Rockwell Automation 1771-QA Stepper Positioning Assembly User Manual User Manual
Page 41
3–19
Programming and Operation
Publication 1771-UM002A–EN–P – May 2000
Move Data
Move data is contained in the remaining five words of the move
block (Figure 3.13). Values are entered in BCD. Those shown in
Figure 3.13 are the maximum allowable values. Undefined bits (bits
14-17) in the words specifying the ramp, decel and position must be
filled with zeros.
Figure 3.13
Move Block
17
10 07
00
Data Table
9
9
9
9
9
9
9
9
9
9
0
0
0
0
10525
9
9
9
0
0
0
0
9
9
9
0
0
0
0
0
0
0
0
Single Move Control Word
0 – 9.99 Seconds
0 – 9,999 x 1
0 – 2,000 x 10
0 – 9.99 seconds
0 – 999,999 Pulses
SMCW
Ramp
Rate
Decel
MS Position
LS Position
Pulses per
second
Ramp Time
The ramp value is the number of seconds the positioning assembly
will take to reach a (new) final rate. In the continuous mode, the
final rate can be greater than or less than the starting rate. Ramp
time can be any value between 0 and 9.99 seconds. Refer to section
titled “Application Considerations.”
Final Rate
The final rate value determines the constant speed of the move. The
rate can be any value between 0 and 9,999 pulses per second or in
increments of 10 pulses per second between 0 and 20,000 pulses per
second. Refer to section titled “Application Considerations.”
Important:
When the rate multiplier bit (bit 01) of the single move
control word is set, the resulting rate will be equal to the
programmed rate value times ten.
Decel
The deceleration value is the number of seconds the positioning
assembly will take to decelerate to zero pulses per second. It should
not be confused with a ramp to a lower final rate other than zero.
The decel is an active part of the move profile in the single step and
independent modes.