Toshiba VF-AS1 Series, RS485 CRC Generation, Error codes, Bit counter =, End Return CRC

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E6581315

5.2. CRC Generation

“CRC” is a system to check errors in communication frames during data transmission. CRC is composed of two bytes and has hexadecimal-bit binary values. CRC values are generated by the transmission side that adds CRC to messages. The receiving side regenerates CRC of received messages and compares generation results of CRC regeneration with CRC values actually received. If values do not match, data will be aborted.

„Flow

CRC generation ( )

CRC initial data: FFFF

Byte counter n = 0

Nｏ

Byte counter n < Length

Yes

CRC = (CRC XOR nth send byte (0 expanded to word (higher 8 bits))

Bit counter = 0

Bit counter < 8

Nｏ

 

Yes

 

C = (Remainder of CRC ÷ 2)

 

ＣＲＣ >> １

 

Is remainder (C)

Nｏ

 

other than 0?

 

Yes

 

CRC＝

 

(CRC XOR generating polyno-

 

mial (A001))

 

Bit counter +1

 

Byte counter +1

A procedure for generating a CRC is:

1, Load a 16–bit register with FFFF hex (all 1’s). Call this the CRC register.

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

3.Shift the CRC register one bit to the right (toward the LSB), zero–filling the MSB. Extract and examine the LSB.

4.(If the LSB was 0): Repeat Step 3 (another shift).

(If the LSB was 1): Exclusive OR the CRC register with the polynomial value A001 hex (1010 0000 0000 0001).

5.Repeat Steps 3 and 4 until 8 shifts have been per- formed. When this is done, a complete 8–bit byte will have been processed.

6.Repeat Steps 2 through 5 for the next 8–bit byte of the message. Continue doing this until all bytes have been processed.

7.The final contents of the CRC register is the CRC value.

8.When the CRC is placed into the message, its upper and lower bytes must be swapped as described below.

End (Return CRC)

5.3. Error codes

In case of the following errors, the return commands from the inverters are added 80h to the com- mands received by the inverters. The following error codes are used.

Error Code

Description

01

Command error (Returned when a command other than 03 or 06 is received)

02Communication number error (A communication number is not found when Com- mand 03 or 06 is received)

03

Data range error (Data range error when Command 03 or 06 is received

 

Unable to execute (Command 06 is being received and data cannot be written)

04(1) Writing in write-disable-during-operation parameter

(2) Writing in parameter that is executing TYP

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Contents E6581315② Tosvert VF-AS1 Series RS485 Communication FunctionE6581315 Read first Safety precautionsContents General outlines of the communication function BIT15 BIT8BIT7 BIT0Bit Word BIT2 Data transmission specificationsCommunication protocol About the handling of received framesMOUBUS-RTU Toshiba Inverter Protocol Binary mode 2FHData transmission format Data transmission format used in Ascii modeINV-NO CMD Data28H Bytes Checksum area 5bytes BlankData SUM INV-NOData transmission format used in binary mode Returned for the 57H W and 50H P commands Command receivedByte Bytes Sum 1 bytes Checksum not omissible 00H to FFH2FH Byte 4EH6EH Bytes NornTransmission format of Block Communication Page Bytes Blank Start Code INV-NO Dummy data is required for this command CommandsReads the data with the specified communication number Block communication Computer InverterRFE03077BCR RFE03CRPage Transmission errors Format error Data transmission format does not matchCommunication There is no communication number that matches Broadcast communication function VF-AS1 Ascii mode Computer → Inverter Inverter → Computer Examples of the use of communication commandsFrom the computer H = 24d  trip status RFC90CRExamples of Communication programs Next =LENS$ For I=1 to LInput #1,B$ Goto160 T=TIMER COUNT=TIMER-T If Count 0 then T=TIMERPrint #1,B$ Page End If MSComm1.Output = Text2.Text & Chr13 End SubText2.Text = Text1.Text = End Sub Inverter number  MODBUS-RTU protocolRead command MODBUS-RTU transmission formatCRC Blank Command 1 byte Write command5bytes Blank Command 1 byte Text size is 8 bytes fixed InverterCRC Generation Error codesBit counter = End Return CRCInter-drive communication Never use pin-7 P11 QWiring 4-wire RS485 communication） E6581315 QWiring 2-wire RS485 communicationPage Parameters relating to the slave side example =0.01% Proportional control of speed90.00Hz 45.00Hz Slave 100.00Hz 00%Slave 100.00Hz1 00% 80.00Hz 40.00HzINV-NO 1 byte Inverter number Transmission format for inter-drive communication0OFF Communication parametersMODBUS-RTU Inverter number Baud rate,  , Parity PC → INV „ Timer Time-out period Computer linkMaster INV To Slave INV INV → PC PC → INVSend waiting time ,  Free notesUse this function for the following case Communication commands commands from the computer Commands and monitoring from the computerPI OFF OFFForcibly braked Preliminary excitation Electric Power quantityBrake release B Braking answer BAWire RS485 communication FA32 „ FM analog output FA51 „ Terminal board output data FA50„ AM analog output FA52 Output terminal no Specified data outputMonitoring from the computer RFD00CRUnit 0.01% N·m RES „ Input terminal board status FD06, FE06Input terminal function selection 9 f119 BIT15„ Output terminal board status FD07, FE07 ST=ON ST=OFF „ Inverter operating status 1 FD01, FE01„ Inverter operating status 3 FD49, FE49 „ Inverter operating status 2 FD42, FE42„ Inverter operating command mode status FD45, FE45 „ Inverter operating frequency mode status FD46, FE46Preset speed operation „ Alarm information monitor FC91 „ Cumulative operation time alarm monitor FE79Bit Specifications Remarks E6581315 Model Data „ Inverter model capacity code FB05LED setting by communication Parameter Name Range SettingUtilizing panel LEDs and keys by communication „ Block Communication Function for LED Display Blank Ascii LED display data code 00H-1FH are blankKey utilization by communication FA10=0FA10=1 Parameter data ROM EEPPage FE02 Frequency command value 01Hz Alarm codeFE19 Torque command FE29 Input powerTion FE80 Cumulative power on time E6581315 FD50 Light-load high-speed torque 01%FE84 Binary input value option Can Appendix 1 Table of data codesSUB ESCResponse time „ Data transmission time Appendix 2 Response timeVF-A7 Appendix 3 Compatibility with the communication functionAppendix 4 Troubleshooting Appendix 5 Connecting for RS485 communication RXB RXATXA TXB

RS485, VF-AS1 Series specifications

The Toshiba VF-AS1 Series represents a significant advancement in the realm of variable frequency drives (VFDs), designed for various industrial applications that demand precision, efficiency, and reliability. With support for RS485 communication, the VF-AS1 Series fosters seamless integration into complex automation systems, making it the perfect choice for modern manufacturing environments.

One of the standout features of the Toshiba VF-AS1 Series is its versatile communication capabilities. The built-in RS485 port allows for easy connectivity with a range of devices, including PLCs (Programmable Logic Controllers) and HMIs (Human-Machine Interfaces). This ensures real-time monitoring and control of motor functions, enhancing operational efficiency and data analysis.

The VF-AS1 Series is engineered with advanced control technologies that provide exceptional motor performance. It incorporates vector control algorithms that optimize torque and speed regulation for both standard and permanent magnet motors. This results in precise motor control across a wide range of speeds and load conditions, ensuring optimum performance and energy savings.

Another noteworthy characteristic is its user-friendly interface. The VF-AS1 features a clear LCD display that allows for easy navigation and configuration. This intuitive design minimizes the learning curve for operators and technicians, facilitating quick setup and adjustments. Additionally, the series supports various programming options, catering to both novice users and experienced professionals.

Energy efficiency is a key priority in the design of the VF-AS1 Series. The drives are equipped with energy-saving features that help reduce overall power consumption and operational costs. With built-in sleep modes and dynamic energy feedback, these drives optimize energy usage based on demand, making them suitable for both constant and variable load applications.

In terms of safety and protection, the VF-AS1 Series incorporates various built-in safeguards, including overvoltage, undervoltage, and overcurrent protection. This comprehensive approach to safety not only protects the drive itself but also ensures the longevity of connected equipment.

Overall, the Toshiba VF-AS1 Series, with its robust feature set, advanced technologies, and focus on energy efficiency, proves to be a reliable choice for a wide range of industrial applications. Its integration of RS485 communication allows for enhanced connectivity and control, making it an excellent solution for modern automation needs.
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