China
Africa
Explore chapters and articles related to this topic
Microflow Cytometer Electronics
Published in Frances S. Ligler, Jason S. Kim, The Microflow Cytometer, 2019
Jeffrey S. Erickson, Dustin J. Kreft, Matthew D. Kniller
When selecting a microcontroller or microprocessor, there are a few issues that should be considered. First, it should have enough digital input and output lines to control and read from all of the other electronics on the board. Second, the clock speed must be sufficient to handle data streams and any operations that the microprocessor will perform on it. Microprocessors and microcontrollers are rated in terms of the number of bits per clock cycle operation. An 8-bit microcontroller can handle 8-bits of data per clock cycle, while a 16-bit microcontroller can handle twice the throughput. Another consideration is the instruction cycle time of the microcontroller. Some microcontrollers can process instructions at 1 per clock cycle and others may require 4 or more clock cycles. For example, an 8 MHz chip which can compute most instructions in one clock cycle will run at roughly the same throughput as a chip that runs at 24 MHz but requires 3 clock cycles per instruction. Although there is a trade off, usually microcontrollers and microprocessors that require more cycle time may have an internal pipe-line. This can increase computation when handling very large and complex algorithms.
Electronic Equipment for a GPS System
Published in Franjieh El Khoury, Antoine Zgheib, Building a Dedicated GSM GPS Module Tracking System for Fleet Management, 2018
Franjieh El Khoury, Antoine Zgheib
We distinguish three types of microcontrollers based on the number of bits (Agarwal 2015; Kamal 2012; Parai et al. 2013): an 8-bit microcontroller, a 16-bit microcontroller, and a 32-bit microcontroller. The 8-bit microcontroller has an internal bus of 8-bit (e.g., Intel 8031/8051) where the Central Processing Unit (CPU) or the Arithmetic Logic Unit (ALU) can process 8-bit data. This type of microcontroller is used in position control and speed control.The 16-bit microcontroller performs greater precision and good performance as compared to the 8-bit microcontroller. This type of microcontroller is used in high-speed applications such as servo control systems, robotics, and other applications. For example, extended Intel 8096 and Motorola MC68HC12 families are considered to be 16-bit microcontroller units.The 32-bit microcontroller uses the 32-bit instructions to perform the arithmetic and logic operations. This type is developed for the purpose of very high-speed applications in image processing, telecommunications, intelligent control systems, and other applications. For example, the Intel/Atmel 251 family, the PIC3x, and the ARM are considered to be 32-bit microcontroller units.
The CPU and a microprocessor system
Published in Stuart Anderson, Microprocessor Technology, 2012
Referring again to Figure 3.2, it can be seen that there are three main connecting lines, the data, address and control buses. Every memory location (RAM or ROM) has a unique address which allows the CPU to access it for read or write operations. If the address bus which carries this information consisted of only eight lines, the memory size would be only 256 bytes; you should recall that an 8-bit register can only hold the numbers 0 to 255, i.e. 0000 0000 to 1111 1111 in binary. With 16 address lines, 65536 locations can be directly addressed (64K), hence many systems will have a 16-line address bus.
A color image encryption scheme using customized map
Published in The Imaging Science Journal, 2023
Step 1: The literature claims that the chaotic sequence is generated using customized map with initial conditions and system parameters. As shown in equations (12)–(15), the sequence is then transformed into an integer value from 0 to 255, where x_4_ is the generated chaotic sequence using the customized map. Step 2: The permuted integer sequence is converted to an 8-bit binary sequence and encrypted using the associated DNA rule. Using Algorithm 2, for instance, the DNA sequence corresponding to the numerical sequence 00011011 is ACTG. Where Simage is the image components pixels after the scrambling process. Step 3: The DNA addition operation was also used to encrypt the DNA sequence. Where D1 is the sequence obtained from the first level of the DNA encoding rule. Step 4: The integer sequence produced by the chaotic map is then transformed into an 8-bit binary sequence. Eventually, the binary sequence is converted into a DNA sequence using the suitable DNA encoding rule, where k is the generated chaotic sequence. Step 5: Similarly, the acquired DNA sequence is encrypted using DNA addition. Where D2 is the sequence obtained from the DNA encoding rule, and D3 is the sequence from DNA addition.
Analysis of the dynamics of land use change and its prediction based on the integration of remotely sensed data and CA-Markov model, in the upstream Citarum Watershed, West Java, Indonesia
Published in International Journal of Digital Earth, 2019
Fajar Yulianto, Taufik Maulana, Muhammad Rokhis Khomarudin
The satellite image pre-processing stage was performed to convert the Digital Number (DNs) value to the reflectance value. In the standard products, Landsat 5 TM and Landsat 7 ETM+ have 8-bit unsigned integer format data. Meanwhile, the products Landsat 8 OLI/TIRS have 16-bit unsigned integer format data. Processing standard reflectance value needs to be done to address the differences in values format DNs on the satellite image. The conversion process DNs value to the reflectance values consists of two stages. The first stage of the conversion process is carried DNs value to the radians value. The second stage process is carried radian value to the reflectance values. Details on the second stage of the process refer to Chavez (1988), Luca, Michele, and Silvia (2013), USGS (2013a, 2013b).
Optimizing latency time of the AR system through glyph detection
Published in International Journal of Computers and Applications, 2019
Suman Bhakar, Devershi Pallavi Bhatt
The RS 232 protocol transmits and receives the serial data between two systems. Figure 4 shows that the CPU sends 8 bit binary bit + 1 start bit + 1 stop bit through serial communication (Data Transmit Equipment) at baud rate 9600 bit/second to the microcontroller. The microcontroller received data (R×D) and transmits the ‘2’ 8 bit + 1 start bit + 1 stop bit to CPU through the serial port. To calculate the actual transmission flow rate through the RS 232 protocol, the first step is to enable the CPU microsecond timer with a baud rate of 9600 bit/second and open the serial port communication. The second step is CPU transmits the data (T×D) H = 72(ASCII) to the microcontroller. Binary representation of data bit at (T×D) is (0/1 0100 1000 0/1) where 0/1 is the start bit, 8 bit binary bit, and 0/1 stop bit. The microcontroller receives the 10 bit and transmit ‘2’ 8 bit + 1 start bit + 1 stop bit to application (central processing unit). Total transmit and receive time of system through RS 232 is 2.4 milliseconds.