BK4811 V 0.2
© 2012 Beken Corporation Proprietary and Confidential Page 7 of 35
Note
1. By default, the BK4811 will cover 400~500 MHz, 266~333 MHz and 134~250
MHz; For other special band, please ask Beken for the proper version
To set the RF frequency with REG113 and REG114, please using the procedure
as follows.
1. Set theREG126 and REG127 according to table above and REG3[15:13]=0
2. Set the REG113 and REG114 as follow.
)__/23^2**(_ IFNREFFDIVfroundRFN
; Where F_REF is the crystal
frequency in Hz, and f is the RF frequency in Hz (for wideband, the f should be
RF frequency subtracted by 3125. The REG113 is the 16 bits MSBs and the
REG114 is the 16 bits LSBs of the N_RF.
3. Toggle the REG5[10] with 0, 1, 0 sequence
4. Set the REG3[15:13] according to the table 1
To avoid image frequency interference, user can change the IF to the opposite as
follows.
5. REG117[10]=0,read RSSI0 of F0=(Fwanted - 2*IF)
6. REG117[10]=1,read RSSI1 of F1=(Fwanted + 2*IF), where
REG113/REG113= f(Fwanted+2*IF+2*IF), where f is the formula to calculate
the REG113/REG114 in step 2
7. If RSSI0<RSSI1,REG117[10]=0,else REG117[10]=1
8. If REG117[10]=0, REG113/REG114 = f(Fdesired), has the same formula as
step 2; If REG117[10]=1, REG113/REG114 = f(Fdesired + 2*IF);