B&R Automation X20 CP1584 – Bootloader and Recovery Procedures

Applies to: B&R X20 CP1484, CP1584, CP1585, CP1586 and related X20 Compact CPUs. Based on: B&R X20 System User’s Manual, X20CP148x/158x datasheets, B&R Community forums, and field experience. This is unofficial documentation compiled from publicly available sources. Always consult the official B&R manuals at br-automation.com for authoritative procedures.

Table of Contents

1. Boot Sequence Overview
2. What Happens When the CF Card Is Corrupted or Missing
3. Bootloader Modes and Operating Mode Switch
4. LED Indications During Boot Failure
5. How to Enter Bootloader Mode on the CP1584
6. Serial Console Access
7. Firmware Recovery via Serial (B&R Service Utility)
8. TFTP Recovery Procedure
9. USB-Based Recovery
10. Runtime Utility Center for Firmware Operations
11. Automation Studio Offline Installation
12. Creating Recovery Media
13. Safe Mode and Diagnostic Mode
14. Minimum Files Needed on CF Card for Boot
15. How to Unbrick a CP1584 That Won’t Boot
16. How to Reload the Entire System from Scratch
17. Prevention and Best Practices
18. References

1. Boot Sequence Overview

When power is applied to an X20 CP1584, the following boot sequence occurs:

1. Hardware POST – The CPU performs power-on self-test. Internal flash boots the embedded bootloader firmware (stored in internal flash, not on the CF card).
2. CF Card Detection – The bootloader checks the CompactFlash slot for a valid storage card. The CF LED illuminates green if a card is detected.
3. Boot Mode Evaluation – The bootloader reads the operating mode switch position (BOOT / RUN / DIAG) and determines the startup strategy:
   • BOOT: Starts “Boot AR” – a minimal runtime environment that allows firmware installation via the online interface (Ethernet or RS-232). No user application runs.
   • RUN: Attempts to load Automation Runtime from the CF card, initialize the I/O bus, and start the user application.
   • DIAG: Boots into diagnostic mode. User RAM and User Flash contents are not initialized.
4. Runtime Load – In RUN mode, the bootloader reads the SYSTEM partition on the CF card, loads Automation Runtime, and begins I/O bus initialization.
5. Application Start – The user application (task classes) begins execution. The R/E LED turns solid green.
6. Runtime to Run – Automation Runtime transitions from RUN state to normal operation. The full X2X bus and POWERLINK networks are brought up.

The embedded bootloader is stored in internal flash on the CPU itself. It cannot be erased by CF card corruption. This is the safety net that allows recovery even when the CF card is completely destroyed.

2. What Happens When the CF Card Is Corrupted or Missing

CF Card Missing (No Card Inserted)

The CPU does not become a brick when no CF card is present. The internal bootloader always fires and provides a minimal environment for recovery.

CF Card Corrupted

Key Diagnostic: CF Card Recognition

• CF LED off – No CF card detected at all (physical seating issue, dead card).
• CF LED green – Card is detected and readable at the hardware level.
• CF LED yellow – Card is being read from or written to (normal during boot).
• CPU stays in BOOT mode after setting switch to RUN with CF card inserted – Strong indicator that CF card is not recognized, not formatted correctly (needs FAT16), or does not contain a valid operating system.

3. Bootloader Modes and Operating Mode Switch

The X20 CP1584 has a physical operating mode switch on the front panel:

Switch Positions

Important: A switch position between BOOT, RUN, and DIAG is not permitted. The switch has detents at these three positions only.

Reset Button Behavior

The reset button is located below the USB interfaces on the bottom of the CPU housing. It can be pressed with a small pointed object (e.g., paperclip).

Note: Pressing Reset does not erase the program from CF card. It stops execution and reboots.

4. LED Indications During Boot Failure

Primary CPU Status LEDs (CP1484 / CP1584 / CP1585 / CP1586)

System Stop Error Codes (S/E LED Blinking Red)

The error code is indicated by the S/E LED blinking red. The pattern consists of 4 switch-on phases, each either short (150 ms) or long (600 ms), repeated every 2 seconds.

Power Supply LEDs

Interpreting Common Boot Failure LED Patterns

5. How to Enter Bootloader Mode on the CP1584

Method 1: Operating Mode Switch (Primary)

1. Set the switch to BOOT – Slide the mode switch to the BOOT position.
2. Power cycle – Power off the X20 system, wait 30 seconds, power back on.
3. The CPU will start in BOOT mode. R/E LED = red, RDY/F LED = yellow.
4. In BOOT mode, the embedded Boot AR runtime initializes the Ethernet and RS-232 interfaces, allowing you to connect for firmware download.

Method 2: Missing/Invalid CF Card with Switch in RUN

1. Remove the CF card (or leave a corrupted card in place).
2. Set switch to RUN.
3. Power cycle – the CPU will fall back to BOOT mode since no valid runtime is found on the CF card.
4. This gives you the same recovery environment as Method 1.

Method 3: Reset Button

1. With the CPU running, press the reset button for less than 2 seconds to trigger a warm restart.
2. Within 2 seconds of the restart, press and hold the reset button for more than 2 seconds (while R/E LED is red indicating reboot).
3. This can force the CPU into diagnostic/reset mode, which also allows recovery operations.

Method 4: Software Stop Target

1. Connect to the CPU via Automation Studio (Ethernet or serial).
2. Use Online > Stop Target to halt the application.
3. The CPU enters SERVICE mode. From here you can perform diagnostics and recovery.

6. Serial Console Access

Serial Port (IF1) Specifications

Connection Procedure

1. Wire RS-232 correctly:

   PLC RX (Pin 5)  <--->  PC TX (Pin 3)
   PLC TX (Pin 3)  <--->  PC RX (Pin 2)
   PLC GND (Pin 7) <--->  PC GND (Pin 5)
   

   Double-check the pin assignments on your specific terminal block. The X20TB12 pin numbering follows B&R conventions shown in the datasheet.

2. Configure terminal emulation software (e.g., PuTTY, Tera Term, HyperTerminal):

   • Baud: 57600
   • Parity: Even
   • Data: 8 bit
   • Stop: 1
   • Flow: None

3. Open the serial connection. If using PVI Transfer Tool or Automation Studio, configure these same settings in the online connection settings.

4. The RS-232 LED on the power supply module will light yellow when data is being transmitted or received.

RS-232 Serial Interface — Important Notes

• The RS-232 interface is not electrically isolated from the PLC. Use caution with ground loops.
• In BOOT mode, the RS-232 interface is initialized and ready for communication – this is the fallback path when Ethernet is unavailable.
• If the default 57600 baud doesn’t work, try 9600 or 115200. The baud rate can be configured in the project’s serial interface settings (IF1) in Automation Studio. If someone changed it, you may need to cycle through baud rates.
• USB interfaces (IF4/IF5) on the X20 CPUs are USB 1.1 and are only for B&R-approved devices (dongles, approved USB storage). They cannot be used for serial communication with a PC.

7. Firmware Recovery via Serial (B&R Service Utility)

The B&R Service Utility is a firmware installation tool that can set the embedded firmware of a B&R PLC via serial connection. It is typically provided by B&R service and is not part of the standard Automation Studio distribution.

When Serial Recovery Is Needed

• The CF card is completely corrupted or missing.
• You have no way to connect via Ethernet (no IP address, unknown subnet, etc.).
• The embedded firmware itself needs to be reflashed (rare – this is the lowest-level firmware in the CPU’s internal flash).

Serial Recovery Procedure

1. Obtain the B&R Service Utility and the appropriate firmware files from B&R support.
2. Connect the RS-232 serial cable between your PC and the CPU’s IF1 terminal block.
3. Set the CPU mode switch to BOOT.
4. Power on the CPU.
5. Launch the B&R Service Utility on your PC.
6. Configure the serial port settings (57600, 8, E, 1).
7. Select the firmware file(s) appropriate for your CPU model.
8. Follow the utility’s prompts to begin the firmware transfer.
9. After completion, the CPU should be able to boot from a properly prepared CF card.

Note: The B&R Service Utility and its firmware files are generally only available through B&R service/support channels, not through public download. Contact your local B&R support office if you need this tool.

8. TFTP Recovery Procedure

B&R X20 CPUs with the embedded Boot AR runtime in BOOT mode support firmware installation over the network. While B&R does not publicly document a “TFTP boot” command set in the same way consumer routers do, the recovery process uses the standard B&R online transfer mechanism which internally uses the B&R protocol (not raw TFTP).

Network-Based Firmware Installation (BOOT Mode)

This is the standard network recovery path:

1. Prepare the CPU:

   • Set mode switch to BOOT.
   • Power on the CPU. Wait for BOOT mode (R/E red, RDY/F yellow).

2. Establish Network Connectivity:

   • Connect an Ethernet cable from the CPU’s IF2 (Ethernet port) to your PC or network switch.
   • The CPU in BOOT mode may default to IP 0.0.0.0 until configured, or may have a previously configured IP.
   • Set your PC’s Ethernet interface to the same subnet (e.g., 192.168.0.10).
   • Optionally set the CPU’s IP via SNMP in Automation Studio’s Browse window, or use a DHCP server on the network.

3. Browse for the Target:

   • Open Automation Studio.
   • Go to Online > Settings.
   • Click Browse targets – the CPU should appear in the list.
   • Right-click the CPU and select Set IP parameters if needed.

4. Transfer Automation Runtime:

   • In Automation Studio, go to Project > Services > Transfer Automation Runtime.
   • Follow the wizard to select the target and transfer the runtime to the CF card.
   • This formats the SYSTEM partition, installs Automation Runtime, and prepares the card.

5. Transfer Your Application:

   • After Automation Runtime is installed, transfer your application project:
   • Project > Transfer > Total (or configure individual transfer types).

What Happens Internally

The Boot AR runtime in the CPU listens on the configured network interface. Automation Studio connects using the B&R PVI (Process Visualization Interface) protocol, which internally manages file transfer. This is not a raw TFTP session but rather a proprietary B&R protocol running over TCP/IP.

9. USB-Based Recovery

X20 CPU USB Limitations

The USB interfaces (IF4 and IF5) on X20 CPUs are USB 1.1 host ports designed only for B&R-approved devices:

• B&R dongles (license keys)
• B&R-approved USB floppy drives
• B&R-approved USB mass storage (DiskOnKey)

The USB ports cannot be used for:

• Direct PC-to-PLC communication (online connection)
• Serial-over-USB communication
• Keyboard/mouse

USB Installation for Panel Controllers

For B&R Panel controllers with built-in HMI (e.g., PowerPanel, Panel PCs like the 4PPC70 series), USB installation is a supported recovery method:

1. Format a USB stick as FAT32.
2. In Automation Studio, go to Project > Project Installation > Offline Installation.
3. Select USB as the target and generate the installation package.
4. Insert the USB stick into the controller’s USB port.
5. Set the mode switch to BOOT (press reset < 2s, then hold > 2s within 2 seconds).
6. The installation should automatically execute.

Note: For the X20 CP1584 CPU (no built-in HMI display), USB installation may not be directly applicable in the same way. The primary recovery paths for X20 CPUs are: CF card (offline install to CF card reader), Ethernet online transfer, and RS-232 serial transfer.

USB CF Card Reader Method (Recommended for X20 CPUs)

Since X20 CPUs use removable CompactFlash, the standard “USB recovery” is:

1. Remove the CF card from the CPU.
2. Connect the CF card to your PC using a USB CF card reader.
3. Use Automation Studio’s Offline Installation to write the CF card.
4. Reinsert the CF card into the CPU and power on.

This is covered in detail in Section 11.

10. Runtime Utility Center for Firmware Operations

Overview

Runtime Utility Center (RUC) is part of the PVI Development Setup package, available for free download from B&R’s website under Software > Automation Runtime. It provides tools for creating, backing up, and restoring CompactFlash cards without needing an active PLC connection.

Key Functions

Creating a CF Card with RUC

1. Download and install PVI Development Setup from br-automation.com.
2. Launch Runtime Utility Center from the Start menu.
3. Insert a blank CF card into a USB card reader connected to your PC.
4. Press F9 or use the menu to open Create CompactFlash.
5. Click Select source and browse to your configuration/backup files.
6. Select the CF card drive letter from the list.
7. Click Create to generate the CF card.
8. Wait for completion. The card will be formatted and populated with the required files.

Backing Up a CF Card

1. Insert the source CF card into a USB card reader.
2. Open Runtime Utility Center.
3. Navigate to CF Card Tools.
4. Select Create Image to save a backup (.img file) to your PC.
5. Save with a descriptive name (e.g., CP1584_backup_2026-07-10.img).

Restoring a CF Card from Backup

1. Insert a blank (or same-capacity/larger) CF card into the card reader.
2. Open Runtime Utility Center.
3. Navigate to CF Card Tools.
4. Select Restore Image.
5. Browse to your .img backup file.
6. Confirm the restore operation.

Backup File Formats

RUC creates backup files named zp.1, zp.2, zp.3 etc. These are incremental sector images of the CF card. To restore, select the latest zp file.

CF Card Backup and Restore — Important Notes

• Always use a quality card reader. Many CF card issues during backup/restore are caused by cheap or faulty readers.
• For X20 CPUs, use B&R-approved CF cards (SLC type preferred): 5CFCRD series.
• The CF card must have a valid FAT16 partition for the CPU to recognize it.
• RUC may show “partitions = 0” if the card has no valid partition table or is in RAW format.

11. Automation Studio Offline Installation

The Offline Installation is the most common method for preparing a CF card for an X20 CPU. It does not require the CPU to be connected at all – you write the card on your PC.

Offline Installation Procedure

1. Open your project in Automation Studio.
2. Go to Project > Project Installation > Offline Installation (in some versions: Tools > Create CompactFlash or the wizard).
3. Select the target:
   • CompactFlash card – requires a CF card reader connected to your PC.
   • USB stick – for controllers that support USB boot (Panel PCs).
4. Configure the installation:
   • Select the Automation Runtime version to install.
   • Choose whether to create a USER partition for user files.
   • Select any additional files to include.
5. Click Create or Install.
6. Automation Studio will:
   • Format/prepare the CF card with correct partitions (SYSTEM partition formatted FAT16, then converted to the B&R raw filesystem for speed).
   • Install the Automation Runtime operating system.
   • Copy the application project files.
   • Set up the transfer folder with installation instructions.
7. Insert the CF card into the CPU.
8. Power on with the mode switch in RUN.
9. On first boot, the CPU performs the initial installation:
   • The transfer folder contents are unpacked.
   • SYSTEM partition is finalized.
   • The CPU will reboot one or more times.
   • After several minutes, it should enter RUN mode (R/E green solid).

CF Card Preparation Requirements

Before offline installation:

1. Windows Disk Management: The CF card should have its partitions removed (show as “Unallocated”) or have a single primary FAT16/FAT32 partition.
2. If the card shows as RAW: Delete the volume first in Disk Management (right-click > Delete Volume), then create a new primary partition.
3. Run Automation Studio as Administrator: This ensures partition-level access to the CF card.

Troubleshooting Offline Installation

12. Creating Recovery Media

What You Need

Creating a Recovery CF Card (Full Method)

1. Obtain a new or known-good CF card of appropriate capacity.

2. Connect the CF card to your PC via card reader.

3. In Windows Disk Management, ensure the card has a clean partition layout:

   diskpart
   select disk X        (where X is the CF card disk number)
   clean
   create partition primary
   format fs=fat16
   assign letter=Z
   

   WARNING: Double-check the disk number. clean destroys all data on the selected disk.

4. Open Automation Studio and load your project.

5. Go to Project > Project Installation > Offline Installation.

6. Select the CF card as target.

7. Enable:

   • Automation Runtime installation
   • User partition creation (if needed)
   • Any user files to pre-populate

8. Generate the installation.

9. Label the CF card with the project name, date, and AR version.

10. Store in a safe location as your recovery media.

Creating a Recovery Image (Backup Method)

1. Take the working CF card from a running system.
2. Back up using Runtime Utility Center Create Image.
3. Save the .img file to your PC and external backup storage.
4. To restore: Use RUC Restore Image to write to a new CF card.

Disk Image Method (Alternative)

If RUC is unavailable, use sector-level imaging:

1. Backup: Use a disk imaging tool (e.g., dd on Linux, Clonezilla, or Win32DiskImager) to create a raw image of the entire CF card:

   dd if=/dev/sdX of=cp1584_backup.img bs=4M status=progress
   

2. Restore: Write the image back:

   dd if=cp1584_backup.img of=/dev/sdX bs=4M status=progress
   

Warning: This creates a byte-for-byte clone. The destination card must be the same capacity or larger, and may need manual partition resizing if larger.

13. Safe Mode and Diagnostic Mode

Diagnostic Mode

Diagnostic mode is entered when:

• The mode switch is set to DIAG.
• The reset button is held for longer than 5 seconds (on some controller types).

In Diagnostic mode:

• Program sections in User RAM and User FlashPROM are not initialized.
• I/O modules are initialized and the bus system is checked.
• You can connect via Automation Studio to run diagnostics, inspect I/O states, and read the logbook.
• After leaving DIAG mode (power cycle or switch change), the CPU always performs a warm restart.

Service Mode

Service mode is entered when:

• The reset button is pressed for 2-5 seconds.
• The “Stop Target” command is sent from Automation Studio.
• A critical runtime error occurs (cycle time violation, page fault, divide by zero, etc.).

In Service mode:

• No task classes are running. The application program is halted.
• Outputs are set to zero (or their configured safe state).
• You can connect via Automation Studio to diagnose the fault.
• Check the Logger (Open > Logger in Automation Studio) for error codes.
• The Diagnostic buffer contains the fault information.

System Diagnostics Manager (SDM)

When Automation Runtime is running (or in SERVICE mode), the CPU runs a built-in web server for diagnostics:

1. Connect your PC to the same network as the CPU.
2. Open a web browser and navigate to http://<CPU_IP>/sdm (default: http://10.0.0.220/sdm for some configurations).
3. The SDM web interface shows:
   • Hardware status
   • Software components and versions
   • Error and event log
   • I/O module status
   • Network diagnostics

Note: SDM may be disabled in some project configurations. Check the project’s Ethernet settings if you cannot reach the SDM page.

Safe Commissioning

B&R provides a SafeCommissioning mechanism for initial commissioning and recovery. This allows a controlled initial startup where the system can be verified before full operation:

• The SafeCommissioning configuration is stored in the SYSTEM partition.
• A backup of the modified SafeCommissioning file should be maintained separately from the SYSTEM partition.

Safety-Relevant Boot Behavior

• The CPU does not silently ignore faults during boot.
• Any unrecoverable error during boot causes the CPU to enter SERVICE or BOOT mode, not RUN mode.
• The logbook records all boot errors with timestamps and error codes.

14. Minimum Files Needed on CF Card for Boot

CF Card Partition Structure

A properly formatted B&R X20 CF card has (at minimum) a SYSTEM partition containing the Automation Runtime:

[SYSTEM Partition - B&R Raw Filesystem]
  |-- Automation Runtime files
  |-- System configuration
  |-- Transfer folder (used during initial installation)
  |-- Logger data (RPSHD folder)
  |-- ...

[USER Partition - FAT16/FAT32] (optional)
  |-- User application data
  |-- Configuration files
  |-- Backups
  |-- ...

Minimum Requirements for Boot to RUN

1. Valid partition table – At least one partition must exist.
2. SYSTEM partition – Formatted with the B&R raw filesystem (created by Automation Studio during offline install).
3. Automation Runtime files – The operating system components:
   • B&R Automation Runtime kernel
   • Required system libraries and drivers
   • Hardware support packages (for the specific CPU model)
4. System configuration – Network settings, I/O configuration, task class definitions.
5. Application project – At minimum, a project with configured task classes (even if empty tasks). Without any application, the CPU may enter SERVICE mode rather than RUN mode.

What the Boot AR Internal Firmware Provides

Even with no CF card, the CPU’s internal flash contains enough firmware to:

• Initialize the Ethernet interface (limited functionality)
• Initialize the RS-232 serial interface
• Respond to network browsing from Automation Studio
• Enter BOOT mode for firmware download
• Display basic boot status via LEDs and serial console

CF Card Corruption Recovery: Decision Tree

When a CF card is suspected to be corrupted (PLC won’t boot to RUN, or keeps entering SERVICE mode), follow this decision tree:

PLC won't boot to RUN
|
|-- Are LEDs lit on power-up?
|   |-- NO LEDs at all → Check 24V power supply to CPU
|   |-- Only PWR LED → Internal firmware OK, CF card not being read
|   |   |-- Remove CF card → Clean contacts with isopropyl alcohol → reinsert
|   |   |-- Try known-good CF card → If boots → original card is faulty
|   |   `-- If still no boot with known-good card → CPU hardware fault
|   |
|   |-- RDY/F flashing rapidly → CF card is being read but system files are corrupt
|   |   |-- Check arlogsys.log via FTP (anonymous, C: partition may be partially readable)
|   |   |-- Image the CF card with dd for forensic analysis before any recovery attempt
|   |   |-- Restore from backup image → if works, card had logical corruption
|   |   `-- If backup fails → create new CF card via AS Offline Installation
|   |
|   |-- RDY/F solid red → SERVICE mode
|       |-- Connect via AS and check Logger → identifies the specific error
|       |-- If Logger shows "file system error" → CF card filesystem corruption
|       |-- If Logger shows cycle time violation (144/145) → application bug, not CF issue
|       `-- If Logger shows no error → may be retentive data corruption or battery issue
|
`-- CPU enters BOOT mode (RDY/F alternating red/green)
    |-- Mode switch is in BOOT position → move to RUN
    |-- CF card has only transfer folder (not yet installed) → normal for first-time install
    `-- CF card is blank or unrecognizable → need fresh Offline Installation

Community-sourced tip (B&R Community Forum): If the files on the CF card are corrupt, the PLC will boot into Diagnostic mode and Automation Runtime won’t start. You can still access the CF card contents via FTP (anonymous, read-only to C: partition) to pull the arlogsys.log and diagnose what went wrong. On some AR versions, a partial boot allows limited SDM access even with corrupted files — try browsing to http://<PLC_IP>/sdm before removing the CF card.

CF Card Write Endurance and Failure Patterns

B&R-branded SLC (Single-Level Cell) CF cards have significantly higher write endurance than consumer MLC cards. However, they still have finite lifespan:

Failure progression pattern for B&R SLC cards:

1. Phase 1: Increased boot time (filesystem wear leveling overhead)
2. Phase 2: Occasional file write errors (logged in arlogsys.log)
3. Phase 3: Files becoming unreadable (0-byte files, corrupted data)
4. Phase 4: Complete card failure — CPU cannot read any partition

The CP1584 bootloader is designed to handle Phase 1-3 gracefully:

• In Phase 1-2, the PLC boots normally but may show slower startup
• In Phase 3, the PLC may enter Diagnostic mode or fall back to BOOT mode
• In Phase 4, the CPU enters BOOT mode and the system LED shows a solid pattern
• At this point the bootloader still accepts firmware via serial/TFTP, so the CPU itself is not bricked — only the CF card is dead

Detection: Monitor arlogsys.log for filesystem-related errors (error codes related to file I/O, bad sectors). If you see increasing filesystem errors over weeks/months, the CF card is approaching end of life. Replace it proactively — do not wait for complete failure.

Recommended Minimum CF Card Size

Always use B&R SLC CF cards for reliability:

• 5CFCRD.0512-06 (512 MB)
• 5CFCRD.1024-06 (1 GB)
• 5CFCRD.2048-06 (2 GB)
• 5CFCRD.4096-06 (4 GB)

15. How to Unbrick a CP1584 That Won’t Boot

Diagnosis Flowchart

Power on CPU
  |
  +-- No LEDs at all?
  |     --> Check power supply (24VDC), wiring, fuse.
  |
  +-- CF LED off?
  |     --> Re-seat CF card. Try a known-good CF card. 
  |     --> If still off, possible CF slot hardware failure.
  |
  +-- Stuck in BOOT mode (R/E red, RDY/F yellow)?
  |     --> CF card issue. Proceed to "CF Card Recovery" below.
  |
  +-- Stuck in SERVICE mode (R/E red)?
  |     --> Application issue. Connect via AS, check Logger.
  |
  +-- S/E red blinking with error code?
  |     --> Hardware error. May need CPU replacement.
  |
  +-- DC LED red?
        --> Battery empty. Replace CR2477N battery.

Step-by-Step Unbrick Procedure

Phase 1: Quick Checks

1. Check all LED states and document them before doing anything.
2. Full power cycle: Power off, wait 30 seconds, power on.
3. Check backup battery: Replace if DC LED is red. Use only Renata CR2477N.
4. Re-seat the CF card: Remove it, inspect for damage/corrosion, reinsert firmly.
5. Try a known-good CF card: If you have a spare, try it.

Phase 2: CF Card Recovery

If the CF card is suspected corrupted:

Option A: Recreate from Automation Studio (Preferred)

1. Remove the CF card and connect it to your PC via card reader.
2. Back up the card if possible (RUC Create Image or file copy).
3. In Windows Disk Management, delete all partitions and create a single FAT16 primary partition.
4. Use Automation Studio Offline Installation to write the CF card.
5. Reinsert into CPU, power on with switch in RUN.

Option B: Total CF Card Replacement

1. Obtain a new B&R CF card.
2. Connect to PC via card reader.
3. Format as FAT16 primary partition (via Disk Management or diskpart).
4. Use Automation Studio Offline Installation.
5. Insert and power on.

Option C: Restore from Backup Image

1. If you have a backup .img or zp files, use RUC Restore Image.
2. Write to a new CF card.
3. Insert and power on.

Phase 3: Network Recovery (No Valid CF Card)

If you cannot prepare a CF card:

1. Set mode switch to BOOT.
2. Connect Ethernet cable directly from CPU to your PC.
3. Set your PC’s IP to the same expected subnet.
4. Open Automation Studio > Online > Settings > Browse.
5. Find the CPU in the list (it appears in BOOT mode).
6. Right-click > Set IP parameters if needed.
7. Perform Transfer Automation Runtime (Project > Services > Transfer Automation Runtime).
8. After AR is transferred to the CF card, perform Total Transfer of your project.

Phase 4: Serial Recovery (No Network)

If Ethernet is unavailable:

1. Connect RS-232 cable from PC to CPU IF1 terminal block.
2. Configure terminal: 57600, 8, E, 1, no flow control.
3. Set mode switch to BOOT.
4. Power on.
5. In Automation Studio, configure a serial connection to the CPU.
6. Transfer Automation Runtime and project via serial.
7. Serial transfers are slow but reliable.

Phase 5: Hardware Failure

If none of the above works:

1. Module swap test: Remove the CPU and test it in a different X20 rack/slot with a known-good power supply and CF card.
2. Check for bent pins or corrosion on the backplane connectors.
3. If S/E LED shows a RAM or Hardware error code (see Section 4), the CPU may be defective.
4. Contact B&R support for RMA/repair.

Special Case: APC Panels (Automation PC)

For B&R Automation PCs (APC3100, APC910, etc.) that use CFast instead of CF:

1. Check BIOS settings: Ensure “Realtime Environment” is enabled, “Hypervisor Environment” is disabled.
2. Update BIOS and MTCX to the latest versions.
3. Disable “Quick Boot” and “Quiet Boot” in BIOS to see boot messages.
4. CFast cards can be prepared the same way as CF cards via Offline Installation.
5. If the screen shows BIOS-level messages about SATA mass storage, the CFast card or BIOS may be the issue.

16. How to Reload the Entire System from Scratch

This procedure assumes you want to start from a completely blank state.

Prerequisites

• PC with Automation Studio installed
• CF card reader
• New or wiped CF card
• Your project file (.apj)
• Automation Runtime installer package (matching your project’s AR version)

Step-by-Step

1. Prepare the CF Card

diskpart
list disk
select disk X       (your CF card -- double-check!)
clean
create partition primary
format fs=fat16
assign
exit

2. Create the Installation Media

1. Open Automation Studio with your project loaded.
2. Project > Project Installation > Offline Installation.
3. Target: The CF card drive.
4. Options:
   • Install Automation Runtime: Yes
   • Create USER partition: Yes (if you need persistent user data)
   • Include user files: Point to any configuration files to pre-load
   • SYSTEM partition size: Leave default (minimum ~488 MB)
5. Click Create/Install.
6. Wait for completion.

3. Install in the CPU

1. Power off the X20 system.
2. Insert the prepared CF card into the CPU.
3. Set mode switch to RUN.
4. Power on.
5. The CPU will:
   • Boot from the CF card
   • Perform initial installation (unpack transfer folder)
   • Reboot one or more times
   • Transition through PREOPERATIONAL to RUN
6. Watch the LEDs:
   • R/E green blinking: Initializing (wait)
   • R/E green solid: Application running (success)
   • If stuck red/yellow: Something went wrong – check the CF card or use the Logger

4. Verify

1. Connect via Automation Studio (Ethernet).
2. Go to Online > Settings and verify the CPU appears and is in RUN mode.
3. Check the Logger for any warnings or errors.
4. Verify all I/O modules are detected and operating.
5. Verify POWERLINK/Ethernet communication.

5. Configure Network (if needed)

If you need to change the IP address after installation:

1. Open the project in Automation Studio.
2. Navigate to the CPU’s Ethernet configuration.
3. Set the desired IP address, subnet mask, and gateway.
4. Enable SNMP for future diagnostics.
5. Transfer the updated configuration (Project > Transfer > Configuration or Total).

17. Prevention and Best Practices

Backup Strategy

CF Card Handling

• Never remove the CF card while the CPU is powered on.
• Use only B&R SLC CF cards (5CFCRD series) for industrial environments.
• Store spare CF cards in anti-static packaging.
• Replace CF cards every 3-5 years in harsh industrial environments (SLC cards have limited write cycles).

Battery Maintenance

• Replace the backup battery (CR2477N) every 4 years or whenever the DC LED shows red.
• Only use Renata CR2477N batteries. Other brands may present fire/explosion hazards.
• Replace within 1 minute if power is off to prevent data loss.
• The battery buffers: remanent variables, user RAM, system RAM, and the real-time clock.

Firmware and Software

• Keep Automation Studio and PVI updated to the latest stable version.
• Keep Automation Runtime at the version specified by your project.
• Test firmware upgrades on a spare CPU before deploying to production.
• Use B&R’s Update tool for firmware upgrades to ensure compatibility.

Power Quality

• Ensure proper 24VDC power conditioning.
• Verify power supply can handle the full load of the X20 system.
• Use slow-blow fuses (max 10A) as specified.
• Protect against power surges and voltage sags.

Network Configuration

• Always enable SNMP in the project for diagnostics.
• Document all IP addresses and network settings.
• Keep a record of the CPU’s station address (hex switches).
• Ensure your PC can reach the CPU’s default IP before making changes.

Key Findings

• The CP1584 cannot be bricked by CF card damage alone — the embedded bootloader in internal flash always provides a minimal recovery environment (Boot AR) with Ethernet and RS-232 access, even with no CF card inserted.
• Serial console defaults to 57600 baud, 8 data bits, even parity, 1 stop bit (8,E,1) on the IF1 RS-232 terminal block — this is your fallback path when Ethernet is unavailable, and the baud rate may have been changed from default by a prior configuration.
• BOOT mode vs. SERVICE mode are fundamentally different — BOOT mode means Automation Runtime failed to load from the CF card (firmware/OS issue); SERVICE mode means AR loaded successfully but the user application crashed or was stopped (application issue). The diagnostic approach for each is completely different.
• The operating mode switch (BOOT/RUN/DIAG) is the primary recovery control — set to BOOT, power cycle, and the CPU enters the minimal Boot AR runtime ready for firmware transfer via Ethernet or serial.
• CF card corruption is the most common failure cause — always re-seat the card first, then try a known-good spare before escalating to firmware reflash or hardware replacement. The CF LED being off immediately indicates a physical detection problem.
• Three recovery paths exist in priority order: (1) prepare a new CF card via Automation Studio Offline Installation, (2) network recovery via BOOT mode and Transfer Automation Runtime, (3) serial recovery at 57600 baud as last resort.
• USB ports on X20 CPUs cannot be used for PC communication or serial console — they are USB 1.1 host ports restricted to B&R-approved devices only; the serial-to-USB approach requires the RS-232 terminal block, not USB.
• Always image a CF card before any recovery attempt using Runtime Utility Center (Create Image) or sector-level dd — the original card may contain the only copy of the safety configuration and application parameters.

18. Cross-References

19. References

Official B&R Documentation

Community and Third-Party References

Cross-References

Revision History