Since ancient times, measurement and weighing systems have not only been symbols of fairness and impartiality, but also the cornerstone of commercial credibility. Electronic weighing scales, as indispensable measuring tools in daily transactions, the accuracy of their measurement values directly affects the livelihood of society. Currently, a large number of experts and scholars have conducted research on methods and approaches for cheating electronic weighing scales [1][2]. The cheating methods and principles of electronic weighing scales have gained rich experience through previous studies, and corresponding preventive measures have been proposed [3][4][5]. However, detailed research on software cheating through password input is relatively scarce. This article, based on daily calibration practices, summarizes and analyzes the sources and implementation methods of password cheating, providing important references for measurement and inspection departments and consumers for identifying and preventing cheating scales.
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The implementation methods of software cheating
Currently, cheating through password input has become the main method of cheating in the market. The core method is to implant a dedicated cheating program in the electronic weighing scale chip. Specifically, a program is developed using C language or assembly language, compiled by a compiler to generate machine code, and then written into the chip using a programmer [1]. Due to the different formats of chip files from different manufacturers, the generated machine codes are also different.
When the electronic weighing scale with the cheating program is enabled, it requires entering a specific password in the control panel and using different buttons on the panel to falsely increase the weight (10% to 100%). To evade detection, merchants usually use methods such as power-off restart, special keyboard operations, and one-click restoration of the indicated value, or through dual-switch cheating (such as installing cheating switches on the reset button and cumulative button).
Therefore, software cheating has the characteristics of strong concealment, simple operation, and one-click restoration, becoming the main method of cheating for electronic weighing scales at present. 1
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Software Cheating Usage Pattern
Through practical experience, it has been found that the cheating electronic pricing scales with embedded software programs usually have a multi-digit super password. The super password is often the code set by the code compiler for cheating purposes when the software program is implanted. In reality, a single super password often involves a large number of the same type of software cheating electronic pricing scales. Obtaining a super password is helpful in cracking a batch of software cheating electronic pricing scales sold by the same seller. Ultra
The settings function for the level password includes:
(1) Setting a simple operation password for accessing the cheating program;
(2) Defining the starting weight or range for cheating (that is, the cheating program will be triggered only when the weighed weight reaches the set value);
(3) Configuring the virtual increment of weight corresponding to each key combination;
(4) Setting the key for quickly exiting the cheating mode.
After the settings are completed, the user can start the cheating program by inputting the preset usage password (usually a combination of numbers + function keys), and quickly exit the cheating mode when needed.
Generally, the cheating operation password has high flexibility, and its complexity is determined by the vendor, while the super password is relatively fixed.
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Methods for obtaining software cheating passwords
In actual use, users usually start the cheating program by inputting a combination of numbers + function keys (such as the removal key or reset key). For ease of operation, the cheating passwords for mobile vendors and roadside stalls are mostly in the form of simple numbers + function keys. This characteristic provides a preliminary method for detection personnel to identify cheating scales. However, for obtaining complex passwords, it is difficult to achieve solely through manual operation, and requires the use of electronic weighing scale cheating code intelligent detection equipment.
(1) Detection personnel manually test to obtain the password. By manually testing the digital password + function keys (mostly simple number keys + removal key or simple number keys + reset key) for detection. The specific operation is as follows: click each number key one by one and then click the function key, observe the changes in the display window. Normally, when pressing the number key, the corresponding number will be displayed in the unit price window. If it enters the cheating mode, it will display an inputted number (such as 0, or other set fields), accompanied by a "ding" sound indicating that the electronic weighing scale has entered the cheating mode. With
After that, the inspectors can place standard weights on the scale and press keys M1 to M7 or unit 1 to unit 7 to observe the changes in the weight display window.
The discovered cheating scales usually set different weight virtual increments for each key. When the virtual increment is large, the display value of the 1000g standard weight can reach 2000g.
This method is only applicable to software cheating electronic price-counting scales with simple passwords. It can be attempted by manually inputting numbers within 100. However, for complex passwords (such as combinations of multiple digits), the efficiency of manual testing is relatively low.
(2) The intelligent detection equipment obtains the password. For complex passwords and super passwords, the intelligent detection equipment for cheating codes of electronic price-counting scales developed by the Inspection, Testing and Certification Institute of Wuxi City has become an efficient solution. The equipment learns the electronic price-counting scale panel and simulates the input of all possible digit combinations manually, and captures real-time abnormal changes in the display panel of the electronic price-counting scale. Once a suspected cheating password is detected, the equipment can automatically record and analyze it, thereby quickly locating the usage of passwords and super passwords, as shown in the figure below. Examples of super passwords discovered:
Brand A: 97583 + Off-Weight Button; 12121 + Off-Weight Button
Brand B: 19867 + Off-Weight Button
Brand C: 64909 + Off-Weight Button
Brand D: 3085 + Off-Weight Button
Common cheating operation password examples:
1 + Off-Weight Button; 3 + Off-Weight Button; 6 + Off-Weight Button; 9 + Off-Weight Button;
25 + Off-Weight Button; 56 + Off-Weight Button; 123 + Off-Weight Button; 456 + Off-Weight Button;
789 + Off-Weight Button; 1 + Zero Button; 3 + Zero Button; 6 + Zero Button;
9 + Zero Button, 53 + Zero Button, etc.
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Daily prevention methods
Although obtaining the cheating codes of electronic price-counting scales is an effective means for metrologists to identify cheating scales, this method is not universal in daily consumption scenarios. Since cheating scales are mostly concentrated in mobile vendors and other places with greater regulatory difficulties, enhancing consumers' awareness of prevention and encouraging their active participation in supervision have become the key to curbing such illegal behaviors. Therefore, the following simple and easy-to-implement preventive measures can be adopted in daily life: 2
References
(1) Restart the electronic scale: Require merchants to turn off the electronic scale and restart it, then proceed with weighing directly to avoid the influence of software cheating.
(2) Use mobile phone as weights: Utilize the "mobile phone as weights" campaign launched by local market supervision bureaus to test the mobile phone as the standard weight. Since the cheating threshold is usually higher than the weight of the mobile phone, consumers can place the mobile phone on the goods after weighing and observe whether the weight change is consistent with the weight of the mobile phone.
(3) Use fair scales: When shopping in the market or supermarket and suspecting short weight or shortage, you can conduct a re-weighing on the fair scale to verify the weight of the goods. 5
Electronic price-keeping scales, as indispensable measuring tools in modern commercial transactions, their accuracy and fairness directly affect the interests of consumers and the fair competition of the market. As the means of cheating on electronic price-keeping scales become increasingly concealed and complex, especially through software cheating, new challenges have arisen for measurement inspection and the protection of consumers' rights and interests. This article, through an in-depth analysis of the software cheating methods of electronic price-keeping scales, reveals the setting patterns and usage methods of cheating passwords, and proposes corresponding detection and prevention measures. By continuously optimizing technology, strengthening market supervision, and raising public awareness, we can effectively curb the cheating behavior of electronic price-keeping scales and maintain the fairness and integrity of market transactions.