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Revision 1.2

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AS3932

All direct commands are explained below:

- clear_wake: clears the wake state of the chip. In case the chip has woken up (WAKE pin is high) the chip is set back to listening mode

- reset_RSSI: resets the RSSI measurement.

- trim_osc: starts the trimming procedure of the internal RC oscillator (see Figure 22)

- clear_false: resets the false wakeup register (R13=00)

- preset_default: sets all register in the default mode, as shown in Figure 7

8.3.3.2 Writing of Data to Addressable Registers (WRITE Mode)

The SDI is sampled at the falling edge of CLK (as shown in the following diagrams).

A CS toggling high-low-high indicates the end of the WRITE command after register has been written. The following example shows a write

command.

Figure 13. Writing of a Single Byte (falling edge sampling)

Figure 14. Writing of Register Data with Auto-incrementing Address

8.3.3.3 Reading of Data from Addressable Registers (READ Mode)

Once the address has been sent through SDI, the data can be fed through the SDO pin out to the microcontroller.

A CS LOW toggling high-low-high has to be performed after finishing the read mode session, in order to indicate the end of the READ command

and prepare the Interface to the next command control Byte.

To transfer bytes from consecutive addresses, SDI master has to keep the CS signal high and the SCLK clock has to be active as long as data

need to be read.

trim_osc

0

00010

clear_false

0

00011

preset_default

0

00100

Table 12. List of Direct Commands

COMMAND_MODE

B13

B12

B11

B10

B9

B8

CS

SCLK

SDI

0

0

A5

A4

A3

A2

A1

A0

D5

D 4

D3

D2

D1

D0

D7

D6

X

X

SCLK raising

edge Data is

transf ered from

µC

SCLK

falling edge

Data is

sampled

Data is moved

t o Address

A5-A0

CS falling

edge signals

end of

WRITE Mode

Two leading

Zeros indicate

WRITE Mode

CS

SCLK

SDI

00

A

5

A

4

A

3

A

2

A

1

A

0

D

5

D

4

D

3

D

2

D

1

D

0

D

7

D

6

X

X

Data is moved

t o Address

<A5-A0 > + n

CS falling

edge signals

end of

WRITE Mode

Two leading

Zeros indicat e

WRI TE Mode

D

5

D

4

D

3

D

2

D

1

D

0

D

7

D

6

D

7

D

6

D

5

D

4

D

3

D

2

D

1

D

0

D

7

D

6

D

1

D

0

Data is moved

to Addres s

<A5-A0 > + (n- 1)

Dat a is mov ed

to Addres s

<A5-A0> +1

Data is moved

t o Address

<A5-A0>