README

BIOS Splitter/Merger Tool

Overview

A Lazarus/Free Pascal tool to split and merge binary files using either odd/even byte separation or first half/second half division. Useful for backup, modification, or transferring large files in parts.

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Features

• Split files into odd/even bytes or first half/second half
• Simple GUI for selecting files and toggling split modes
• Logs all actions for easy tracking

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Requirements

• For compiling Lazarus 4 (or Free Pascal with LCL)
• Tested on Windows

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Usage

1. Select a File to Split

• Click "Select File to SPLIT" and choose the file you want to split
• The selected file path will appear in the log

2. Choose Split Mode

Option	Output Files	Use Case
Odd/Even Split	_odd.bin, _even.bin	Interleaved byte separation
First Half/Second Half	_first.bin, _second.bin	Equal half division

3. Split the File

• Click the "Split" button
• The software will create two new files in the same directory as the original file:
  • If Odd/Even Split is selected: [OriginalFilename]_odd.bin and [OriginalFilename]_even.bin
  • If First Half/Second Half Split is selected: [OriginalFilename]_first.bin and [OriginalFilename]_second.bin

How Splitting Works

• Odd/Even Split: Separates the file into odd and even bytes. For example, a file with bytes A B C D will be split into A C (odd) and B D (even)
• First Half/Second Half Split: Divides the file into two equal halves. For example, a file with bytes A B C D will be split into A B (first half) and C D (second half)

4. Merge Files

• Click "Select Odd File" (or "Select First File" if in First Half/Second Half mode) and choose the first split file
• Click "Select Even File" (or "Select Second File" if in First Half/Second Half mode) and choose the second split file
• Click the "Merge" button
• The software will combine the files into a new file named merged.bin in the same directory as the first selected file

How Merging Works

• Odd/Even Merge: Interleaves bytes from the odd and even files. For example, if the odd file contains A C and the even file contains B D, the merged file will be A B C D
• First Half/Second Half Merge: Concatenates the first half and second half files. For example, if the first file contains A B and the second file contains C D, the merged file will be A B C D

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Code Logic

Splitting

• Odd/Even Split: Reads each byte sequentially and writes odd-positioned bytes to _odd.bin and even-positioned bytes to _even.bin
• First Half/Second Half Split: Reads the file and writes the first half of the bytes to _first.bin and the second half to _second.bin

Merging

• Odd/Even Merge: Reads one byte from the odd file and one byte from the even file alternately, writing them to merged.bin
• First Half/Second Half Merge: Reads all bytes from the first file followed by all bytes from the second file, writing them to merged.bin

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Example Workflow

Splitting a File

1. Load example.bin
2. Ensure "Odd/Even Split" is checked
3. Click "Split"
4. Output: example_odd.bin and example_even.bin

Merging Files

1. Select example_odd.bin as the odd file
2. Select example_even.bin as the even file
3. Click "Merge"
4. Output: merged.bin (identical to the original example.bin)

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Notes

• [ ] Backup your files before splitting/modifying
• [ ] Ensure you have write permissions in the directory where the files are located
• [ ] The log displays all actions and errors for easy troubleshooting

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Troubleshooting

Issue	Solution
"File not selected"	Ensure you have selected both files before clicking Merge
"File access denied"	Check file permissions and ensure the files are not open in another program
Incorrect output	Verify that you selected the correct files for merging

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Future Improvements

• [ ] Add support for splitting into more than 2 parts
• [ ] Implement CRC checking for file integrity
• [ ] Support drag-and-drop for file selection

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License

MIT