How To Convert Serial Data To Parallel Data In Simulink
Now we got all data available after t = 5; That is the first element of the data. By using this method we can design a method to control data output. Matrix index selection can be controlled using a matlab function box using a simple code as below.
To use this system first you have to run the serial converter script to update variables in to the workspace. Then run the simulink model to perform required operations on simulink and finally the reshape matrix script to convert the data back to image format.
Property names are specified as character vectors. The data type of a property value is specific to the property. This section describes the syntax of each block implementation parameter and how the parameter affects generated code.
Output data might be in an invalid state initially if you insert pipeline registers. To avoid test bench errors resulting from initial invalid samples, disable output checking for those samples. For more information, see Ignore output data checking (number of samples).
To avoid test bench errors during the initial phase, determine the number of samples required to fully load the registers. Then, set the Ignore output data checking (number of samples) option accordingly. See also Ignore output data checking (number of samples) in Test Bench Stimulus and Output Parameters.
Number of parallel data paths, or vectors, to transform into serial, scalar data paths by time-multiplexing serial data paths and sharing hardware resources. The default is 0, which implements fully parallel data paths. See also Streaming.
Due to its relative simplicity and low hardware overhead (when compared to parallel interfacing), serial communications is used extensively within the electronics industry. Today, the most popular serial communications standard is certainly the EIA/TIA-232-E specification. This standard, which was developed by the Electronic Industry Association and the Telecommunications Industry Association (EIA/TIA), is more popularly called simply RS-232, where RS stands for \\\"recommended standard.\\\" Although this RS prefix has been replaced in recent years with EIA/TIA to help identify the source of the standard, this paper uses the common RS-232 notation.
The official name of the EIA/TIA-232-E standard is \"Interface Between Data Terminal Equipment and Data Circuit-Termination Equipment Employing Serial Binary Data Interchange.\" Although the name may sound intimidating, the standard is simply concerned with serial data communication between a host system (Data Terminal Equipment, or DTE) and a peripheral system (Data Circuit-Terminating Equipment, or DCE).
The RS-232 standard also limits the maximum slew rate at the driver output. This limitation was included to help reduce the likelihood of crosstalk between adjacent signals. The slower the rise and fall time, the less chance of crosstalk. With this in mind, the maximum slew rate allowed is 30V/ms. Additionally, standard defines a maximum data rate of 20kbps , again to reduce the chance of crosstalk.
Because RS-232 is a complete standard, it includes more than just specifications on electrical characteristics. The standard also addresses the functional characteristics of the interface, #2 on our list above. This essentially means that RS-232 defines the function of the different signals used in the interface. These signals are divided into four different categories: common, data, control, and timing. See Table 2. The standard provides abundant control signals and supports a primary and secondary communications channel. Fortunately few applications, if any, require all these defined signals. For example, only eight signals are used for a typical modem. Examples of how the RS-232 standard is used in real-world applications are discussed later. The complete list of defined signals is included here as a reference. Reviewing the functionality of all these signals is, however, beyond the scope of this paper.
Moving beyond the EIA-232 specification is megabaud mode, which allows the driver slew rate to increase, thereby providing data rates up to 1Mbps. MegaBaud mode is useful for communication between high-speed peripherals such DSL or ISDN modems over short distances.
The charge pumps of Maxim RS-232 transceivers rely on capacitors to convert and store energy, so choosing these capacitors affects the circuit's overall performance. Although some data sheets indicate polarized capacitors in their typical application circuits, this information is shown only for a customer who wants to use polarized capacitors. In practice, ceramic capacitors work best for most Maxim RS-232 ICs.
The UART performs the \"overhead\" tasks necessary for asynchronous serial communication. Asynchronous communication usually requires, for example, that the host system initiate start and stop bits to indicate to the peripheral system when communication will start and stop. Parity bits are also often employed to ensure that the data sent has not been corrupted. The UART usually generates the start, stop, and parity bits when transmitting data, and can detect communication errors upon receiving data. The UART also functions as the intermediary between byte-wide (parallel) and bit-wide (serial) communication; it converts a byte of data into a serial bit stream for transmitting and converts a serial bit stream into a byte of data when receiving.
Now that an elementary explanation of the TTL/CMOS to RS-232 interface has been provided, we can consider some real-world RS-232 applications. It has already been noted in the Functional Characteristics section above that RS-232 applications rarely follow the RS-232 standard precisely. The unnecessary RS-232 signals are usually omitted. Many applications, such as a modem, require only nine signals (two data signals, six control signals, and ground). Other applications require only five signals (two for data, two for handshaking, and ground), while others require only data signals with no handshake control. We begin our investigation of real-world implementations by considering the typical modem application.
Request to Send (RTS): When the host system (DTE) is ready to transmit data to the peripheral system (DCE), RTS is turned ON. In simplex and duplex systems, this condition maintains the DCE in receive mode. In half-duplex systems, this condition maintains the DCE in receive mode and disables transmit mode. The OFF condition maintains the DCE in transmit mode. After RTS is asserted, the DCE must assert CTS before communication can commence.
Data Terminal Ready (DTR): DTR indicates the readiness of the DTE. This signal is turned ON by the DTE when it is ready to transmit or receive data from the DCE. DTR must be ON before the DCE can assert DSR.
Although the modem application discussed above is simplified from the RS-232 standard because of the number of signals needed, it is still more complex than many system requirements. For many applications, only two data lines and two handshake control lines are necessary to establish and control communication between a host system and a peripheral system. For example, an environmental control system may need to interface with a thermostat using a half-duplex communication scheme. At times the control systems read the temperature from the thermostat and at other times they load temperature trip points to the thermostat. In this type of simple application, only five signals could be needed (two for data, two for handshake control, and ground).
Figure 5 illustrates a simple half-duplex communication interface. As can be seen, data is transferred over the TD (Transmit Data) and RD (Receive Data) pins, and the RTS (Ready to Send) and CTS (Clear to Send) pins provide handshake control. RTS is driven by the DTE to control the direction of data. When it is asserted, the DTE is placed in transmit mode. When RTS is inhibited, the DTE is placed in receive mode. CTS, which is generated by the DCE, controls the flow of data. When asserted, data can flow. However, when CTS is inhibited, the transfer of data is interrupted. The transmission of data is halted until CTS is reasserted.
Another limitation in the RS-232 standard is the maximum data rate. The standard defines a maximum data rate of 20kbps, which is unnecessarily slow for many of today's applications. RS-232 products manufactured by Dallas Semiconductor guarantee up to 250kbps and typically can communicate up to 350kbps. While providing a communication rate at this frequency, the devices still maintain a maximum 30V/ms maximum slew rate to reduce the likelihood of crosstalk between adjacent signals.
SERDES (serializer-deserializer) data processing rates vary widely. At the low end, SERDES systems are used in car rear-view camera systems, where the data rate is usually less than 1 Gbps. At the high end, they are used in high-bandwidth Internet optical routers, where the data rate is 10 Gbps or more.
SERDES designers use SPICE simulators, which are accurate but computationally intensive. As a result, simulating SERDES devices running at data rates above 10 Gbps using a SPICE simulator is extremely time-consuming, limiting opportunities for design exploration and increasing the cost of design errors.To speed up simulation, designers are turning to a much faster approach: top-down design. Top-down design uses a behavioral model to rapidly simulate system performance. Designers can quickly evaluate design alternatives, and use SPICE simulation to test only the best-performing design.
Why SERDES Some communications systems send data serially across channels, for example, Internet data sent along fiber-optic cables and car rear-view camera data sent along twisted-pair wires. Because electronic systems process data in parallel, these systems need a way to convert from serial to parallel, and vice versa. This is the job of the SERDES system (Figure 1 ).
Data transmission and channel modeling Because we need our system to work with a specific backplane