS errors.
User-definable outputs OUTA or OUTB can be configured to output a pulse for every bit error received.
See Section
rates during PRBS testing. Once synchronized, any bit errors received cause a positive-going pulse,
synchronous with RCLK.
Table 8-1. Transmit PRBS Mode Select
Table 8-2. Receive PRBS Mode Select
(CCR5.3)
(CCR5.1)
TPRBS1
RPRBS1
0
0
1
1
0
0
1
1
15
(CCR5.2)
(CCR5.0)
TPBRS0
RPBRS0
and
0
1
0
1
0
1
0
1
Table 15-1
Mode 0: Normal (PRBS disabled)
Mode 1: PRBS in TSx. PRBS pattern is transmitted in a single time slot
(TS). In this mode, the transmit channel-monitor select bits in register
CCR3 are used to select a time slot in which to transmit the PRBS
pattern.
Mode 2: PRBS in all but TS0. PRBS pattern is transmitted in time slots 1
through 31.
Mode 3: PRBS unframed. PRBS pattern is transmitted in all time slots.
Mode 0: Normal (PRBS disabled)
Mode 1: PRBS in TSx. PRBS pattern is received in a single time slot
(TS). In this mode, the receive channel-monitor select bits in register
CCR4 are used to select a time slot in which to receive the PRBS pattern.
Mode 2: PRBS in all but TS0. PRBS pattern is received in time slots 1
through 31.
Mode 3: PRBS unframed. PRBS pattern is received in all time slots.
for details. This signal can be used with external circuitry to track bit error
Table 8-1
15
- 1 PRBS pattern. This PRBS pattern complies with ITU-
45 of 87
and
Table 8-2
MODE
MODE
show the selection criteria for transmit
DS21Q50