User guide

DS3134

73 of 203

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 to 24 (0111) or to 30 (1101).

Repetitive Pattern Length Map

Length Code Length Code Length Code Length Code

17 Bits 0000 18 Bits 0001 19 Bits 0010 20 Bits 0011

21 Bits 0100 22 Bits 0101 23 Bits 0110 24 Bits 0111

25 Bits 1000 26 Bits 1001 27 Bits 1010 28 Bits 1011

29 Bits 1100 30 Bits 1101 31 Bits 1110 32 Bits 1111

Bit 13 / Interrupt Enable for Counter Overflow (IEOF). Allows the receive BERT to cause an

interrupt if either the Bit Counter or the Error Counter overflows.

0 = interrupt masked

1 = interrupt enabled

Bit 14 / Interrupt Enable for Bit Error Detected (IEBED). Allows the receive BERT to cause an

interrupt if a bit error is detected.

0 = interrupt masked

1 = interrupt enabled

Bit 15 / Interrupt Enable for Change of Synchronization Status (IESYNC). Allows the receive

BERT to cause an interrupt if there is a change of state in the synchronization status (i.e. the receive

BERT either goes into or out of synchronization).

0 = interrupt masked

1 = interrupt enabled

76543210

EIB2 EIB1 EIB0 SBE n/a n/a n/a TC

15 14 13 12 11 10 9 8

Alternating Word Count

Note: Bits that are underlined are read only, all other bits are read-write; default value for all bits is 0.

Bit 0 / Transmit Pattern Load (TC). A low to high transition loads the pattern generator with

Repetitive or pseudorandom pattern that is to be generated. This bit should be toggled from low to high

whenever the host wishes to load a new pattern. Must be cleared and set again for a subsequent loads.