Transducer Type - Bits 12-15
|
15 |
14 |
13 |
12 |
Transducer Type |
|
0 |
0 |
0 |
0 |
Start/Stop (S-S) |
|
x |
x |
x |
x |
Pulse-width Modulated (PWM) |
Setting any of these four bits to non-zero (as described below in the Recirculation Count section) will result in the transducer being treated as pulse-width modulated.
Recirculation Count - Bits 12-15
If the transducer is pulse-width modulated (PWM or gated), these bits select number of recirculations. The following values are available:
|
15 |
14 |
13 |
12 |
Recirculations |
|
0 |
0 |
0 |
1 |
1 |
|
0 |
0 |
1 |
0 |
2 |
|
0 |
0 |
1 |
1 |
3 |
|
0 |
1 |
0 |
0 |
4 |
|
0 |
1 |
0 |
1 |
5 |
|
0 |
1 |
1 |
0 |
6 |
|
0 |
1 |
1 |
1 |
7 |
|
1 |
0 |
0 |
0 |
8 |
|
1 |
0 |
0 |
1 |
9 |
|
1 |
0 |
1 |
0 |
10 |
|
1 |
0 |
1 |
1 |
11 |
|
1 |
1 |
0 |
0 |
12 |
|
1 |
1 |
0 |
1 |
13 |
|
1 |
1 |
1 |
0 |
14 |
|
1 |
1 |
1 |
1 |
15 |
When a transducer is set for multiple recirculations, there is a small time delay between those recirculations. During this time the counter on the motion controller continues to count, resulting in "extra" counts which are added to the Transducer Counts. These extra counts use some of the 65535 maximum counts that are available, reducing the maximum stroke the module can control to 65535 minus the "extra" counts. To correct for this effect the module calculates the "extra" counts based on the number of transducer recirculations and subtracts them from the transducer count. If the value of these bits and the transducer recirculations agree, the transducer count will be slightly positive when the transducer is at its minimum position.
In some cases it may be desirable to set bits 12-15 to a value greater than the number of recirculations to subtract additional counts, but if the value selected is too large it is possible to get a position underflow condition. If this happens, the Position Overflow status bit will be set and the Actual Position will be equal to the Offset parameter.
Rising-/Falling-Edge Selection - Bit 7
Use this bit to select the edge of a start/stop transducer’s waveform to be used. Notice that this bit is ignored if a PWM transducer is selected as described above. Most transducers use rising edges, but some transducers manufactured by Balluff are known to use falling edges.
|
Bit 7 |
Transducer Edge |
|
0 |
Rising (default) |
|
1 |
Falling |
Copyright (c) 1997-2015 by Delta Computer Systems, Inc.