Arm And Linux-based Three-dimensional Electromagnetic Gathering Station Embedded Control Systems

As one of the important indicators of the developing level of 3D EM exploration, the performance of 3D EM acquisition station is critical. As the control center in 3D EM acquisition station, the control system is the most important part. Therefore, the study of the control system in 3D EM acquisition station is of great significance.In consideration of the benefits of ARM processor, such as small scale, low power consumption, and low cost, and the benefits of Linux OS such as higher reliability, resource richness, open source, and cost free, this work implemented an embedded control system based on ARM microprocessor with embedded Linux OS. The hardware design based on ARM has good scalability and the software design based on embedded Linux operating system improves system reliability and flexibility. Their combination is the basis of a versatile control system. It overcomes the deficiencies in traditional X86 and DOS/Widows combination, such as high power consumption, not fully open sourced and high copyright fee. and it effectively reduces power consumption and cost of the instrument.This article discusses in detail the process building an embedded control system in 3D EM acquisition station from hardware to software platform.The hardware design employs the 32-bit embedded ARM microprocessor AT91RM9200 as the main controller. To meet the demand of acquisition station, a variety of hardware resources were expanded, including large-capacity memories (32MB SDRAM,8MB NOR flash, 1GB NAND flash), UART interface, cable network interface, ZigBee wireless communication, USB, Temperature sensor, RTC clock, SPI, I2C and SSC interface. The paper details the overall hardware design and the realization.According to the design requirements of the embedded control system, the software development platform was established based on the hardware system. The paper details the establishment of U-Boot-1.3.4 boot system and Linux-2.6.21 operating system and gives the porting steps. At the same time, the character device drivers such as UART, SPI, RTC, USB, LM75 temperature sensor were also ported and tested. The thesis describes the test methods and test results. In default the Linux-2.6.21 kernel does not provide SSC (synchronous serial communications) device driver. This work implements the SSC device driver and SSC communication between AT91RM9200 and DSP56309 chips. The paper also describes the implementation in detail.Currently the control system was integrated into the whole acquisition station and tested. The test shows that the power consumption, reliability, storage capacity and signal processing capabilities meet the design requirements.