SMC Networks HECR Series Communications Manual page 5

CONTENTS
1 Preparation for Communication ................................................................................................. 1-1
2 Specifications of Communication Method .................................................................................. 2-1
3 Communication Format (same as current HEC series) .............................................................. 3-1
3.1 Control code used for communication ................................................................................. 3-1
3.2 Command code list ............................................................................................................. 3-1
3.3 Communication procedures and format .............................................................................. 3-2
3.4 Calculation of Check Sum ................................................................................................... 3-4
4 Details of Communication Format .............................................................................................. 4-1
4.1 Temperature setting (without writing FRAM) ....................................................................... 4-1
4.2 Reading setting temperature ............................................................................................... 4-1
4.3 Reading internal sensor ...................................................................................................... 4-2
4.4 Reading external sensor ..................................................................................................... 4-3
4.5 Reading alarm status .......................................................................................................... 4-3
4.6 Offset setting (without writing FRAM) .................................................................................. 4-5
4.7 Reading offset .................................................................................................................... 4-5
4.8 Temperature setting (with writing FRAM) ............................................................................ 4-6
4.9 Offset setting (with writing FRAM) ....................................................................................... 4-7
4.10 Communication Format and Examples of Answers from Thermo-con ................................. 4-8
5 MODBUS communication function ............................................................................................. 5-1
5.1 Precautions for communication ........................................................................................... 5-1
5.2 Communication specification .............................................................................................. 5-2
5.3 Setting and checking .......................................................................................................... 5-2
5.4 Communication sequence .................................................................................................. 5-4
5.5 Message configuration ........................................................................................................ 5-5
5.6 Function codes ................................................................................................................... 5-7
5.7 LRC .................................................................................................................................... 5-7
5.8 Explanation of function codes ............................................................................................. 5-8
5.9 Negative response ............................................................................................................ 5-12
5.10 Register Map .................................................................................................................... 5-13
5.11 Communication Format and Examples of Answers from Thermo-con ............................... 5-16
6 Troubleshooting ......................................................................................................................... 6-1