zhuyanzhen1/cdtp

数据链路层协议，只需要提供单字节的收发函数就可以移植这些协议。Data link layer protocols can be transplanted by providing a single byte transceiver function.

Data Transmit Protocol

            English / 中文

    This project is a derivative version of a lightweight data transmission protocol proposed and developed by the author when he participated in Robomaster high school summer camp in senior three. The main purpose is to realize the function of the transport layer. This protocol can be applied to various physical layers, such as UART, SPI, IIC, etc., which provides a guarantee for sequential data transmission. According to the requirements of the amount of data transmitted, the author divides the protocol into the following three different versions:

• Large Capacity Data Transmit Protocol: Infinite data length
• Mid Capacity Data Transmit Protocol: Data length is less than 128Byte
• Small Capacity Data Transmit Protocol: Data length is less than 3Byte

    Note: please choose a small data transmission protocol when the transmission capacity is met, because the larger the data transmission protocol, the larger the stack, the more complex the protocol processing and the greater the error probability, which is reflected in the longer interrupt occupation time (geometric increase) and the easier the stack overflow on the microcontroller.

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Porting Code：

1. Porting files "encrypt.c，encrypt.h，decrypt.c，decrypt.h，ioctrl.c，ioctrl.h" into your project
2. Realize the single byte transmit function in "ioctrl.c", which function name is common_sendbyte.
3. After receiving a byte，call the "common_receivebyte" function in "decrypt.c", as well deliver the received byte to buf.
4. After finished the previous steps，call the "xdtp_data_transmit" function to send a package; it'll trig the "xdtp_callback_handler" function in "ioctrl.c" if received a package.

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Bugs & Feature Requests

Please report bugs and request features using the Issue Tracker and follow these request:

1. Tab highlight when on different tab.
2. Don’t let the update disappear if the window is not in focus.

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License

The source code is released under a AGPL-3.0 License.

Affiliation：AcmeTech
Author: Yanzhen Zhu
Maintainer：YanzhenZhu, [email protected]

The product has been tested under Windows 10 and Ubuntu 22.04 LTS. This is research code, expect that it changes often and any fitness for a particular purpose is disclaimed.

cdtp's Issues

[Feature] Consider alternative framing bytes to improve UART protocol's robustness against interference

Verify steps

• 我已经在 Issue Tracker 中找过我要提出的请求
  I have searched on the issue tracker for a related feature request.
• 我已经仔细看过 Documentation 并无法自行解决问题。 I have read the documentation and was unable to solve the issue.

Description

Hi there,

I've been looking into your medium capacity data transmission protocol and noticed that it uses 0xFF as both frame header and frame tail. While this is simple and straightforward, it might lead to issues in situations where the UART communication is subject to interference.

When UART communication experiences external electromagnetic interference, an unexpected low-level signal (logical 0) might appear on the line. If the receiving end misinterprets this as a start bit and continues to detect high-level signals (logical 1) in the subsequent data bits, it may erroneously interpret it as a 0xFF byte. This can result in unstable communication and reduced protocol reliability.

To enhance the UART protocol's robustness against interference, I'd recommend considering alternative byte values for the frame header and frame tail, similar to the SLIP (Serial Line IP) protocol design. Using different and less likely byte combinations due to interference will help improve data transmission reliability in noisy environments.

Thank you for your work on this project!

Possible Solution

No response