Texas Instruments 3138 155 232931 - Manual (Page 66)

CC2420
SWRS041B Page 66 of 89
SYNCWORD (0x14) - Sync Word
Bit Field Name Reset R/W Description
15:0 SYNCWORD[15:0] 0xA70F R/W Synchronisation word. The SYNCWORD is processed from the
least significant nibble (F at reset) to the most significant nibble
(A at reset).
SYNCWORD
is used both during modulation (where 0xF’s are
replaced with 0x0’s) and during demodulation (where 0xF’s are
not required for frame synchronisation). In reception an implicit
zero is required before the first symbol required by SYNCWORD.
The reset value is compliant with IEEE 802.15.4.
TXCTRL (0x15) - Transmit Control Register
Bit Field Name Reset R/W Description
15:14 TXMIXBUF_CUR[1:0] 2 R/W TX mixer buffer bias current.
0: 690uA
1: 980uA
2: 1.16mA (nominal)
3: 1.44mA
13 TX_TURNAROUND 1 R/W Sets the wait time after STXON before transmission is started.
0 : 8 symbol periods (128 us)
1 : 12 symbol periods (192 us)
12:11 TXMIX_CAP_ARRAY[1:0] 0 R/W Selects varactor array settings in the transmit mixers.
10:9 TXMIX_CURRENT[1:0] 0 R/W Transmit mixers current:
0: 1.72 mA
1: 1.88 mA
2: 2.05 mA
3: 2.21 mA
8:6 PA_CURRENT[2:0] 3 R/W Current programming of the PA
0: -3 current adjustment
1: -2 current adjustment
2: -1 current adjustment
3: Nominal setting
4: +1 current adjustment
5: +2 current adjustment
6: +3 current adjustment
7: +4 current adjustment
5 - 1 W1 Reserved, write as 1.
4:0 PA_LEVEL[4:0] 31 R/W Output PA level. (~0 dBm)