DS2172

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7.0 ERROR INSERT REGISTER

The Error Insertion Register (EIR) controls circuitry within the DS2172 that allows the generated pattern

to be intentionally corrupted. Bit errors can be inserted automatically at regular intervals by properly

programming the EIR0 to EIR2 bits or bit errors can be inserted at random (under microcontroller

control) via the EIR.3 bit.

EIR: ERROR INSERT REGISTER (Address=07 Hex)

(MSB)

(LSB)

-

-

TINV

RINV

SBE

EIR2

EIR1

EIR0

SYMBOL

POSITION

NAME AND DESCRIPTION

-EIR.7

Not Assigned. Should be set to 0 when written to.

-EIR.6

Not Assigned. Should be set to 0 when written to.

TINV

EIR.5

Transmit Data Inversion Select.

0 = do not invert data to be transmitted at TDATA

1 = invert data to be transmitted at TDATA

RINV

EIR.4

Receive Data Inversion Select.

0 = do not invert data received at RDATA

1 = invert data received at RDATA

SBE

EIR.3

Single Bit Error Insert. A low to high transition will create a

single bit error. Must be cleared and set again for a subsequent

bit error to be inserted. Can be used to accomplish rates not

addressed in Table 3 (e.g., BER of less than 10

EIB2

EIR.2

Error Insert Bit 2. See Table 3.

EIB1

EIR.1

Error Insert Bit 1. See Table 3.

EIB0

EIR.0

Error Insert Bit 0. See Table 3.

ERROR BIT INSERTION Table 3

EIB2

EIB1

EIB0

ERROR RATE INSERTED

0

0

0

no errors automatically inserted

00

1

10

-1

01

0

10

-2

01

1

10

-3

10

0

10

-4

10

1

10

-5

11

0

10

-6

11

1

10

-7