DS21Q42T Maxim Integrated Products, DS21Q42T Datasheet - Page 77

• Manufacturer Part Number: DS21Q42T
• Description: IC FRAMER ENHANCED T1 4X 128TQFP
• Manufacturer: Maxim Integrated Products

Specifications of DS21Q42T

• Controller Type: T1 Framer
• Interface: Parallel/Serial
• Voltage - Supply: 2.97 V ~ 3.63 V
• Current - Supply: 75mA
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Surface Mount
• Package / Case: 128-TQFP, 128-VQFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

For all bus configurations, one framer will be configured as the master device and the remaining framers
on the shared bus will be configured as slave devices. Refer to the IBO register description below for
more detail. In the 4.096 MHz bus configuration there is one master and one slave per bus. Figure 18-1
shows the DS21Q42 configured to support two 4.096 MHz buses. Bus 1 consists of framers 0 and 1. Bus
2 consists of framers 2 and 3. Framers 0 and 2 are programmed as master devices. Framers 1 and 3 are
programmed as slave devices. In the 8.192 MHz bus configuration there is one master and three slaves.
Figure 18-2 shows the DS21Q42 configured to support a 8.192 MHz bus. Framers 0 is programmed as
the master device. Framers 1, 2 and 3 are programmed as slave devices. Consult timing diagrams in
section 20 for additional information.
When using the frame interleave mode, all framers that share an interleaved bus must have receive signals
(RPOS & RNEG) that are synchronous with each other. The received signals must originate from the
same clock reference. This restriction does not apply in the byte interleave mode.
IBO: INTERLEAVE BUS OPERATION REGISTER (Address = 94 Hex)
Table 18-1. MASTER DEVICE BUS SELECT
(MSB)
MSEL1
SYMBOL
INTSEL
-
MSEL0
MSEL1
IBOEN
0
0
1
1
-
-
-
-
-
MSEL0
0
1
0
1
POSITION
IBO.6
IBO.6
IBO.5
IBO.4
IBO.3
IBO.2
IBO.1
IBO.0
-
Slave device
Master device with one slave device (4.096MHz bus rate)
Master device with three slave devices (8.192MHz bus rate)
Reserved
NAME AND DESCRIPTION
Not Assigned. Should be set to 0.
Not Assigned. Should be set to 0.
Not Assigned. Should be set to 0.
Not Assigned. Should be set to 0.
Interleave Bus Operation Enable
0 = Interleave Bus Operation disabled.
1 = Interleave Bus Operation enabled.
Interleave Type Select
0 = Byte interleave.
1 = Frame interleave.
Master Device Bus Select Bit 0 See table 18-1.
Master Device Bus Select Bit 1 See table 18-1.
-
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IBOEN
FUNCTION
INTSEL
MSEL0
MSEL1
(LSB)