Description of Operation
8-38
ADSP-BF537 Blackfin Processor Hardware Reference
The CRC-16 hash value for a sequence of bytes may be calculated serially,
with each byte processed LSB-first. The initial value of the CRC state is
0xFFFF (all 1s). For each input bit, the LFSR is shifted left one position,
and the bit shifted out is XORed with the new input bit. The resulting
feedback bit is then XORed into the LFSR at bit positions 15, 2, and 1.
Thus the generator polynomial for this CRC is:
G(x) = x
16
+ x
15
+ x
2
+ 1
For example, if the wakeup pattern specified the single byte 0x12, or
0100_1000 (LSB first), the calculation of the wakeup CRC_16 is per-
formed as shown in
G polynomial = 1000 0000 0000 0101
Ethernet Event Interrupts
The Ethernet event interrupt is signalled to indicate that any or all of the
conditions listed below are pending.
interrupts. In the ADSP-BF536 and ADSP-BF537, the Ethernet event
Table 8-7. CRC-16 Hash Value Calculation
Bit In
XOR
MSB Bit
Feedback
Bit
CRC State
1111 1111 1111 1111,
Initial = 0xFFFF
0
1
1
0111 1111 1111 1011
1
0
1
0111 1111 1111 0011
0
0
0
1111 1111 1110 0110
0
1
1
0111 1111 1100 1001
1
0
1
0111 1111 1001 0111
0
0
0
1111 1111 0010 1110
0
1
1
0111 1110 0101 1001
0
0
0
1111 1100 1011 0010,
Final = 0xFCB2
Summary of Contents for Blackfin ADSP-BF537
Page 42: ...Contents xlii ADSP BF537 Blackfin Processor Hardware Reference ...
Page 90: ...Development Tools 1 32 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 138: ...Programming Examples 4 26 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 340: ...SDC Programming Examples 6 84 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 606: ...Programming Examples 9 94 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 660: ...Programming Examples 10 54 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 720: ...Electrical Specifications 11 60 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 840: ...Programming Examples 13 42 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 876: ...Programming Examples 14 36 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 938: ...Programming Examples 15 62 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 958: ...Programming Examples 17 12 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 986: ...Programming Examples 18 28 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 1162: ...G 26 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 1218: ...Index I 56 ADSP BF537 Blackfin Processor Hardware Reference ...