SX1231
ADVANCED COMMUNICATIONS & SENSING
DATASHEET
7
TxStartCondition
rw
1
*
Defines the condition to start packet transmission :
0 Æ FifoLevel (i.e. the number of bytes in the FIFO
exceeds FifoThreshold)
RegFifoThresh
(0x3C)
1 Æ FifoNotEmpty (i.e. at least one byte in the FIFO)
6-0 FifoThreshold
rw
rw
0001111 Used to trigger FifoLevel interrupt.
7-4 InterPacketRxDelay
0000 After PayloadReady occurred, defines the delay between
FIFO empty and the start of a new RSSI phase for next
packet. Must match the transmitter’s PA ramp-down time.
- Tdelay = 0 if InterpacketRxDelay >= 12
RegPacketConfig2
(0x3D)
- Tdelay = (2InterpacketRxDelay) / BitRate otherwise
3
2
-
rw
w
0
0
unused
RestartRx
Forces a new RSSI phase to start a new packet reception.
Always reads 0.
1
AutoRxRestartOn
rw
1
Enables automatic Rx restart (RSSI phase) after
PayloadReady occurred and packet has been completely
read from FIFO:
0 Æ Off. RestartRx can be used.
1 Æ On. Rx automatically restarted after
InterPacketRxDelay.
0
AesOn
rw
0
Enable the AES encryption/decryption:
0 Æ Off
1 Æ On (payload limited to 66 bytes maximum)
1st byte of cipher key (MSB byte)
7-0 AesKey(127:120)
7-0 AesKey(119:112)
7-0 AesKey(111:104)
7-0 AesKey(103:96)
7-0 AesKey(95:88)
7-0 AesKey(87:80)
7-0 AesKey(79:72)
7-0 AesKey(71:64)
7-0 AesKey(63:56)
7-0 AesKey(55:48)
7-0 AesKey(47:40)
7-0 AesKey(39:32)
7-0 AesKey(31:24)
7-0 AesKey(23:16)
w
w
w
w
w
w
w
w
w
w
w
w
w
w
0x00
0x00
0x00
0x00
0x00
0x00
0x00
0x00
0x00
0x00
0x00
0x00
0x00
0x00
RegAesKey1
(0x3E)
2nd byte of cipher key
RegAesKey2
(0x3F)
rd byte of cipher key
th byte of cipher key
th byte of cipher key
th byte of cipher key
th byte of cipher key
th byte of cipher key
th byte of cipher key
RegAesKey3
(0x40)
3
4
5
6
7
8
9
RegAesKey4
(0x41)
RegAesKey5
(0x42)
RegAesKey6
(0x43)
RegAesKey7
(0x44)
RegAesKey8
(0x45)
RegAesKey9
(0x46)
10th byte of cipher key
11th byte of cipher key
12th byte of cipher key
13th byte of cipher key
14th byte of cipher key
RegAesKey10
(0x47)
RegAesKey11
(0x48)
RegAesKey12
(0x49)
RegAesKey13
(0x4A)
RegAesKey14
(0x4B)
Rev 2 - Nov 2009
Page 71
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