STA015 datasheet(19/55 Pages) STMICROELECTRONICS

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STA015 STA015B STA015T

UPD_FRAC: when is set to 1, update FRAC in the switching circuit. It is set to 1 after autoboot.

XTI2OCLK: when is set to 1, use the XTI as input of the divider X instead of VCO output. It is set to 0 on

HW reset.

XTI2DSPCLK: when is to 1, set use the XTI as input of the divider S instead of VCO output. It is set to 0

on HW reset.

PLLDIS: when set to 1, the VCO output is disabled. It is set to 0 on HW reset.

SYS2OCLK: when is set to 1, the OCLK frequency is equal to the system frequency. It is useful for testing.

It is set to 0 on HW reset.

OCLKEN: when is set to 1, the OCLK pad is enable as output pad. It is set to 1 on HW reset.

XTODIS: when is set to 1, the XTO pad is disable. It is set to 0 on HW reset.

XTO_BUF: when this bit is set, the pin nr. 28 (OUT_CLOCK/DATA_REQ) is enabled. It is set to 0 after

autoboot.

PLLCTL (M)

Address: 0x06 (06)

Type: R/W

Software Reset: 0x0C

Hardware Reset: 0x0C

PLLCTL (N)

Address: 0x07 (07)

Type: R/W

Software Reset: 0x00

Hardware Reset: 0x00

The M and N registers are used to configure the STA015 PLL by DSP embedded software.

M and N registers are R/W type but they are completely controlled, on STA015, by DSP software.

REQ_POL

Address: 0x0C (12)

Type: R/W

Software Reset: 0x01

Hardware Reset: 0x00

The REQ_POL registers is used to program the polarity of the DATA_REQ line.

Default polarity (the source sends data when the DATA_REQ line is high)

Inverted polarity (the source sends data when the ATA_REQ line is low)

MSB

LSB

000001

MSB

LSB

000101

STA015 Datasheet(PDF) 19 Page - STMicroelectronics