Skip to main content

wxPython COM Terminal

PySerial provides a convenient way to handle data transfer over COM ports. It works on most of the platforms. The program is written using wxPython to create a simple terminal emulator. It is pretty much similar to the example presented by PySerial itself.  However in this case, the UI is built on wx.Panel instead of wx.Frame, thus it is easy to embed the terminal emulator into any wxPython GUI.
All GUI components are populated on a single panel inherited from the wx.Panel. On the left a wx.TextCtrl is located as a terminal window. On the right, handful controls are added for for basic setup and control of the terminal window and the COM port. The controls on the right side can be hidden or shown at any time.This terminal supports ASCII mode and Hexadecimal mode. You can also save data to a disk file.


Since all the features are implemented on a wx.Panel (TermPanel), it can be embedded into any window including main frame window simply by creating an instance and passing a PySerial object(serial.Serial())

self.pnlTerm = TermPanel(self, serial.Serial())

You can find an example on which two such panels are populated to implement a UART sniffer.
Actual reading of COM port is done in a separate thread. Thus it does not affect the performance of the main thread much. However since it reads one byte at a time, it cannot handle long sequence of data stream very well. It is more suited to handle short and intermittent transactions.


<<source code>>
Labels:

Comments

Post a Comment

Popular posts from this blog

A Simple STM32 Example Project

Most of the embedded projects share certain initial steps. You need to confirm the clock settings before doing anything, then you want to have debug connection via a UART channel since it is cheap  but still it can provide useful information for debugging. Let us start with CubeMX. You select a device/board of your choice, set up the pinouts for one GPIO output and one UART port. Configure the clock if necessary then create a project. Clock Checking using SysTick The sanity of the clock setting can be done by checking the SysTick interval. All Cortex-M series core have SysTick timer by default, which should fire at 1msec interval while the MCU is active. In the STM32Cube, the SysTick is initialized by HAL_Init() call, which in turn calls SysTick_Config() in CMSIS. Once the SysTick is initialized, it generates 1 msec interrupt and this interrupt is handled by SysTick_Handler() according to the Cube framework. Source file 1 /** 2 * @brief This function han...
Post a Comment
Read more

STM32 USB MSD with SD Card

Build a low level driver for SD card, then the glue logic for FatFs and USB MSD is pretty much the same as Flash memory case posed before. In case of SD card, sector size is 512 in most of the cases. Thus the memory requirement is much relaxed. You can even allocate a file buffer that is bigger than the sector size. FatFs site has a  dedicated page for MMC/SDC, on which you can find fairly detailed explanation about how to interface MMC/SDC via SPI bus. Implementation should be straightforward until you encounter with cheap SD cards that do not behave very well. In such cases, you either have to protect your code with redundancy or just stick with quality devices. If you choose SanDisk or Kingston brand, you will be safe. ADATA on the other hand, frequently generates timeout error at first try. Most of the SD card sockets have a pin to detect the presence of the card. This pin is usually connected to GND pin or some other pin. You can use this to generate interrupt whenever ...
1 comment
Read more

STM32 USB MSC Device with FLASH memory

USB Mass Storage Class framework implements bulk-only-transfer (BOT) with SCSI protocol. USB packets from the host eventually converted SCSI transport commands by the middleware, in which data is exchanged (read / write) in the unit of logical block, typically 512 bytes. This SCSI commands works well with SD card system where a dedicated controller does the job of managing the actual memory elements. If you want to use a FLASH chip as a memory unit instead, you need to handle read / write operation directly. Fortunately, most of flash memory support 4KB block erase. This makes the 4096 bytes as a natural choice for the size of the logical block in the file usbd_storage_if.c. In this case, 8Mbit Flash memory was used. During initial enumeration, this information is registered to the host. The middleware maintains one logical block size of buffer and handles USB transaction where each payload is only 64 bytes. It then calls SCSI requests to store / retrieve data to / from physical...
Post a Comment
Read more