DS33R11 Ethernet Mapper with Integrated T1/E1/J1 Transceiver

10.26 Payload Error-Insertion Function (T1 Mode Only)

An error-insertion function is available in the transceiver and is used to create errors in the payload portion of the T1 frame in the transmit path. This function is only available in T1 mode. Errors can be inserted over the entire frame or the user can select which channels are to be corrupted. Errors are created by inverting the last bit in the count sequence. For example, if the error rate 1 in 16 is selected, the 16th bit is inverted. F-bits are excluded from the count and are never corrupted. Error rate changes occur on frame boundaries. Error-insertion options include continuous and absolute number with both options supporting selectable insertion rates.

Table 10-14. Transmit Error-Insertion Setup Sequence

STEP

ACTION

1Enter desired error rate in the TR.ERC register. Note: If TR.ER3 through TR.ER0 = 0, no errors are generated even if the constant error-insertion feature is enabled.

2A

For constant error insertion, set CE = 1 (TR.ERC.4).

or

 

2B

For a defined number of errors:

Set CE = 0 (TR.ERC.4)

Load TR.NOE1 and TR.NOE2 with the number of errors to be inserted

Toggle WNOE (TR.ERC.7) from 0 to 1 to begin error insertion

10.26.1Number-of-Errors Registers

The number-of-error registers determine how many errors are generated. Up to 1023 errors can be generated. The host loads the number of errors to be generated into the TR.NOE1 and TR.NOE2 registers. The host can also update the number of errors to be created by first loading the prescribed value into the TR.NOE registers and then toggling the WNOE bit in the error-rate control registers.

Table 10-15. Error Insertion Examples

VALUE

WRITE

READ

 

 

 

000h

Do not create any errors

No errors left to be inserted

001h

Create a single error

One error left to be inserted

002h

Create two errors

Two errors left to be inserted

3FFh

Create 1023 errors

1023 errors left to be inserted

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Maxim DS33R11 specifications Payload Error-Insertion Function T1 Mode Only, Transmit Error-Insertion Setup Sequence