CC2510FX Datasheet, PDF (192/244 Pages) List of Unclassifed Manufacturers – True System-on-Chip with Low Power RF Transceiver and 8051 MCU

C2510Fx / CC2511Fx
; Transmit the following data: 0x02, 0x12, 0x34
; (Assume that the radio has already been configured, the high speed
; crystal oscillator is selected as system clock, and CLKCON.CLKSPD=000)
MOV RFST,#03H
C1: JNB RFTXRXIE,C1
CLR RFTXRXIE
MOV RFD,#02H
C2: JNB RFTXRXIE,C2
CLR RFTXRXIE
MOV RFD,#12H
C3: JNB RFTXRXIE,C3
CLR RFTXRXIE
MOV RFD,#34H
; Start TX with STX command strobe
; Wait for interrupt flag telling radio is
; ready to accept data, then write first
; data byte to radio (packet length = 2)
; Wait for radio
;
; Send first byte in payload
; Wait for radio
;
; Send second byte in payload
; Done
Figure 48: Simple RF Transmit Example
14.5 Data Rate Programming
The data rate used when transmitting, or the
data rate expected in receive is programmed
by the MDMCFG3.DRATE_M and the
MDMCFG4.DRATE_E configuration registers.
The data rate is given by the formula below.
( ) _{RDATA =}
256 + DRATE _ M
2²⁸
⋅ 2^{DRATE _ E} _{⋅ fref}
The following approach can be used to find
suitable values for a given data rate:
14.6 Receiver Channel Filter Bandwidth
In order to meet different channel width
requirements, the receiver channel filter is
programmable. The MDMCFG4.CHANBW_E and
MDMCFG4.CHANBW_M configuration registers
control the receiver channel filter bandwidth.
The following formula gives the relation
between the register settings and the channel
filter bandwidth:
BW_channel
=
f _ref
8 ⋅ (4 + CHANBW_
M )·2^{CHANBW_ E}
For best performance, the channel filter
bandwidth should be selected so that the
signal bandwidth occupies at most 80% of the
channel filter bandwidth. The channel centre
tolerance due to crystal accuracy should also
DRATE
_
E
=
⎢
⎢log₂
⎢⎣
⎜⎜⎝⎛
R_DATA ⋅
f _ref
2²⁰
⎟⎟⎠⎞⎥⎥⎦⎥
DRATE _ M
=
R_DATA ⋅ 2²⁸
f_ref ⋅ 2^{DRATE _ E}
− 256
If DRATE_M is rounded to the nearest integer
and becomes 256, increment DRATE_E and
use DRATE_M=0.
be subtracted from the signal bandwidth. The
following example illustrates this:
With the channel filter bandwidth set to 600
kHz, the signal should stay within 80% of 600
kHz, which is 480 kHz. Assuming 2.44 GHz
frequency and ±20 ppm frequency uncertainty
for both the transmitting device and the
receiving device, the total frequency
uncertainty is ±40 ppm of 2.44 GHz, which is
±98 kHz. If the whole transmitted signal
bandwidth is to be received within 480 kHz, the
transmitted signal bandwidth should be
maximum 480 kHz – 2·98 kHz, which is 284
kHz.
The CC2510Fx/CC2511Fx supports channel filter
bandwidths shown in Table 62 and Table 63
respectively.
SWRS055D
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