Description
The Metasys N2 network supports communications with a diverse range of devices. Many N2 compatible devices use their own flavor of the protocol. The different flavors are designed to co-exist on the same N2 network. Care must be taken to ensure the device of interest is covered by the FieldServer implementation.
At present the FieldServer Metasys N2 driver will support communications with the following devices or classes of devices when acting as a client:
- N2Open-compliant devices. N2Open is a published N2-compatible protocol enabling 3rd party device vendors to integrate with N2.
- VMA 1400 series (with restrictions, see below)
- DX9100 and XT9100
When acting as a server the FieldServer Metasys N2 driver can emulate an N2Open device only.
| Fieldserver Mode |
Nodes |
Comments |
| Client |
1 |
Only 1 client node allowed on Multidrop systems. Can communicate with:
- N2Open
- VMA 1400 series (AI,BI,AO,BO and custom types)
- DX9100 / XT9100
|
| Server |
255 |
Number of nodes limited by N2 address space. Can only act as a N2Open server node. |
Formal Driver Type
Connection Information
| Connection type: |
RS-485 (Two wire, Half-Duplex) |
| Baud Rates: |
9600 (N2 standard) |
| Data Bits: |
8 |
| Stop Bits: |
1 |
| Parity: |
None |
| Multidrop Capability: |
Yes |
Devices tested
| Device |
Supported |
Tested (FACTORY, SITE) |
N2Open Device |
| UNT |
 |
Site |
|
| VMA1410, VMA1420 |
|
Factory and Site |
|
| DX9100 with XT9100 extension |
|
Factory and Site |
|
| LCP/DX9100 |
 |
not tested |
|
| NCM (FieldServer as N2Open server) |
|
Factory and Site |
|
| VAV |
|
Site |
|
| AHU |
|
not tested |
|
| VND |
|
not tested |
|
| PHX |
Consult Factory |
not tested |
Consult Factory |
| MIG |
Consult Factory |
not tested |
Consult Factory |
| ILC |
Consult Factory |
not tested |
Consult Factory |
| IFC |
Consult Factory |
not tested |
Consult Factory |
| TC-9100 |
Consult Factory |
not tested |
Consult Factory |
| TEC1000 |
Consult Factory |
not tested |
Consult Factory |
Connection configurations
Connection Notes
Only one N2 client may be connected to a N2 network. If the FieldServer is to act as a client, ensure no other clients are connected to the same N2 network. In the Interceptor Mode the FieldServer can be installed between an existing N2 host and the remainder of the N2 network. It will then intercept the data, and is also able to interleave its own polls for data items not configured in the host in the time between polls sent by the host
Communications functions - Supported functions at a glance:
Function Codes Supported - N2Open:
| FieldServer Data Type |
Description (or Device Data Type) |
| Analog_Input |
Analog Input (AI) |
| Digital_Input |
Binary Input (BI) |
| Analog_Output |
Analog Output (AO) |
| Digital_Output |
Binary Output (BO) |
| Float_Reg |
Internal Float value (ADF) |
| Integer |
Internal Integer value (ADI) |
| Byte |
Internal Byte value (BD) |
Read Operations Supported - N2Open
| FieldServer as a Client |
FieldServer as a Server |
| Read Current Value (all data types) |
Read Current Value (all data types) |
| direct read, Change-of-State (COS) poll |
direct read, Change-of-State (COS) poll |
| Read Attribute (all data types): |
Read Attribute (all data types): |
| direct read, specifying a legal attribute number |
direct read, specifying a legal attribute number direct read, specifying a legal attribute number |
| |
Identify Self command |
Write (Control) Operations Supported - N2Open
| FieldServer as a Client |
FieldServer as a Server |
| Override Current Value (all data types) implemented as Write on FieldServer |
Override Current Value (all data types) implemented as Write on FieldServer |
| Override Release (all data types) |
Override Release (all data types) |
| Write Attribute (all data types) direct write, specifying a legal attribute number |
Write Attribute (all data types) direct write, specifying a legal attribute number |
Listing of Supported Attributes - N2Open
| Data Type |
Attribute No. |
Attribute |
| Analog Input |
1 |
Object Configuration |
| 2 |
Object Status |
| 3 |
Analog Input Value |
| 4 |
Low Alarm Limit |
| 5 |
High Alarm Limit |
| 6 |
Low Warn Limit |
| 7 |
High Warn Limit |
| 8 |
Differential |
| Binary Input |
1 |
Object Configuration |
| 2 |
Object Status |
| Analog Output |
1 |
Object Configuration |
| 2 |
Object Status |
| 3 |
Current Value |
| Binary Output |
1 |
Object Configuration |
| 2 |
Object Status |
| 3 |
Minimum On-Time |
| 4 |
Minimum Off-Time |
| 5 |
Maximum Cycles/Hour |
| Internal Float |
1 |
Object Status |
| 2 |
Current Value |
| Internal Integer |
1 |
Object Status |
| 2 |
Current Value |
| Internal Byte |
1 |
Object Status |
| 2 |
Current Value |
Unsupported Functions and Data Types - N2Open
| Function |
Reason |
| Time Update |
Not required |
| Read Memory Diagnostics |
Not required |
| Warm Start Message |
Not required |
| Status Update Message |
Not required |
| Programming messages (upload, download) |
FieldServer is a data transfer device, and as such, programming messages are not required |
Data Types Supported - VMA
| FieldServer Data Type |
Description (or Device Data Type) |
| Analog_Input |
Analog Input (AI) |
| Digital_Input |
Binary Input (BI) |
| Analog_Output |
Analog Output (AO) |
| Digital_Output |
Binary Output (BO) |
| Float_Reg |
Internal Float value (ADF) |
| Integer |
Internal Integer value (ADI) |
| Byte |
Internal Byte value (BD) |
Read Operations Supported - VMA
| FieldServer as a Client |
FieldServer as a Server |
| Read Current Value (all data types) |
Not applicable |
| Direct Read, Change-of-State (COS) poll |
Write (control) Operations Supported - VMA
| FieldServer as a Client |
FieldServer as a Server |
| Write / Override Current Value (all data types) implemented as Write on FieldServer |
Not applicable |
| Override Release (AI and BI only) use writes for outputs and internal values |
Unsupported Functions and Data Types - VMA
| Function |
Reason |
| Programming messages (upload, download) |
FieldServer is a data transfer device, and as such, programming messages are not required. Note that the Interceptor Mode will not allow the field devices to be programmed through the FieldServer. |
Data Types Supported - DX9100
| FieldServer Data Type |
Description (or Device Data Type) |
| Not specified for DX9100 device type |
Supported sections of Address Map: |
| general control module |
| programmable modules 1-12 |
| analog input modules 1-8 |
| analog output modules 1-2 |
| digital output modules 3-8 |
| extension modules 1-8 |
| time schedules 1-8 |
| optimal start/stop modules 1-2 |
| analog output modules 9-10 |
| auxiliary analog output modules 11-13 |
Read Operations Supported - DX9100
| FieldServer as a Client |
FieldServer as a Server |
| Read of all points supported |
Not applicable |
Write (control) Operations Supported - DX9100
| FieldServer as a Client |
FieldServer as a Server |
| Write of all points supported |
Not applicable |
| DX9100 may not allow writes to specific values |
Unsupported Functions and Data Types - DX9100
| Function |
Reason |
| Programming messages |
FieldServer is a data transfer device, and as such, programming messages are not required |
