Jameco Electronics Rabbit 3000 - Manual (Page 122)

User’s Manual 113
Table 7-26. Quadrature Decoder Control Register
Quad Decode Control Register (QDCR) (Address = 0x91)
Bit(s) Value Description
7:6
00
Disable Quadrature Decoder 2 inputs. Writing a new value to these bits will not
cause Quadrature Decoder 2 to increment or decrement.
01 This bit combination is reserved and should not be used.
10 Quadrature Decoder 2 inputs from Port F bits 3 and 2.
11 Quadrature Decoder 2 inputs from Port F bits 7 and 6.
5:4 These bits are ignored.
3:2
00
Disable Quadrature Decoder 1 inputs. Writing a new value to these bits will not
cause Quadrature Decoder 1 to increment or decrement.
01 This bit combination is reserved and should not be used.
10 Quadrature Decoder 1 inputs from Port F bits 1 and 0.
11 Quadrature Decoder 1 inputs from Port F bits 5 and 4.
1:0
00 Quadrature Decoder interrupts are disabled.
01 Quadrature Decoder interrupt use Interrupt Priority 1.
10 Quadrature Decoder interrupt use Interrupt Priority 2.
11 Quadrature Decoder interrupt use Interrupt Priority 3.
Table 7-27. Quadrature Decoder Count Register
Quad Decode Count Register (QDC1R) (Address = 0x94)
(QDC2R) (Address = 0x96)
Bit(s) Value Description
7:0 read The current value of the Quadrature Decoder counter is reported.