Multilin SR469 - Page 154

SUPPORTED MODBUS FUNCTIONS 6. COMMUNICATIONS
6-6
Function 02:
EX1: Request slave 11 to respond with status of digital inputs 5 to 9:
Digital Input
Status
D1: Access Closed
D2: Test Open
D3: Starter Status Open
D4: Emergency Restart Open
D5: Remote Reset Closed
D6: Assignable Input1 Closed
D7: Assignable Input2 Closed
D8: Assignable Input3 Open
D9: Assignable Input4 Closed
Bit Mask(LSB) 0111 0001
Bit Mask(MSB) 0000 0001
Master Transmission Bytes Example (hex)
SLAVE ADDRESS 1 0B message for slave 11
FUNCTION CODE 1 02 read digital input status
STARTING RELAY COIL 2 00 starting at digital input 5
05
NUMBER OF RELAYS 2 00 5 DI (i.e. D5, D6, D7, D8, D9)
05
CRC 2 A8 CRC calculated by the master
A2
Slave Response
SLAVE ADDRESS 1 0B message from slave 11
FUNCTION CODE 1 02 read digital input status
BYTE COUNT 1 02 2 byte bit masks
BIT MASK (LSB) 1 71 bit mask of requested DI
BIT MASK (MSB) 1 01
CRC 2 C5 CRC calculated by the slave
B9
EX2: Request slave 11 to respond with status of digital inputs 1 to 4:
Digital Input
Status
D1: Access Closed
D2: Test Open
D3: Starter Status Open
D4: Emergency Restart Open
D5: Remote Reset Closed
D6: Assignable Input1 Closed
D7: Assignable Input2 Closed
D8: Assignable Input3 Open
D9: Assignable Input4 Closed
Bit Mask(LSB) 0111 0001
Master Transmission Bytes Example (hex)
SLAVE ADDRESS 1 0B message for slave 11
FUNCTION CODE 1 02 read digital input status
STARTING RELAY COIL 2 00 starting at digital input 5
01
NUMBER OF RELAYS 2 00 5 DI (i.e. D5, D6, D7, D8, D9)
04
CRC 2 28 CRC calculated by the master
A3
Slave Response
SLAVE ADDRESS 1 0B message from slave 11
FUNCTION CODE 1 02 read digital input status
BYTE COUNT 1 01 1 byte bit masks
BIT MASK 1 01 bit mask of requested DI
CRC 2 63 CRC calculated by the slave
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