Research on Windows CE embedded Navigation System (hardware platform selection)

1.1.1 hardware platform Selection

The core component of the embedded system is various types of embedded processors. According to incomplete statistics, the total number of embedded processors worldwide has exceeded more than 1000, and the popular architecture has 30 series. However, unlike the global PC market, there is no microprocessor or microprocessor company that can take the lead in an embedded system. In 32-bit CPUs alone, there are more than 100 types of embedded microprocessor. Because of the great differences in the design of embedded systems, the selection is diversified.

Investigating the CPU vendors listed on the market, some companies such as Motorola, Intel, and AMD are well-known, while some small companies such as QED (Santa Clara. CA) although well-known, it also produces excellent microprocessor. In addition, some companies, such as arm and MIPS, only design but do not produce CPUs. They assign production rights to semiconductor manufacturers around the world. Arm is an influential microprocessor manufacturer in embedded systems in recent years. Its design is very suitable for small power supply systems. Apple uses arm in the Newton handheld computer, and several other digital wireless phones are also using arm.

When selecting a processor, we mainly consider the following factors: processing performance, technical metrics, power consumption, software support tools, built-in debugging tools, and whether the supplier provides the evaluation board.

1. Processing Performance

The performance of a processor depends on multiple factors, such as clock frequency, internal register size, and whether the command processes all the registers in a peering manner. For many embedded systems that require processors, the goal is not to select the fastest processor, but to select the processor and I/O subsystem that can complete the job. For high-performance application designs, we recommend that you consider some new processors at a relatively low price, such as IBM and Motorola Power PC.

2. Technical Indicators

At present, many embedded processors integrate the functions of peripheral devices, reducing the number of chips and the development cost of the entire system. The first consideration for developers is whether the hardware required by the system can be connected to the processor without the need for too much glue logic (GL, glue logic. The second is to consider some supporting chips of the processor, such as DMA controller, Memory Manager, interrupt controller, serial device, clock, and so on.

3. Power Consumption

The largest and fastest growing market for embedded microprocessors is handheld devices, electronic notebooks, PDAs, mobile phones, GPS navigators, Smart appliances, and other consumer electronic products. Among these products, the microprocessor is typically characterized by high performance and low power consumption. Many CPU manufacturers have already entered this field. Today, users can buy an embedded microprocessor, which is as fast as the Pentium in a notebook, and it is only powered by a common battery, and the price is very low. If it is used for industrial control, the consideration for this aspect is weak.

4. Software Support Tools

Only one processor does not support good software development tools. Therefore, selecting appropriate software development tools will play a very good role in system implementation.

5. built-in debugging tools?

If the processor has built-in debugging tools, the debugging cycle can be greatly reduced to reduce the debugging difficulty.

6. Does the supplier provide the evaluation board?

Many processor vendors can provide evaluation boards to verify that theories are correct and decisions are appropriate.