Texas Instruments CC2500 User Manual

CC2500
S
WRS040
C
Page
72
of
89
0x
18: MCSM0
–
Main Radio Control State
Machine C
onfiguration
Bit
Field Name
Reset
R/W
Description
7:6
Reserved
R0
5:4
FS_AUTOCAL[1:0]
0 (00)
R/W
Automatically calibrate when going to RX or TX, or back to IDLE
Setting
When to perform automatic calibration
0 (00)
Never
(manually calibrate using SCAL strobe
)
1 (01)
When going from IDLE to RX or TX (or FSTXON)
2 (10)
When going from RX or TX back to IDLE
automatically
3 (11)
Every 4
th
time when going from RX or TX to IDLE
automatically
In some automatic
wake
-
on
-
radio (WOR) applications, using
setting 3 (11) can significantly reduce current consumption.
3:2
PO_TIMEOUT
1 (01)
R/W
Programs the number of times the six
-
bit ripple coun
ter must
expire after XOSC has stabilized before
CHP_RDYn
goes low.
If
XOSC
is on (stable) during
power
-
down,
PO_TIMEOUT
should be set so that
the regulated digital supply voltage
has
time
to stabilize before
CHP_RDYn
goes low
(
PO_TIMEOUT
=
2
recommended)
.
Typical start
-
up time for the voltage regulator is
50 us.
If
XOSC
is off dur
ing
power
-
down
and
the regulated digital
supply voltage has
sufficient
time to stabilize while waiting for
the crystal to be stable
,
PO_TIMEOUT
can be set to
0
.
For
robust operation it is
recommended to use
PO_TIMEOUT=
2
.
Setting
Expire count
Timeout after
XOSC start
0 (00)
1
Approx. 2.3
–
2.4
μs
1 (01)
16
Approx. 37
–
39
μs
2 (10)
64
Approx. 14
9
–
1
55
μs
3 (11)
256
Approx. 5
97
–
6
20
μs
Exact timeout depends on crystal frequency.
1
PIN_CTRL_EN
0
R/W
Enables the pin radio control option
0
XOSC_FORCE_ON
0
R/W
Force the XOSC to stay on in the SLEEP state.

Texas Instruments CC2500 Specifications

General

Brand	Texas Instruments
Model	CC2500
Category	Transceiver
Language	English