Datasheet

dsPIC30F2011/2012/3012/3013

FIGURE 4-2: BIT-REVERSED ADDRESS EXAMPLE

TABLE 4-2: BIT-REVERSED ADDRESS SEQUENCE (16-ENTRY)

TABLE 4-3: BIT-REVERSED ADDRESS MODIFIER VALUES FOR XBREV REGISTER

Normal Address Bit-Reversed Address

A3 A2 A1 A0 Decimal A3 A2 A1 A0 Decimal

0000 0 0000 0

0001 1 1000 8

0010 2 0100 4

0011 3 1100 12

0100 4 0010 2

0101 5 1010 10

0110 6 0110 6

0111 7 1110 14

1000 8 0001 1

1001 9 1001 9

1010 10 0101 5

1011 11 1101 13

1100 12 0011 3

1101 13 1011 11

1110 14 0111 7

1111 15 1111 15

Buffer Size (Words) XB<14:0> Bit-Reversed Address Modifier Value

1024 0x0200

512 0x0100

256 0x0080

128 0x0040

64 0x0020

32 0x0010

16 0x0008

8 0x0004

4 0x0002

2 0x0001

b3 b2 b1 0

b2 b3 b4 0

Bit Locations Swapped Left-to-Right

Around Center of Binary Value

Bit-Reversed Address

XB = 0x0008 for a 16-word Bit-Reversed Buffer

b7 b6 b5 b1

b7 b6 b5 b4b11 b10 b9 b8

b11 b10 b9 b8

b15 b14 b13 b12

Sequential Address

Pivot Point