How To Extract and Parse ASCII Frames from a Scale in vNode

This code snippet is designed to extract specific information from an ASCII frame received from a scale and parse it using vNode, a server-side JavaScript platform. Here's a breakdown of the main components:

Receiving the Frame: The code likely operates within a system that receives data from a scale, which is stored in the variable $.rx.

Logging the Received Frame: The line $.logger.debug("Received frame: " + frame); logs the received ASCII frame for debugging and monitoring purposes.

Extracting Relevant Information: The substring() method is used to extract a portion of the frame (frame.substring(5, 12)) starting from the 5th character position up to the 12th character position. This extracted substring likely contains specific data of interest from the scale, such as weight or identification information.

Logging the Extracted Data: The extracted substring (tag) is logged for further analysis or processing using $.logger.debug().

Setting a Variable: The extracted substring (tag) is stored in a vNode variable named "Weight" using $.variableSet().

Logging Success: Finally, a log message indicating successful writing or processing of the extracted data is generated using $.logger.debug().

Overall Objective:
The main objective of this code is to receive an ASCII frame from a scale, extract specific information from it (such as weight), and then store or process that information using vNode. This process enables the integration of scale data into a larger system or application for monitoring, control, or analysis purposes.

Certainly! Here are the steps to set up the communication channel, create a device, and configure transactions for receiving and parsing data:

1. Create Communication Channel:

   • Navigate to the communication channel configuration section in vNode.
   • Choose the appropriate communication type based on the connection method (e.g., serial, TCP/IP).
   • Provide necessary details such as port number, baud rate (for serial communication), IP address, and port number (for TCP/IP)
     
     
     
     

2. Create Device:

• Navigate to the device management section in vNode.
• Click on "Add Device".
• Enter a name and description for the device

3. Configure Receive Data Transaction:

• Within the device configuration, navigate to the transactions section.
• Click on "Add Transaction".
• Choose the appropriate transaction type (e.g., Receive Data).
• Configure the transaction settings such as data format, expected data length, timeout, and any other relevant parameters.
• Save the transaction settings.

4. Configure Parse Data Transaction:

• Similar to step 3, add another transaction within the device configuration.
• Choose the appropriate transaction type for parsing data (e.g., Parse Data).
• Configure the parsing rules or scripts to extract relevant information from the received data.
• Save the transaction settings.

5. Script:

In the vNode scripts section, create a new script or edit an existing one to handle the reception and analysis of the frame.

Utilize the functions and methods provided by vNode to read the received frame.

Analyze the structure of the frame to identify the relevant values you want to map to tags.

Use programming logic, regular expressions, or other methods to extract the necessary values from the frame.

Assign the extracted values to specific tags you have created in vNode to represent the desired information.

Ensure proper handling of errors and exceptions that may arise during the frame interpretation process. 

Created by JF