Chapter 8 MODBUS CommunicationsASDA-B Series

CRC (RTU Mode):

CRC (Cyclical Redundancy Check) is calculated by the following steps:

Step 1: Load a 16-bit register (called CRC register) with FFFFH.

Step 2: Exclusive OR the first 8-bit byte of the command message with the low order byte of the 16-bit CRC register, putting the result in the CRC register.

Step 3: Extract and examine the LSB. If the LSB of CRC register is 0, shift the CRC register one bit to the right. If the LSB of CRC register is 1, shift the CRC register one bit to the right, then Exclusive OR the CRC register with the polynomial value A001H.

Step 4: Repeat step 3 until eight shifts have been performed. When this is done, a complete 8-bit byte will have been processed, then perform step 5.

Step 5: Repeat step 2 to step 4 for the next 8-bit byte of the command message.

Continue doing this until all bytes have been processed. The final contents of the CRC register are the CRC value.

NOTE

1)When transmitting the CRC value in the message, the upper and lower bytes of the CRC value must be swapped, i.e. the lower order byte will be transmitted first.

2)For example, reading 2 words from address 0101H of the AC servo drive with address 01H. The final content of the CRC register from ADR to last data character is 3794H, then the command message is shown as follows. What should be noticed is that 94H have to be transmitted before 37H.

Command Message

ADR

01H

CMD

03H

Starting data address

01H (Upper byte)

 

01H (Lower bytes)

 

Number of data

00H (Upper bytes)

(Count by word)

02H (Lower bytes)

CRC Check Low

94H (Lower bytes)

CRC Check High

37H (Upper bytes)

 

 

End1, End0 (Communication End)

ASCII Mode:

In ASCII mode, (0DH) stands for character ’\r’ (carriage return) and (0AH) stands for character ’\n’ (new line), they indicate communication end.

RTU Mode:

In RTU mode, a silent interval of more than 10ms indicates communication end.

Revision January 2009

8-13

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Delta Electronics ASDA-B Series manual CRC RTU Mode, End1, End0 Communication End Ascii Mode

ASDA-B Series specifications

Delta Electronics, a global leader in power and thermal management solutions, has made significant strides in the automation and control sectors with its ASDA-B Series of servo drives. This series is engineered for precision motion control applications and is ideal for various industries, including manufacturing, robotics, and packaging.

One of the standout features of the ASDA-B Series is its advanced control algorithms. The series utilizes a high-performance digital signal processor (DSP) that enables precise control of servo motors, resulting in exceptional responsiveness and stability even at high speeds. This technology is particularly beneficial in applications requiring quick acceleration and deceleration, ensuring optimal performance in dynamic environments.

The ASDA-B Series offers a wide range of power ratings, making it versatile enough to cater to different motor sizes and application requirements. It supports various feedback devices, including encoders and resolver systems, enhancing its adaptability and accuracy in diverse operational contexts. The series also features a user-friendly interface, allowing for easy programming and setup, thus minimizing downtime and maximizing productivity.

One of the notable characteristics of the ASDA-B Series is its compact design. The small form factor not only saves valuable space in control cabinets but also simplifies installation and maintenance processes. Additionally, the series is built to withstand tough industrial environments, featuring robust construction that enhances durability and reliability.

Another key technology integrated into the ASDA-B Series is its advanced communication capabilities. The drives support multiple industrial communication protocols, including Ethernet/IP, CANopen, and Modbus, allowing for seamless integration into existing network systems. This connectivity is crucial for applications that require real-time data exchange and remote monitoring.

To ensure energy efficiency, Delta Electronics has incorporated innovative energy-saving technologies in the ASDA-B Series. These technologies optimize power consumption during operation, resulting in lower energy costs and reduced carbon footprint. Moreover, the thermal management features ensure that the drives operate within safe temperature ranges, enhancing their longevity and performance reliability.

In conclusion, Delta Electronics' ASDA-B Series servo drives represent a powerful solution for modern automation needs. With their advanced control algorithms, compact design, versatile communication options, and energy-saving technologies, these drives cater to a wide array of industrial applications, reinforcing Delta's commitment to innovation and efficiency in the automation landscape.