I. How are embedded software specializations categorized?
Embedded software can be specifically divided into three categories:
1. Embedded Driver Engineer
Writing and porting drivers for various chips (such as audio chips) and optimizing hardware device drivers (such as temperature and humidity sensors) requires expertise in various hardware interface protocols (such as I2C), system scheduling, semaphores, locking mechanisms, and so on. This is the most challenging aspect of driver development. These developers are typically well-rounded software and hardware professionals. Embedded driver engineers generally refer to Linux-based driver development engineers, who need to be proficient in Linux driver frameworks (platform framework, input subsystem framework, etc.) and write drivers in conjunction with the chip itself. The quality of the driver largely determines the quality of a product. The industry definition of a driver engineer is that it takes three years to even begin to understand the field, highlighting the high entry barrier.
2. Embedded Systems Engineer
The main task is to write firmware, port operating systems to different platforms, and optimize the system according to application scenarios. This requires familiarity with the entire operating system composition and scheduling, and a very high level of stability in the firmware. If the system is unstable, the drivers and applications will be useless.
3. Embedded Application Engineer
Writing business logic programs and calling interfaces provided by driver engineers to control devices involves a very wide range of software development processes. It is mainly developed using C, but often involves various languages such as C++, Java, Python, JavaScript, and PHP, as well as various scripting languages, databases, front-end and back-end, various communication protocols, and even some protocols or concepts that have never been heard of before. It requires strong learning ability. This position is also the most in-demand in major companies. In a typical 10-person development team, the ratio of driver development, system development, and application development is 1:2:7.
II. Embedded Applications
(1) Embedded mobile database
A mobile database, in essence, is a database that supports mobile computing, encompassing two meanings: ① Users can access database resources online while on the move. ② Users can carry the database with them. A typical application is finding the nearest hospital from a moving ambulance. The system consists of a front-end mobile terminal and a back-end synchronous server. The mobile terminal has an embedded real-time operating system and an embedded database. Renmin University of China is developing this system, collaborating with Hopen to develop the front-end mobile terminal, nicknamed "Little Elf."
(2) Application of embedded systems in smart home networks
A smart home network (E-Home) refers to establishing a communication network within a home, providing necessary pathways for family information. Under the control of a home network operating system, and through corresponding hardware and actuators, it enables the control and monitoring of all home appliances and devices on the network. Its network structure inevitably includes a home gateway. The home gateway primarily integrates signals from the control and information networks and interfaces with the outside world for remote control and information exchange. Both the gateway and the control modules on individual appliances require embedded operating systems. These operating systems must be embedded, have good real-time performance, and support multiple users. The smart multimedia home gateway developed by Nanjing Dongda Mobile Internet Technology Co., Ltd. uses embedded Linux as its operating system. Communication between devices follows the Bluetooth communication protocol, and it can support multiple devices simultaneously accessing fixed-line telephone networks, the Internet, and other external networks.
(3) Embedded voice chip
Embedded voice chips, based on embedded operating systems, employ technologies such as speech recognition and synthesis, hierarchical phonetics architecture, and text processing models. They can be applied in various fields, including handheld devices and smart home appliances, providing these devices with user-friendly interaction methods and convenient usage. They can also be used in toys to create voice-controlled toys, realistic pets, and toys that can converse with humans. Furthermore, they can be used in in-vehicle communication devices to enable human-machine interaction. In mobile communication devices, for example, when a text message arrives on a mobile phone, we don't need to look at it; we can hear it instead.
(4) Embedded products based on small-range wireless communication protocols
The integration of short-range wireless access protocols, such as Bluetooth, with embedded systems will inevitably drive the widespread application of embedded systems. Recently, embedded products based on these protocols have emerged in large numbers, including various telephone systems, wireless briefcases, various digital electronic devices, and applications in e-commerce. These products, with their miniaturization and low cost, have opened up broad prospects for applications in home and office automation, e-commerce, industrial control, intelligent buildings, and various special applications.
