🔧 HexEdit

A command-line tool for Hex/Bin file editing, built for MCU developers Merge · Delete · Cut · Fill · Format Conversion

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✨ Features

Feature	Description
🔄 Format Conversion	Bin ↔ Hex conversion with custom start address
➕ File Merge	Merge up to 64 Hex/Bin files into one output
✂️ Region Delete	Delete data at a specified address range
🔍 Region Cut	Extract data from a specified address range
🎨 Region Fill	Write a specified byte to an address range (zero-fill / pad)
📦 Smart Padding	Auto-fill gaps between Bin files, default 0xFF

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🚀 Quick Start

Basic Usage

HexEdit.exe [command] -f <input file> -o <output file>

Simplest Examples

# Bin to Hex (STM32 default Flash start address 0x08000000)
HexEdit.exe -x 0x08000000 -f firmware.bin -o firmware.hex

# Hex to Bin
HexEdit.exe -f firmware.hex -o firmware.bin

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📖 Command Reference

Commands

Command	Description	Format
--add	Merge files (default operation)	--add -f a.bin -f b.bin -o out.hex
--del	Delete a specified address range	--del <addr>:<length>
--cut	Cut a specified address range	--cut <addr>:<length>
--set	Fill a specified address range	--set <addr>:<length>:<byte>
--version	Print version info
--help	Print help info

Parameters

Parameter	Description	Example
-f	Input file (up to 64)	-f a.bin -f b.hex
-o	Output filename	-o output.hex
-b	Set subsequent input and output files to Bin format	-b -f a.bin
-h	Set subsequent input and output files to Hex format	-h -f a.hex
-x	Set start address for Bin file (must come before -f), appended directly if omitted	-x 0x08000000
-i	Set fill byte for Bin output (0xFFFFFFFF for split output)	-i 0x25

Address Format

<hex address>:<decimal length>[:<hex byte>]

Example: 0x08000000:4096:0xFF → Start at address 0x08000000 (STM32 Flash start), length 4096 bytes, fill value 0xFF

File Type Detection Rules

⚠️ Important: Once -b or -h is specified, all subsequent input and output files use that type until -b or -h is encountered again.

• Not specified: .bin extension → Bin, others → Hex
• -b specified: all subsequent files treated as Bin
• -h specified: all subsequent files treated as Hex

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💡 Usage Examples

📎 File Merge

Case 1: Bin + Bin → Hex

Merge two Bin files at specified addresses, output a Hex file. Typical use case: BootLoader + APP firmware.

boot.bin → start address 0x08000000 (BootLoader)
app.bin  → start address 0x08010000 (Application)

HexEdit.exe --add -x 0x08000000 -f boot.bin -x 0x08010000 -f app.bin -o output.hex

Case 2: Bin + Bin → Bin

boot.bin → start address 0x08000000 (BootLoader)
app.bin  → start address 0x08010000 (Application)

HexEdit.exe --add -x 0x08000000 -f boot.bin -x 0x08010000 -f app.bin -o output.bin

💡 Bin files have no address info. If boot.bin is shorter than 0x10000 (64KB), gaps are filled with 0xFF by default. Use -i to customize the fill byte, set 0xFFFFFFFF to split output into separate files.

Case 3: Hex + Hex → Hex

Merge two Hex files into one Hex file.

HexEdit.exe --add -f boot.hex -f app.hex -o output.hex

Case 4: Hex + Bin → Hex

Merge a Hex file with a Bin file, output a Hex file.

boot.hex → Hex file (contains addresses)
app.bin  → start address 0x08010000 (Application)

HexEdit.exe --add -h -f boot.hex -b -x 0x08010000 -f app.bin -o output.hex

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✂️ Data Delete

Case 1: Delete from Bin File

Delete 256 bytes starting at address 0x08010000.

HexEdit.exe --del 0x08010000:256 -x 0x08010000 -f app.bin -o output.hex

⚠️ Recommended to output Hex file. Deleting from the middle of a Bin file will split it into two segments.

Case 2: Delete from Hex File

Delete 256 bytes starting at address 0x08010000 (0x08010000 ~ 0x080100FF).

HexEdit.exe --del 0x08010000:256 -f app.hex -o output.hex

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🔍 Data Cut

Case 1: Cut from Bin File

Extract 4096 bytes (1 Flash Page) starting at address 0x08010000.

# Output Hex
HexEdit.exe --cut 0x08010000:4096 -x 0x08010000 -f app.bin -o output.hex

# Output Bin
HexEdit.exe --cut 0x08010000:4096 -x 0x08010000 -f app.bin -o output.bin

Case 2: Cut from Hex File

Extract 4096 bytes starting at address 0x08010000 (0x08010000 ~ 0x08010FFF).

# Output Hex
HexEdit.exe --cut 0x08010000:4096 -f app.hex -o output.hex

# Output Bin
HexEdit.exe --cut 0x08010000:4096 -f app.hex -o output.bin

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🎨 Data Fill

Case 1: Zero-fill Bin File

Set 4096 bytes starting at 0x08010000 to 0x00.

# Output Hex
HexEdit.exe --set 0x08010000:4096:0x00 -x 0x08010000 -f app.bin -o output.hex

# Output Bin
HexEdit.exe --set 0x08010000:4096:0x00 -x 0x08010000 -f app.bin -o output.bin

Case 2: Fill Hex File

Set 4096 bytes starting at 0x08010000 to 0xFF (0x08010000 ~ 0x08010FFF).

# Output Hex
HexEdit.exe --set 0x08010000:4096:0xFF -f app.hex -o output.hex

# Output Bin
HexEdit.exe --set 0x08010000:4096:0xFF -f app.hex -o output.bin

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❓ FAQ

Q: What is the difference between Hex and Bin files?

Bin is raw binary data with no address information — the file content is the firmware bytes themselves. Hex (Intel HEX) is a text format where each line contains address, data, and checksum, natively supporting non-contiguous address ranges. In MCU development, compilers typically generate Hex files, while flashing tools support both formats.

Q: What happens if -x is not specified for a Bin file?

Without -x, the Bin file data is directly appended to the output with no address offset. When merging multiple Bin files, always specify -x to avoid data overlapping.

Q: Can addresses overlap during merge?

Yes — later input files overwrite data at the same addresses from earlier files. If you need to preserve gaps between regions, use -i to specify a fill byte.

Q: Why are there large blocks of 0xFF in the merged Bin output?

Bin files contain no address information. When merging, if there is a gap between the start addresses of two Bin files, HexEdit automatically fills it with 0xFF. Use -i to customize the fill byte, or set 0xFFFFFFFF to split the output into separate files.

Q: What does -i 0xFFFFFFFF (split output) mean?

When merging files with non-contiguous addresses, setting -i 0xFFFFFFFF splits the output into multiple independent Bin files instead of connecting them with fill bytes. Useful when there are large gaps between BootLoader and APP regions.

Q: Why is the output Bin file larger than the source files?

Bin output fills address gaps. For example, if BootLoader ends at 0x0800FFFF and APP starts at 0x08010000, the output is compact with no gap. If there is a gap, it is filled with 0xFF (or the byte specified by -i). Set -i 0xFFFFFFFF to split output and avoid padding.

Q: How does delete affect Bin files?

Bin files are continuous binary data. Deleting from the middle splits the data into two disconnected segments. It is recommended to output Hex files for delete operations (Hex format natively supports non-contiguous addresses).

Q: What is the scope of -b and -h?

These are mode-switching parameters. Once specified, all subsequent input and output files use that type until -b or -h is encountered again. Without them, file type is inferred from the extension: .bin → Bin, others → Hex.

Q: What is the maximum number of files for merge?

Up to 64 input files.

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📋 Changelog

Version	Date	Changes
1.0.0	—	Initial release: merge, delete, cut, fill, format conversion