beautypg.com

Bits – Texas Instruments TMS320C645X User Manual

Page 113

background image

www.ti.com

SRIO Registers

Table 40. SERDES Receive Channel Configuration Registers n (SERDES_CFGRXn_CNTL) Field

Descriptions (continued)

Bit

Field

Value

Description

11

Reserved

Reserved.

10:8

TERM

Termination. Selects input termination options suitable for a variety of AC or DC coupled
scenarios.

000

Common point connected to VDDT. This configuration is for DC coupled systems using CML
transmitters. The common mode voltage is determined jointly by both the receiver and the
transmitter. Common mode termination is via a 50pF capacitor to VSSA.

001

Common point set to 0.8 VDDT. This configuration is for AC coupled systems using CML
transmitters. The transmitter has no effect on the receiver common mode, which is set to optimize
the input sensitivity of the receiver. Common mode termination is via a 50pF capacitor to VSSA.

010

Reserved

011

Common point floating. This configuration is for DC coupled systems that require the common
mode voltage to be determined by the transmitter only. These are typically not CML. Common
mode termination is via a 50pF capacitor to VSSA.

1xx

Reserved

7

INVPAIR

Invert polarity. Inverts polarity of RXPI and RXNn.

0

Normal polarity. RXPn considered to be positive data and RXNi negative.

1

Inverted polarity. RXPn considered to be negative data and RXNn positive.

6:5

RATE

Operating rate. Selects full, half or quarter rate operation.

00

Full rate. Two data samples taken per PLL output clock cycle.

01

Half rate. One data sample taken per PLL output clock cycle.

10

Quarter rate. One data sample taken every two PLL output clock cycles.

11

Reserved

4:2

BUS-

Bus width. Selects the width of the parallel interface (10 or 8 bit).

WIDTH

000

10-bit operation. Data is output on RDn[9:0]. RXBCLK[n] period is 10 bit periods (4 high, 6 low).

001

8-bit operation. Data is output on RDn[7:0]. RXBCLK[n] period is 8 bit periods (4 high, 4 low).
RDn[9:8] will replicate bits [1:0] from the previous byte.

01x

Reserved

1xx

Reserved

1

Reserved

Reserved, keep as zero during writes to this register.

0

ENRX

Enable receiver. Enables this receiver when high.

0

Disable

1

Enable

Table 41. EQ Bits

CFGRX[22:19]

Low Freq Gain

Zero Freq (at e

28

(min))

0000

Maximum

-

0001

Adaptive

Adaptive

001x

Reserved

01xx

Reserved

1000

Adaptive

1084MHz

1001

805MHz

1010

573MHz

1011

402MHz

1100

304MHz

1101

216MHz

1110

156MHz

1111

135MHz

SPRU976 – March 2006

Serial RapidIO (SRIO)

113

Submit Documentation Feedback