MRF39RA Datasheet, PDF (23/72 Pages) Microchip Technology – Low-Power, Integrated UHF Receiver

3.3.1 Timings
The duration of the idle phase is given by t_ListenIdle. The
time during which the receiver is on and is waiting for a
signal is given by t_ListenRx. The t_ListenRx includes the
wake-up time of the receiver as described in
Section 3.2.1 “Receiver Start-up Time”. This
duration is programmed in the Configuration registers
via the serial interface.
Both time periods t_ListenRx and t_ListenIdle (denoted
t_ListenX in the text below) are fixed by two parameters
from the Configuration register and are calculated as
follows:
EQUATION 3-1: TIME PERIODS
t_ListenX = ListenCoefX  ListenResolX
Where:
ListenResolX is the Rx or idle resolution and is
independently programmable on three values (64 µs,
4.1 ms or 262 ms), whereas ListenCoefX is an
integer between 1 and 255. All parameters are
located in RegListen registers.
The timing ranges are tabulated in Table 3-2.
TABLE 3-2:
RANGE OF DURATIONS IN
LISTEN MODE
ListenResolX
Min duration
(ListenCoef = 1)
Max duration
(ListenCoef = 255)
01
64 µs
10
4.1 ms
11
0.26s
16 ms
1.04s
67s
Note 1: The accuracy of the typical timings given
in Table 3-2 depends on the RC oscillator
calibration.
2: RC oscillator calibration is required and
must be performed at power-up. See
Section 3.3.5 “RC Timer Accuracy” for
details.
MRF39RA
 2015 Microchip Technology Inc.
DS40001778B-page 23