Programming Description

GENERAL PROGRAMMING INFORMATION

The serial interface has a 24-bit shift register to store the incoming data bits temporarily. The incoming data is first loaded into the

shift register from MSB to LSB. The data is shifted at the rising edge of the clock signal. When the latch enable signal transitions

from LOW to HIGH, the data stored in shift register is transferred to the proper register depending on the address bit setting. The

selection of the particular register is determined by the control bits indicated in boldface text.

At initial start-up, the MICROWIRE loading requires three default words (registers R2, loaded first, to R0, loaded last). After the

device has been initially programmed, the RF VCO frequency can be changed using a single register (R0).

The control register content map describes how the bits within each control register are allocated to the specific control functions.

COMPLETE REGISTER MAP

MSB

SHIFT REGISTER BIT LOCATION

LSB

23

22

21

20

19

18

17

16

15

14

13

12

11

10

9876

5

4

3

2

1

0

R0

(Default)

RX/

TX

RF_

PD

HS

0

BS

RF_B

[3:0]

RF_A

[2:0]

RF_FN

[9:0]

00

R1

(Default)

SPI_

DEF

0

0

10

01010000

0

010LDOB_

CRL

[1:0]

OSC_

FREQ

[1:0]

01

R2

(Default)

1

1

0

0

1

00001111

0

0000

0

0

0

1

10

R3

1

0

0

0

0

11010000

0

0000

0

1

1

01

1

R4

0

0

0

0

0

01110100

0

1100

1

0

011

1

R5

0

0

0

0

0

00000000

0

0000

0

0

111

1

Note: R0 control register will be used when hot start frequency change.

Note: Boldface text represent address bits.

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