machines/vendor/ski780/RS485-780.md

Extracted Tables

Functional Code Data Communication Address

Function Group	Example Address	Description
P0-16	F010H	F0H (P0 group) + 10H (serial no. 16)
AC-08	AC08H	ACH (AC group) + 08H (serial no. 8)
P0-16 No EEPROM	0010H	00H (No EEPROM) + 10H (serial no. 16)
P0-16 EEPROM	F010H	F0H (EEPROM) + 10H (serial no. 16)
AC-08 No EEPROM	4C08H	4CH (No EEPROM) + 08H (serial no. 8)
AC-08 EEPROM	AC08H	ACH (EEPROM) + 08H (serial no. 8)
PF	0xF000 - 0xFEFF	Communication address
A0-AC	0xA000 - 0xACFF	Communication address
U0	0x7000 - 0x70FF	Communication address (read-only)

Parameter Address

Function Group	Address	Description
P-Group	030C	Example for function code P3-12
A-Group	4005	Example for function code A0-05

Status Data

Command Address	Status Function
3000H	1: forward running
	2: reverse running
	3: stop

Digital Output Terminal Control

Command Address	Command Content
2001H	BIT0: DO1 output control
	BIT1: DO2 output control
	BIT2: relay1 output control
	BIT3: relay2 output control
	BIT4: FMR output control
	BIT5: VDO1
	BIT6: VDO2
	BIT7: VDO3
	BIT8: VDO4
	BIT9: VDO5

Analog Output Control

Command Address	Command Content
2002H	0 – 7FFF means 0% - 100%
2003H	0 – 7FFF means 0% - 100%
2004H	0 – 7FFF means 0% - 100%

Fault Description of Frequency Converter

Fault Address	Fault Information
8000H	0000: no fault
	0001: reserve
	0002: overcurrent
	0003: overcurrent during deceleration
	0004: overcurrent during constant speed

Modbus Communication Parameters

Parameter Address	Parameter Description	Data Range
1000H	Communication setting	-10000 – 10000
1010H	PID set
1001H	Running frequency
1011H	PID feedback

Extracted Notes on Modbus

1. SKI780 series frequency converter provides RS485 communication interface and supports Modbus-RTU slave communication protocol. Users can realize centralized control through computer or PLC, set the running command of the frequency converter, modify or read function code parameters, and read working state and fault information .

2. Communication data structure details:

   • Idle slave with a transmission time of more than 3.5 bytes.
   • Slave address (ADR): Range 1-247; 0 is broadcast address.
   • Command codes:
     • 03: read slave parameter
     • 06: write slave parameter .

3. The Modbus protocol for SKI780 inverter only supports the reading or writing of Word parameters, not bytes or bits. The read operation command is 0x03 and the write operation command is 0x06 .

4. Communication setting values, such as the baud rate, data format, and local address, must match between the upper computer and the frequency converter for successful communication. The baud rate range includes 300 BPS to 115200 BPS .

5. CRC verification mode uses the RTU frame format where CRC values are checked to ensure data integrity. CRC (Cyclical Redundancy Check) is applied to all 8-bit bytes in the message, excluding start, stop, and parity bits .

By structuring the documentation in this way, the relevant technical details are clear and accessible for anyone needing to implement or maintain the Modbus communication protocol with SKI780 series frequency converters.