View single post by slychiu
 Posted: Tuesday Jan 31st, 2017 01:48 pm
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slychiu



Joined: Saturday Apr 29th, 2006
Location: Singapore
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In Properties, select Modbus Master/Slave as Master





If Modbus Interface is TCP, then the Comfort Server Manager link will be shown



Tabs: Modbus to Comfort, Alarm to Modbus, Monitor Mode can be seen

Modbus to Comfort
This is applicable for UCM/Modbus as Master only, not as Slave.
In this tab, the Modbus addresses are defined and mapped to Comfort registers (Counters, Flags, Sensors, Outputs, Arm Security, Panic, Bypass Zones). Up to 256 Modbus addresses can be mapped to Comfort




 A Typical  Modbus to Comfort screen is shown above. Press Add Modbus Element to add another element




Select the Modbus Element Type from
  • Discrete Input
  • Coil
  • Input Register
  • Holding Register

Discrete Input



Modbus Discrete Inputs are 1 bit (on/off) registers that can be mapped to Counters, Virtual Inputs, Flags, Outputs, Output Toggle, Output Pulse, Arm Security, Panic, Bypass Zone

Coil



Modbus Coils are 1 bit (on/off) registers that can be mapped to Counter, Physical Input, Counter, Flag , Sensor

Input Register



Modbus Input Registers are 16-bit registers that can be mapped to Counters, Sensors, Flags, Outputs, Virtual Inputs, arm security, panic, bypass zone. Modbus Input registers are read only, and cannot be changed by the maped counter and sensor.

Holding Register



Modbus Holding Registers 16-bit registers can be mapped to Counters, Physical Input, Flag, Sensors, Modbus Holding registers are read/write registers and can be changed by the mapped counter and sensor.


Modbus Register Number
After selecting the Modbus element (Coil, Discrete Input, Input Register, Holding Register), enter the Modbus Address in Decimal or Hexadecimal notation (depending on the setting in Properties). Modbus Registers have a range from 0 to FFFF Hexadecimal or 0 to 65535 in Decimal.






Avoid entering the same Register number for the same Modbus element type, eg Coil 1000 is entered in the table it should not be duplicated in any of the tables to avoid conflict. Every Modbus device will have a table showing the Modbus element and address and the function related to  it, so that other Modbus devices acting as Master can read and/or write to the correct Register.

Number of Registers




This means that multiple modbus slave registers can be polled in one command. For example in the above screenshot example on the 1st line, Modbus address 0 Discrete Input  and mapped to Flag 21.  No of Registers = 5 means that  5 sequential Modbus registers are mapped to 5 sequential Flags.
eg
  1. Modbus address 0 -> Flag 21
  2. Modbus address 1 > Flag 22
  3. Modbus address 2 > Flag 23
  4. Modbus Address 3 > Flag 24
  5. Modbus Adress 4 > Flag 25
These modbus addresses must be the same type eg Discrete Inputs
This allows the Modbus Master to poll the slave very fast and reduces the number of Modbus to Comfort Table entries. The above example required 5 entries before, but nopw only requires 1 entry in Modbus to Comfort

Last edited on Sunday Sep 25th, 2022 03:02 am by slychiu

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