Texas Instruments 3138 155 232931 manual SECCTRL0 0x19 Security Control Register, SECMODE10

CC2420

SECCTRL0 (0x19) - Security Control Register

Bit	Field Name	Reset	R/W
15:10	-	0	W0
9	RXFIFO_PROTECTION	1	R/W
8	SEC_CBC_HEAD	1	R/W

7	SEC_SAKEYSEL	1	R/W
6	SEC_TXKEYSEL	1	R/W
5	SEC_RXKEYSEL	0	R/W
4:2	SEC_M[2:0]	1	R/W

1:0 SEC_MODE[1:0] 0 R/W

Description

Reserved, write as 0

Protection enable of the RXFIFO, see description in the RXFIFO overflow section on page 33. Should be cleared if MAC level security is not used or is implemented outside CC2420.

Defines what to use for the first byte in CBC-MAC (does not apply to CBC-MAC part of CCM):

0 : Use the first data byte as the first byte into CBC-MAC

1 : Use the length of the data to be authenticated (calculated as (the packet length field – SEC_TXL – 2) for TX or using SEC_RXL for RX) as the first byte into CBC-MAC (before the first data byte).

This bit should be set high for CBC-MAC 802.15.4 inline security.

Stand Alone Key select

0 : Key 0 is used

1 : Key 1 is used

TX Key select

0 : Key 0 is used

1 : Key 1 is used

RX Key select

0 : Key 0 is used

1 : Key 1 is used

Number of bytes in authentication field for CBC-MAC, encoded as (M-2)/2

0 : Reserved

1 : 4

2 : 6

3 : 8

4 : 10

5 : 12

6 : 14

7 : 16

Security mode

0 : In-line security is disabled

1 : CBC-MAC

2 : CTR

3 : CCM

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