DS31256 Maxim Integrated Products, DS31256 Datasheet - Page 62

• Manufacturer Part Number: DS31256
• Description: IC CTRLR HDLC 256-CHANNEL 256BGA
• Manufacturer: Maxim Integrated Products

Specifications of DS31256

• Controller Type: HDLC Controller
• Interface: Serial
• Voltage - Supply: 3 V ~ 3.6 V
• Current - Supply: 500mA
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Surface Mount
• Package / Case: 256-BGA
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

Bit #
Name
Default
Bit #
Name
Default
Register Name:
Register Description:
Register Address:
Note: Bits that are underlined are read-only; all other bits are read-write.
Bit 0/Force Resynchronization (RESYNC). A low-to-high transition forces the receive BERT synchronizer to
resynchronize to the incoming data stream. This bit should be toggled from low to high whenever the host wishes
to acquire synchronization on a new pattern. It must be cleared and set again for a subsequent resynchronization.
Note: Bits 2, 3, and 4 must be set, minimum of 64 system clock cycles, before toggling the resync bit (bit 0).
Bit 1/Load Bit and Error Counters (LC). A low-to-high transition latches the current bit and error counts into
the host accessible registers BERTBC and BERTEC and clears the internal count. This bit should be toggled from
low to high whenever the host wishes to begin a new acquisition period. Must be cleared and set again for
subsequent loads.
Bit 2/Pattern Select Bit 0 (PS0); Bit 3/Pattern Select Bit 1 (PS1); Bit 4/Pattern Select Bit 2 (PS2)
Bit 5/Receive Invert Data Enable (RINV)
Bit 6/Transmit Invert Data Enable (TINV)
Bit 8/Repetitive Pattern Length Bit 0 (RPL0); Bit 9/Repetitive Pattern Length Bit 1 (RPL1);
Bit 10/Repetitive Pattern Length Bit 2 (RPL2); Bit 11/Repetitive Pattern Length Bit 3 (RPL3). RPL0 is the
LSB and RPL3 is the MSB of a nibble that describes the how long the repetitive pattern is. The valid range is 17
(0000) to 32 (1111). These bits are ignored if the receive BERT is programmed for a pseudorandom pattern. To
create repetitive patterns less than 17 bits in length, the user must set the length to an integer number of the desired
length that is less than or equal to 32. For example, to create a 6-bit pattern, the user can set the length to 18 (0001)
or 24 (0111) or 30 (1101).
000 = pseudorandom pattern 2E7 - 1
001 = pseudorandom pattern 2E11 - 1
010 = pseudorandom pattern 2E15 - 1
011 = pseudorandom pattern QRSS (2E20 - 1 with a 1 forced, if the next 14 positions are 0)
100 = repetitive pattern
101 = alternating word pattern
110 = illegal state
111 = illegal state
0 = do not invert the incoming data stream
1 = invert the incoming data stream
0 = do not invert the outgoing data stream
1 = invert the outgoing data stream
IESYNC
n/a
15
7
0
0
BERTC0
BERT Control Register 0
0500h
IEBED
TINV
14
6
0
0
RINV
IEOF
13
5
0
0
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PS2
n/a
12
4
0
0
RPL3
PS1
11
3
0
0
RPL2
PS0
10
2
0
0
RPL1
LC
1
0
9
0
RESYNC
RPL0
0
0
8
0