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Permission Denied Error when communicating with Allen-Bradley ControlLogix (Firmware 20.19 or 20.57)
The TOP Server Allen-Bradley ControlLogix Ethernet driver cannot communicate with controllers running firmware 20.19 or 20.57 when the Protocol Mode in Device Properties > Logix Options is set to Logical Blocking or Logical Non-Blocking
When the server attempts to update tags the controller responds with a CIP 0x0F Permission Denied error.
This is the result of issues in these specific versions of Rockwell firmware. There is nothing our developers could do to work around the firmware bugs, resulting in the options below as solutions.
Solutions:
- Use Symbolic Protocol Mode - Using Symbolic Protocol Mode is the easiest resolution if applicable. Symbolic protocol is best for applications where the tag count is not huge (<500). Refer to the Performance optimization section of the Allen Bradley ControlLogix Ethernet driver help file for guidance.
- Upgrade the Device Firmware - This is best path forward if the application requires use of Logical Protocol Mode for performance optimization. In this case, update the controller to firmware V21 or higher. Device firmware compatibility and update instructions can be found on the Rockwell Automation Technical Support site.
- Downgrade the Device Firmware - This is best path forward if the application requires use of Logical Protocol Mode for performance optimization, but the device does not support a firmware revision beyond V20. In this case, update the controller to firmware V20.18 (20.55 for redundant CPU) or lower. Device firmware compatibility and update instructions can be found on the Rockwell Automation Technical Support site.