CC2420
SWRS041B Page 81 of 89
38 Test Output Signals
The two digital output pins
CCA
and
SFD
,
can be set up to output test signals
defined by
IOCFG1.CCAMUX
and
IOCFG1.SFDMUX
. This is summarized in
Table 12 and Table 13 below.
CCAMUX
Signal output on
CCA
pin
Description
0 CCA
Normal
operation
1
ADC_Q[0]
ADC, Q-branch, LSB used for random number generation
2
DEMOD_RESYNC_LATE
High one 16 MHz clock cycle each time the demodulator
resynchronises late
3
LOCK_STATUS
Lock status, same as
FSCTRL.LOCK_STATUS
4
MOD_CHIPCLK
Chip rate clock signal during transmission
5
MOD_SERIAL_CLK
Bit rate clock signal during transmission
6 FFCTRL_FS_PD
Frequency
synthesizer power down, active high
7
FFCTRL_ADC_PD
ADC power down, active high
8
FFCTRL_VGA_PD
VGA power down, active high
9
FFCTRL_RXBPF_PD
Receiver bandpass filter power down, active high
10
FFCTRL_LNAMIX_PD
Receiver LNA / Mixer power down, active high
11
FFCTRL_PA_P_PD
Power amplifier power down, active high
12
AGC_UPDATE
High one 16 MHz clock cycle each time the AGC updates its gain
setting
13
VGA_PEAK_DET[1]
VGA Peak detector, gain stage 1
14
VGA_PEAK_DET[3]
VGA Peak detector, gain stage 3
15 AGC_LNAMIX_GAINMODE[1]
RF
receiver front-end gain mode, bit 1
16
AGC_VGA_GAIN[1]
VGA gain setting, bit 1
17 VGA_RESET_N
VGA
peak-detector reset sign, active low.
18 -
Reserved
19 -
Reserved
20 -
Reserved
21 -
Reserved
22 -
Reserved
23
CLK_8M
8 MHz clock signal output
24
XOSC16M_STABLE
16 MHz crystal oscillator stabilised, same as the status bit in Table
5
25 FSDIG_FREF
Frequency
synthesizer, 4 MHz reference signal
26 FSDIG_FPLL
Frequency
synthesizer, 4 MHz divided signal
27 FSDIG_LOCK_WINDOW Frequency
synthesizer, lock window
28
WINDOW_SYNC
Frequency synthesizer, synchronized lock window
29
CLK_ADC
ADC clock signal 1
30 ZERO
Low
31 ONE
High
Table 12. CCA test signal select table