Rf12 – Rainbow Electronics RF12 User Manual

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RF12

1 0 0

2.5

1 0 1

3.33

1 1 0

1 1 1

The low battery detector and the clock output can be enabled or disabled by bits eb and dc, respectively,

using the Power Management Command.

15. Status Read Command

The read command starts with a zero, whereas all other control commands start with a one. If a read

command is identified, the status bits will be clocked out on the SDO pin as follows:

Status Register Read Sequence with FIFO Read Example:

RGIT

TX register is ready to receive the next byte (Can be cleared by Transmitter

FFIT

The number of data bits in the RX FIFO has reached the pre-programmed limit (Can

be cleared by any of the FIFO read methods)

POR

Power-on reset (Cleared after Status Read Command )

RGUR

TX register under run, register over write (Cleared after Status Read Command )

FFOV

RX FIFO overflow (Cleared after Status Read Command )

WKUP

Wake-up timer overflow (Cleared after Status Read Command )

EXT

Logic level on interrupt pin (pin 16) changed to low (Cleared after Status Read

Command )

LBD

Low battery detect, the power supply voltage is below the pre-programmed limit

FFEM

FIFO is empty

ATS

Antenna tuning circuit detected strong enough RF signal

RSSI

The strength of the incoming signal is above the pre-programmed limit

DQD

Data quality detector output

CRL

Clock recovery locked

ATGL

Toggling in each AFC cycle

OFFS(6)

MSB of the measured frequency offset (sign of the offset value)

OFFS(3)-OFFS(0)

Offset value to be added to the value of the frequency control parameter (Four LSB

bits)

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