MRF39RA Datasheet, PDF (48/72 Pages) Microchip Technology – Low-Power, Integrated UHF Receiver

MRF39RA
TABLE 5-3: RECEIVER REGISTERS (CONTINUED)
Name
(Address)
Bits
Variable Name
Mode
Default
Value
Description
RegAfcFei
(0x1E)
7—
6 FeiDone
5 FeiStart
4 AfcDone
3 AfcAutoclearOn
2 AfcAutoOn
RegAfcMsb
(0x1F)
RegAfcLsb
(0x20)
RegFeiMsb
(0x21)
RegFeiLsb
(0x22)
RegRssiConfig
(0x23)
1 AfcClear
0 AfcStart
7-0 AfcValue(15:8)
7-0 AfcValue(7:0)
7-0 FeiValue(15:8)
7-0 FeiValue(7:0)
7-2 —
1 RssiDone
RegRssiValue
(0x24)
0 RssiStart
7-0 RssiValue
r
0 Unused
r
0 0  FEI is on-going
1  FEI finished
w
0 Triggers a FEI measurement when set.
Always reads ‘0’.
r
1 0  AFC is on-going
1  AFC has finished
rw
0 Only valid if AfcAutoOn is set
0  AFC register is not cleared before a
new AFC phase
1  AFC register is cleared before a
new AFC phase
rw
0 0  AFC is performed each time
AfcStart is set
1  AFC is performed each time Rx
mode is entered
w
0 Clears the AfcValue if set in Rx mode.
Always reads ‘0’.
w
0 Triggers an AFC when set. Always reads
‘0’.
r
0x00 MSB of the AfcValue, two’s complement
format
r
0x00 LSB of the AfcValue, two’s complement
format
Frequency correction = AfcValue x Fstep
r
— MSB of the measured frequency offset,
two’s complement
r
— LSB of the measured frequency offset,
two’s complement
Frequency error = FeiValue x Fstep
r 000000 Unused
r
1 0  RSSI is on-going
1  RSSI sampling is finished, result
available
w
0 Trigger a RSSI measurement when set.
Always reads ‘0’.
r
0xFF Absolute value of the RSSI in dBm,
0.5 dB steps.
RSSI = -RssiValue/2 [dBm]
DS40001778B-page 48
 2015 Microchip Technology Inc.