Siemens UL 489, UL1066 specifications COM16 Supported Function Codes, Function 01 Read Coils

Communication-capable Circuit Breakers

WL Circuit Breaker

Default Communication Parameters

The COM16 comes set-up with the following default Communication Parameters:

Baud: 19,200 Unit ID: 126 Parity: Even

Graphic 3-3

Data formating byte order

Data points larger than two bytes transmitted in the Motorola Format (Big-Endian)

Graphic 3-2
	Byte order			Type of data
	Byte 0	Byte 0		char, unsigned char
	Byte 1	Byte 1
	Byte 0	High byte		signed int, unsigned int
	Byte 1	Low byte
	Byte 0	High byte	High word
	Byte 1	Low byte
				signed long, unsigned long
	Byte 2	High byte	Low word
	Byte 3	Low byte

COM16 Supported Function Codes

Function 01: Read Coils

Function	This function reads the state of multiple Control Bits and Extra Flags in a COM16 slave.
Bit Start Address	Any value from 0000 hex to 000F hex. If any other address is specified, an Exception Code of 02 (Invalid Data
	Address) will be returned.
Quantity of Bits	If “Quantity of Bits” is not in the range of 1 to 16, an Exception Code of 03 (Invalid Data Value) will be returned.
	If an attempt to read a bit beyond Bit Address 000F hex is made, an Exception Code of 02 (Invalid Data Address)
	will be returned.

Function 02: Read Discrete Inputs

Function	This function reads the state of the bits in the Status Register in a COM16 slave.
Bit Start Address	Any value from 0000 hex to 000F hex. If any other address is specified, an Exception Code of 02 (Invalid Data
	Address) will be returned.
Quantity of Bits	If “Quantity of Bits” is not in the range of 1 to 16, an Exception Code of 03 (Invalid Data Value) will be returned.
	If an attempt to read a bit beyond Bit Address 000F hex is made, an Exception Code of 02 (Invalid Data Address)
	will be returned.
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WL MODBUS Communication and Electronic Accessories • January 2005