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For low-level communication with a comport.

COMTool Communications Utility

Microsoft support for Windows XP has ended. For more information, please visit

The COMTool is an easy to use serial communication terminal program that transmits and receives bytes to practically any device connected to a PC's COM port.

Some of the COMTool features include:
1. Transmits and receives data in either HEX or ASCII format.
2. Pre-configured and user selectable COM port settings. Selectable COM port settings include baud rate, parity, data bits, stop bit, and hand shaking mode.
3. Automatic calculation of checksum using 2's Complement, XOR'd, and Modbus CRC16 formats.
4. Conversion of hex to integer and integer hex using selectable Big-Endian or Little-Endian format and sign or unsigned format.
5. Pre-configured list of commands by product with description and command syntax. Commands may be edited and persisted for later use.
6. Ability to copy received bytes to the clipboard using custom formats and saving clipboard contents to file.
7. Provides scripting capability with the ability open, edit, run, and save script commands.

2.8 Added COM IO status inidicators. Fixed error where new scripts could not be saved unless the file already exists. Added ability automatically clear received data before transmitting command.
2.7 Added scripting capability.
2.6 Fixed error in calculation of SEI Checksum.
2.5 Fixed command database insert, edit, and delete synchronization errors.
2.4 Fixed command database import routine and set the minimum size for the send and receive textboxes so that they don't disappear when the COMTool application is resized.
2.3 Added option to select big-endian vs little-endian. Added option for signed vs unsigned integer display. Selecting product type now updates baud rate and parity fields.


Download , Windows Vista | 7 | 8 (32 & 64 bit) Version 2.8 (12/03/2013)

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