Triple Char Test

Overview

This project demonstrates of testing a ascii character three times when transmitted over a serial connection. The character will be sent from one serial device, CP210x UART Bridge, to another device and a Oscilloscope will read the data and display the character and a camera looking at the Oscilloscope will also read the character.

The three test points are:

1. (T1) Scope reading over TCP/IP
2. (T2) Web cam OCR looking at the scope
3. (T3) The receiving serial device

Char -> Serial Device->|<- Silicon Labs CP210x UART Bridge 
                       |
T1 <--- Scope Data <---|
            |          |
T2 <---- USB Cam OCR   |
                       |
T3 <- Serial Device----|<- Silicon Labs CP210x UART Bridge

Hardware Used

• Rigol 1054z Oscilloscope
• 2 x Silicon Labs CP210x UART Bridge
• Logitech USB C Web Cam

Packages Used

• opencv-python
• pyserial
• pytesseract
• pytest
• PyVISA
• PyVISA-py

Configuration

The tests/conftest.py file looks for $HOME/triplechartest.txt" file. And in that file is a comma separated list of values.

For example:

# Serial Device,Serial Device,Vide0 Device,Rigol Scope IP Address
/dev/ttyUSB0,/dev/ttyUSB0,4,127.0.0.1

To Install and Run

$ git clone https://github.com/tgu-ltd/triplechartest
$ cd triplechartest
$ poetry install
$ poetry shell
$ pytest

Captured Images

Rigol Screen with Event Table

Camera Character Capture

Files Read and Written

Three files are written during the tests:

1. main.png is a image of the webcam
2. test.png is a captured region of the webcam image
3. screen.png is a screen shot loaded from the rigol scope

One file is read during the tests:

1. rigol_setup.bin is used to setup the rigol 1054z. This file can be generated using the Rigol(ip=x.x.x.x)._read_setup() after manually setting up the scope.