143 • HRVS-DN Communication (ModBus Protocol)
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byte 10: CRC_Low
($XX)
byte 11: CRC_High
($XX)
The HRVS-DN normal response:
byte 1: Serial Link No.
($0B)
byte 2: Function
($10)
byte 3: Starting Address High
($02)
byte 4: Starting Address Low
($F0)
byte 5: No. of Registers High
($00)
byte 6: No. of Registers Low
($01)
byte 7: CRC_Low
($XX)
byte
8:
CRC_High
($XX)
16.10
Discrete Commands (Coils, 0x References)
The HRVS-DN incorporates 16 "Coils", (bit parameters), from which only 3 are operative. The other 13 are
reserved and were incorporated to enable the user to use word (16 bits) type parameters. Coil # is 1"1
based". The actual address is 1 lower than coil #. For example coil #1 is addressed as 0 (00000). Use
functions 5 or 15 to send control commands to the starter.
The coils have the following
0x
references:
Coil #
Coil Address
Use in HRVS-DN
Comment
1
0
Reserved.
2
1
Reserved.
3
2
Reserved.
4
3
Start/Stop Relay
Write "1" (ON) to Start / Run.
Write "0" (OFF) to Stop.
5
4
Dual Adjust
Write "1" (ON) to turn On.
Write "0" (OFF) to turn Off.
6
5
Reserved.
7
6
Reserved.
8
7
Reset
Write "1" (ON) momentarily to Reset.
Rejected, if given together with Start command.
9..16 8..15
Reserved
Example 6 - Read Coils:
To read coils 1..8 status of HRVS-DN # 10, the host computer sends the following Query frame:
byte 1: Serial Link No.
($0A)
byte 2: Function
($01)
byte 3: Starting Address High
($00)
byte 4: Starting Address Low
($00)
byte 5: No. of Coils High
($00)
byte 6: No. of Coils Low
($08)
byte 7: CRC_Low
($XX)
byte 8: CRC_High
($XX)
The HRVS-DN response, when coils 7..0 are OFF OFF OFF ON OFF ON OFF OFF:
byte 1: Serial Link No.
($0A)
byte 2: Function
($01)
byte 3: Byte Count
($01)
byte 4: Data (coils 7..0)
($14)
byte 5: CRC_Low
($XX)
byte
6:
CRC_High
($XX)
Example 7 - Force Single Coil:
To start the motor controlled by HRVS-DN # 1, the host computer writes "1" to the "START/STOP COIL" (coil
4 addressed as 3) .
