Siemens SIMATIC 505 User Manual

Programming

Series 505 High Speed Counter

 and Encoder Module User

’s Manual

Reset Command. Both channels have a Reset Command bit. A transition
from 0 (off) to 1 (on) of the Reset Command acts as a one-shot (providing a
momentary reset of the channel), setting the count to 0. Even though the
bit remains 1, counting resumes.

Inhibit Command. Both channels have an Inhibit Command bit. When this
bit is set to 1, the channel stops counting.

NOTE: When in the pulse counter mode, if the A or B input is in a
different state at the beginning and end of an inhibit signal, the count
will change according to the normal counting logic. If both A and B
inputs are in different states, the change may be as much as two
counts.

Output Level. The output level bit specifies when the outputs for each
channel turn on.

Setting the output level bit to 0 turns the output on when the current
count is greater than or equal to the preset. If the current count is less
than the preset, the output is off.

Setting the output level bit to 1 turns the output on when the current
count is less than the preset. If the current count is greater than or
equal to the preset, the output is off.

Words WY5 through WY8 specifies preset values for each channel.

You can specify any value between 0 and 65,535.

 WY5 specifies the value for Preset 1, Channel 1.

 WY6 specifies the value for Preset 2, Channel 1.

 WY7 specifies the value for Preset 1, Channel 2.

 WY8 specifies the value for Preset 2, Channel 2.

In each scan, the controller reads the module WX words before updating

the WY words. For example, during a scan when the controller resets the
module, the WX word(s) contain counter values existing prior to the reset.