Installing, Connecting and Using the Encoder Mod-

The actual formula is as follows:

Distance = (Destination - Counter value) / Divider

Where: divider is a configurable parameter of value 1, 2, 4, 8, 16, 32, 64 or 127

If computed distance is less than -127, then reported distance is -127

If computed distance is larger than +127, then reported distance is +127

Destination= 50,050

Counter= 50,000

distance

at divider

50

1

25

2

12

4

6

8

3

16

1

32

0

64

0

128

FIGURE 46. Small distance computation example

Destination= 50,000

Counter= 45,000

distance

at divider

127

1

127

2

127

4

127

8

127

16

127

32

78

64

39

128

FIGURE 47. Large distance computation example

Important Notice

Encoders do not report an absolute position value but a count that is relative to the point where the motor shaft was at power up. It is typically necessary to have the motors moved to a “home” position and reset the counters at that reference point.

RS232 Communication with the Encoder Module

The contains its own Microcontroller and firmware in Flash. When present, it responds to a large set of dedicated commands and queries via the controller’s serial port. See “RS232 Encoder Command Set” on page 145.

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AX1500 Motor Controller User’s Manual

Version 1.9b. June 1, 2007

Page 78
Image 78
RoboteQ AX2550, AX1500 RS232 Communication with the Encoder Module, Distance = Destination Counter value / Divider