Rslogix 5000 Firmware 20.12 -
RSLogix 5000 firmware v20.12 is a specific maintenance and security release for the Logix5000 controller family. It is primarily recognized as a critical security update released to address vulnerabilities that could lead to Denial of Service (DoS) or unauthorized state changes. Key Specifications & Compatibility Release Date: June 2012.
Software Pairing: Controllers with firmware 20.12 are typically programmed using RSLogix 5000 v20.01 or v20.03. Note that while firmware and software major versions must match (v20), the minor versions rarely do.
Hardware Support: Specifically identified for CompactLogix L35E (Series A) and ControlLogix/GuardLogix families.
Memory: Upgrading to version 20 may increase memory requirements compared to older revisions (v11 or earlier). Major Enhancements & Security Fixes
Security Patch: Addresses a buffer overflow vulnerability that could allow attackers to alter the controller's operating state or cause a DoS. rslogix 5000 firmware 20.12
Product Resiliency: Part of Rockwell Automation's efforts to improve security practices, including tamper prevention and detection.
Resiliency Compatibility: Revision 20.12/20.012 is noted for improved interaction with later software versions like v20.04, which was designed to resolve minor revision compatibility "lock-out" issues seen in v20.03. Update Precautions
CompactLogix L35E controller Version 20.012 ... - Release Note
Part 3: How to Upgrade to RSLogix 5000 Firmware 20.12 (Step-by-Step)
Flashing a controller is a delicate operation. Doing it wrong can brick your PLC. Follow this guide meticulously. RSLogix 5000 firmware v20
12. References and primary sources
- Rockwell Automation Product Compatibility and Download Center (PCDC) — check the controller-specific firmware 20.12 release notes and compatibility listings.
- Studio 5000 / RSLogix 5000 release notes — for software-to-firmware mapping and application requirements.
- Rockwell technical support for firmware conversion, motion database updates, and controller recovery procedures.
Option B: Virtualization for Legacy Support
Many companies are choosing to freeze a specific Windows 10 Virtual Machine (VMware or Hyper-V) that contains RSLogix 5000 V20 and support for firmware 20.12. They run their modern engineering tools (Studio 5000 V35) on the host OS and spin up the VM only to service older lines.
Why v20.12 Matters
When Version 20 was first released, it had its share of growing pains. As with any major software revision, bugs were discovered. Rockwell released patches, and eventually, the firmware stabilized around the v20.12 mark.
For many integrators and maintenance teams, v20.12 became the "Gold Standard" for Version 20.
It became the default installation for:
- L73 ControlLogix Controllers: Widely used in high-performance applications.
- L33ER CompactLogix Controllers: The workhorse of the mid-tier market.
- Redundancy Systems: If you were setting up redundant chassis during this era, you were almost certainly funneled into v20.
Updating to 20.12 provided crucial bug fixes related to connection management and system overhead that plagued earlier v20.00 and v20.01 releases. If you are walking into a plant today and see a controller running v20, it is highly likely it is running v20.12.
10. Future Deprecation Warning
- Rockwell will not support v20.12 on Windows 11 (any build).
- No support for new controller hardware (e.g., 5069, 1756-L8xE).
- Recommendation: Plan migration to v32.011 or v33+ for new greenfield projects.
3. New features and functional impacts (typical for a 20.x firmware generation)
(These are representative categories; exact features depend on controller model and release notes.)
- Improved motion and synchronization features (motion database revisions, updated profiles).
- Extended instruction set or enhancements to existing instructions.
- Changes to tag data types or standard library elements.
- Diagnostics and trace improvements (better event logging, trace buffer handling).
- Enhanced redundancy or availability features for controllers that support redundant configurations.
- Security and communication stack updates (EtherNet/IP improvements, CIP message handling).
- Safety (GuardLogix) bug fixes and hardened behaviors in safety I/O handling.
Note: For precise feature lists, consult the Rockwell release notes for the specific controller catalog number and firmware 20.12 entry.