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Rainbow Electronics DS26504 User Manual

Page 36

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DS26504 T1/E1/J1/64KCC BITS Element

36 of 128


Register Name:

TPCR1

Register Description:

Transmit PLL Control Register 1

Register Address:

09h


Bit

# 7 6 5 4 3 2

1

0

Name

TPLLOFS1 TPLLOFS0 PLLOS TPLLIFS1 TPLLIFS0 TPLLSS TCSS1 TCSS0

Default

0 0 0 0 0 0

0

0

HW
Mode

0 0 0 0 0 0

TCSS1
PIN 31

TCSS0
PIN 63


For more information on all the bits in the Transmit PLL control register, refer to

Figure 3-3

.


Bits 0 and 1: Transmit Clock (TX CLOCK) Source Select (TCSS[0:1]). These bits control the output of the TX PLL
Clock Mux function. See

Figure 3-3

.

TCSS1 TCSS0

TRANSMIT CLOCK (TX CLOCK) SOURCE

(See

Figure 3-3

)

0

0

The TCLK pin is the source of transmit clock.

0

1

The PLL_CLK is the source of transmit clock.

1

0

The scaled signal present at MCLK as the transmit clock.

1

1

The signal present at RCLK is the transmit clock.


Bit 2: Transmit PLL_CLK Source Select (TPLLSS). Selects the reference signal for the TX PLL.

0 = Use the recovered network clock. This is the same clock available at the RCLK pin (output).

1 = Use the externally provided clock present at the TCLK pin.


Bit 3 and 4: Transmit PLL Input Frequency Select (TPLLIFS[0:1]).
These bits, along with TPLLIFS2 (TPCR2.0), are
used to indicate the reference frequency being input to the TX PLL.

TPLLIFS2
(TPCR2.0)

TPLLIFS1 TPLLIFS0

TX PLL INPUT

FREQUENCY

0 0 0

1.544MHz

0 0 1

2.048MHz

0 1 0

64kHz

0 1 1

6312kHz

1 0 0

8kHz

1 0 1

19.44MHz


Bit 5: PLL_OUT Select (PLLOS). This bit selects the source for the PLL_OUT pin. See

Figure 3-3

.

0 = PLL_OUT is sourced directly from the TX PLL.
1 = PLL_OUT is the output of the TX PLL mux.

Bits 6 and 7: Transmit PLL Output Frequency Select (TPLLOFS[0:1]). These bits, along with TPLLOFS1 (TPCR2.1),
are used to select the TX PLL output frequency.

TPLLOFS2

(TPCR2.1)

TPLLOFS1 TPLLOFS0

TX PLL OUTPUT

FREQUENCY

0 0 0

1.544MHz

0 0 1

2.048MHz

0 1 0

64kHz

0 1 1

6312kHz

1 0 0

8kHz

1 0 1

19.44MHz