Drives Service & Support > Product Advisories > DriveLogix and LPM20 Controllers

Ref: CPAG 2004-11-003

Functional Issue – In an MAOC Instruction, Toggling the Enable Bits While the Cam is Latched May Leave the Output Bits Latched

Problem Description

Under the following conditions, the Motion Arm Output Cam (MAOC) instruction leaves the output bit latched when the bit should unlatch.

Anytime you turn off the enable bit without considering the position of the axis, you could encounter the timing window described above and leave an output bit stuck in the latched state. For example, if your logic turns off the enable bit as an axis slows to a stop but considers only velocity (not position), the output bit could remain latched.

Affected Products:

* The “20D XXXXXXXXXXXXXA ” refers to any alpha-numeric response. . Only the first three and 17th character of the string are significant. No hyphens or slashes throughout the string.

** Note: The DriveLogix firmware version prior to 13.15 has only been made available from the Rockwell Automation web site.

This Advisory explains the functional issue and the steps being taken to rectify the situation.

Temporary Workarounds

If you want to turn off the enable bit of a Motion Arm Output Cam (MAOC) instruction, turn off the bit at a known position that is clear of the configured unlatch position.

Product Identification

To determine the firmware revision of your controller, either:

• Use the RSWho function in RSLinx software to navigate to the controller. Right-click on the controller and select Device Properties. This displays the current firmware revision of that controller.
• Use RSLogix 5000 software while online with the controller. Right-click on the controller in the Controller Organizer and select Controller Properties.

Affected ship dates are as follows:

Problem Correction

To correct this issue, update the firmware of the Drive Logix or LPM20 controller . The following firmware revisions correct the functional issues described above :

* The “20D XXXXXXXXXXXXXA” refers to any alpha-numeric response. Only the first three and 17th character of the string are significant. No hyphens or slashes throughout the string.

** Note: The DriveLogix firmware versions 13.15 ( Phase I) and 13.19 (Phase II) are available from the Rockwell Automation web site. To download a firmware update kit:

• Go to http://www.ab.com/support/abdrives/webupdate under the Powerflex 700S section

If you require any further technical assistance, contact Rockwell Automation Technical Support or your local Rockwell Automation Sales and Support office.