In recent years, the State Grid Corporation has vigorously explored the rural electricity market. The start of a new round of rural network transformation and upgrade work and the complete cancellation of revenue have created a wide range of application space for portable mobile toll terminal equipment. The relevant person in charge of the National Development and Reform Commission said that up to now, 29 provinces (autonomous regions and municipalities) other than Tibet and Xinjiang have held hearings on residential electricity tariffs. The local price authorities have carefully studied the opinions and suggestions put forward by the participants of the hearing, and further modified and improved the implementation plan on this basis. They have been introduced in mid-June 2012 and have been fully piloted nationwide since July 1st. Resident stepped electricity price reform plan. The formulation of a new calculation method for electricity charges will inevitably put forward new functional requirements for electric mobile charging terminals, that is, the software system or resource files of electric mobile charging terminals shall be updated in time to improve the performance of the terminal and thus meet the business needs of the charging system.
In response to the need for stability and reliability of electric mobile charging terminal systems, embedded systems have become the first choice. At present, there are two ways to update the software of embedded devices: one is to use a PC locally, download the software to the device through the serial port (or network port), and complete the software system upgrade; the other is to use the network for online upgrade. The former method can only be used for local software upgrade operation, which is not convenient for batch update. It is more suitable for laboratory debugging and small batch production of equipment. The latter method can be used for batch upgrade of online terminals through the network. But in fact, many terminal devices do not integrate the online upgrade function, that is, the function upgrade of the terminal is impossible. Therefore, we strive to find a way to upgrade the terminal functions in some way without making any changes to the terminal, making it impossible to become possible.
1 Strategy design
Information consists of many bytes, one or more bytes form an information unit, define a name, and express a definite meaning. In order to ensure the correct transmission of information between the platform and the terminal, the information can be organized according to a certain structure in a pre-agreed manner. Tables 1 and 2 give the structure of the information.
The composition of information can also use a simple, general hypertext markup language, such as HTML language, XML language, etc. HTML text is descriptive text composed of HTML commands, which can explain text, graphics, animations, sounds, tables, links, etc. HTML document production is not very complicated and powerful, and supports file embedding in different data formats.
Use the format described in Table 1 or Table 2 to organize the information format. If the terminal does not have an online upgrade function, then to complete the function upgrade of the terminal that has been sold to the customer, the terminal can only be sent back to the manufacturer, or find a factory staff to the customer Use the PC to download the software to the terminal through the serial port (or network port). If the B / S architecture is used to design the terminal and platform, and GPRS is used for data interaction, data transmission will be a thorny problem (it can be ignored when using the wired method) [1]. Taking all the above factors into consideration, a strategy for upgrading the terminal functions without any changes to the terminal firmware is proposed. In the implementation process, the design ideas of thin client and B / S architecture are integrated, that is, HTML language is added to the traditional communication protocol, so that the terminal can adapt to the new with a slight increase or no increase in data traffic. Business needs.
2 Specific implementation
The data interaction in the distributed electric power mobile charging system is carried out by means of terminal requests and platform responses. Add HTML or XML communication protocol on the basis of YD / T 1363.3-2005 fixed communication protocol, that is, use the HTML or XML part as one or several fields in the fixed communication protocol INFO. Send data fields in HTML or XML format at the sending end; perform data verification and parsing in the format of a fixed protocol at the receiving end [2], and the individual data fields parsed out are HTML or XML standard language. In order to adapt to changes in the needs of system development and ensure that the system construction has good independence, standardization, compatibility, flexibility, openness and scalability, the specific inclusion relationship is shown in Figure 1.
Kara offers a wide range of illuminated and non-illuminated Rocker Switches.In this series,Rated current 6A,10A,16A,Ranging from 1 to 6 poles,with many styles of colors and functions. Certifications include UL, CSA, TUV, CE, and more.
Why choose us?
1)As a manufacture, all of our switch parts are made by our own factory in Ningbo. So, price is competitive.
2)We have our own UL testing lab in Taiwan, so quality can be guaranteed.
3) We can provide you with different types of rotary switches for your selection.
4) Various operating force,height and colour for one switch for your choice.
5) Safety, on-time delivery, excellent quality with competitive price.
6) MOQ: 1000pcs,mixed order acceptable, welcome trial order.
7) OEM and ODM professional design.
8) We can provide free samples for your test.
Small-Sized Rocker Switches,Round Rocker Switch,Small Rocker Switch,Mini Rocker Switch
Ningbo Kara Electronic Co.,Ltd. , https://www.kara-switch.com