Rainbow Electronics AT86RF211 User Manual

Page 28

AT86RF211

1942C–WIRE–06/02

Notes:

1. The same ADC is used to measure RSSI or V

voltage. When the V

voltage is measured, the RSSI measurement is

stopped (previously measured RSSI is kept into STATUS Register). This can disturb the reception process (if a threshold is
used for DATAMSG validation). So, it is not recommended to measure V

in reception mode.

2. V

measurement can not be done when the AT86RF211 is in power-down mode.

3. While in V

measurement, it is possible to measure the DC output of the discriminator.

4. Description of RSSI measurement with hysteresis mechanism: if the RSSI measurement is higher than the high RSSI level,

DATAMSG is validated (high RSSI level = TRSSI + HRSSI). If the RSSI measure is lower than the low RSSI level, DATA-
MSG is inhibited (low RSSI level = TRSSI - HRSSI). Between these two levels, DATAMSG validation depends on the
previous measurement.
Example:
TRSSI = 32 and HRSSI = 4 implies High RSSI level = 26 and Low RSSI level = 28

–

reserved, must be kept to reset value: 0

RXFS

RX frequency selection
(00)

: F0

(10)

: F2

(01)

: F1

(11)

: F3

reset value: (10)

XTALFQ

Crystal frequency
0: 10.245 MHz (when IF1 = 10.7 MHz)
1: 20.945 MHz (when IF1 = 21.4 MHz)

reset value: 0

FSKBW

Discriminator range
0: Narrow Discriminator BW

1: Standard Discriminator BW

reset value: 1

FSKPOL

Polarity of DATAMSG
0: inverted signal
1: direct signal

reset value: 1

DSREF

Data Slicer reference voltage
0: external reference: SKFILT pin voltage
1: internal reference: DAC level voltage

reset value: 1

–

reserved, must be kept to reset value: 0

–

reserved, must be kept to reset value: 0

MOFFSET

0: internal ADC sets to V

measurement

1: internal ADC sets to DISCOUT DC level measurement

reset value: 0

–

reserved, must be kept to reset value: 0

MRSSI sequence

RSSI level

NOK

DATAMSG

valid

Table 6. CTRL1 Detailed Description

(1)(2)(4)(3)

(Continued)

Name

Number

of Bits

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