AR-B1375/AR-B1376 User s Guide

11. PROGRAMMING RS-485 & INDEX

11.1 PROGRAMMING RS-485

The majority communicative operation of the RS-485 is in the same of the RS-232. When the RS-485 proceeds the transmission which needs control the TXC signal, and the installing steps are as follows:

Step 1: Enable TXC

Step 2: Send out data

Step 3: Waiting for data empty

Step 4: Disable TXC

NOTE: Please refer to the section of the “Serial Port” in the chapter “System Control” for the detail description of the COM port’s register.

(1) Initialize COM port

Step 1: Initialize COM port in the receiver interrupt mode, and /or transmitter interrupt mode. (All of the communication protocol buses of the RS-485 are in the same.)

Step 2: Disable TXC (transmitter control), the bit 0 of the address of offset+4 just sets “0”.

NOTE: Control the AR-B1375/AR-B1376 CPU card’s DTR signal to the RS-485’s TXC communication.

(2) Send out one character (Transmit)

Step 1: Enable TXC signal, and the bit 0 of the address of offset+4 just sets “1”.

Step 2: Send out the data. (Write this character to the offset+0 of the current COM port address)

Step 3: Wait for the buffer’s data empty. Check transmitter holding register (THRE, bit 5 of the address of offset+5), and transmitter shift register (TSRE, bit 6 of the address of offset+5) are all sets must be “0”.

Step 4: Disabled TXC signal, and the bit 0 of the address of offset+4 sets “0”

(3) Send out one block data (Transmit – the data more than two characters)

Step 1: Enable TXC signal, and the bit 0 of the address of offset+4 just sets “1”.

Step 2: Send out the data. (Write all data to the offset+0 of the current COM port address)

Step 3: Wait for the buffer’s data empty. Check transmitter holding register (THRE, bit 5 of the address of offset+5), and transmitter shift register (TSRE, bit 6 of the address of offset+5) are all sets must be “0”.

Step 4: Disabled TXC signal, and the bit 0 of the address of offset+4 sets “0”

(4) Receive data

The RS-485’s operation of receiving data is in the same of the RS-232’s.

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Toshiba AR-B1375, AR-B1376 Programming RS-485 & Index, Initialize COM port, Send out one character Transmit, Receive data

386SX, AR-B1376, AR-B1375 specifications

The Toshiba AR-B1375 and AR-B1376 are notable embedded computing solutions that incorporate the 386SX microprocessor architecture. Designed for various applications, these models focus on reliability, performance, and versatility, making them appealing choices for system integrators and developers.

At the core of the AR-B1375 and AR-B1376 is the Intel 386SX microprocessor. This landmark processor marked a significant advancement in computing technology, introducing a 32-bit architecture while maintaining compatibility with 16-bit applications. The 386SX is known for its efficient processing capabilities, offering both multitasking support and enhanced memory management. It operates at clock speeds ranging typically from 16 MHz to 25 MHz, contributing to its effectiveness in running industrial applications.

One of the key features of the AR-B1375 and AR-B1376 systems is their modular architecture, which allows for easy customization and expansion. This modularity means users can tailor the hardware according to specific requirements, making it suitable for a wide range of applications such as automation, telecommunications, and embedded systems.

Both models support various I/O options, ensuring seamless integration with peripherals and external devices. They typically come equipped with serial and parallel ports, as well as support for modern interfaces like USB. The systems also feature onboard expansion slots, enabling the addition of further functionality, such as additional memory or specialized processing units.

In terms of memory, the AR-B1375 and AR-B1376 support a range of RAM configurations, allowing users to scale their systems based on the application demands. The inclusion of EPROM and EEPROM options also facilitates easy updates and programmability, which is crucial for embedded systems that often require firmware adjustments over time.

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To summarize, the Toshiba AR-B1375 and AR-B1376, coupled with the 386SX microprocessor, offer a blend of performance, flexibility, and reliability. Their modular design, extensive I/O support, and memory scalability make them ideal for a variety of embedded computing applications, placing them as commendable options in the world of industrial computing solutions. These systems not only exemplify Toshiba's commitment to innovation but also contribute significantly to the functionality of embedded technologies in a rapidly evolving industry.