Table 7-25. Quadrature Decoder Control/Status Register

Quad Decode Control/Status Register

(QDCSR)

(Address = 0x90)

 

 

 

 

 

Bit(s)

Value

 

Description

 

 

 

 

 

7

0

Quadrature Decoder 2 did not increment from 0xFF.

 

 

 

 

(read-only)

1

Quadrature Decoder 2 incremented from 0xFF to 0x00. This bit is cleared by a

read of his register.

 

 

 

 

 

 

 

 

 

 

6

0

Quadrature Decoder 2 did not decrement from 0x00.

 

 

 

 

(read-only)

1

Quadrature Decoder 2 decremented from 0x00 to 0xFF. This bit is cleared by a

read of this register.

 

 

 

 

 

 

 

 

 

 

 

5

 

This bit always reads as zero.

 

 

 

 

 

 

4

0

No effect on the Quadrature Decoder 2.

 

 

 

 

(write-only)

1

Reset Quadrature Decoder 2 to 0x00 without causing an interrupt.

 

 

 

 

3

0

Quadrature Decoder 1 did not increment from 0xFF.

 

 

 

 

(read-only)

1

Quadrature Decoder 1 incremented from 0xFF to 0x00. This bit is cleared by a

read of this register.

 

 

 

 

 

 

 

 

 

 

2

0

Quadrature Decoder 1 did not decrement from 0x00.

 

 

 

 

(read-only)

1

Quadrature Decoder 1 decremented from 0x00 to 0xFF. This bit is cleared by a

read of this register.

 

 

 

 

 

 

 

 

 

 

 

1

 

This bit always reads as zero.

 

 

 

 

 

 

0

0

No effect on the Quadrature Decoder 1.

 

 

 

 

(write-only)

1

Reset Quadrature Decoder 1 to 0x00 without causing an interrupt.

 

 

 

 

 

112

Rabbit 3000 Microprocessor

Page 121
Image 121
Jameco Electronics 2000, 3000 manual Quadrature Decoder Control/Status Register, Quad Decode Control/Status Register, Qdcsr