OPC to DDE/SuiteLink Conversions
- Last UpdatedAug 19, 2024
- 1 minute read
When the Gateway Communication Driver receives (writes) data from an OPC client and sends it to a DDE/SuiteLink data source, it converts OPC types to DDE/SuiteLink types as follows:
|
OPC Variant Type |
DDE/SuiteLink Type |
Comments |
|
VT_EMPTY |
Not supported |
Reject write. |
|
VT_NULL |
Not supported |
Reject write. |
|
VT_I2 |
Integer |
|
|
VT_I4 |
Integer |
|
|
VT_R4 |
Real |
|
|
VT_R8 |
Real |
On writes, rejected if out of range. |
|
VT_CY |
String |
|
|
VT_DATE |
String |
|
|
VT_BSTR |
String |
On writes, rejected if out of range. |
|
VT_DISPATCH |
Not supported |
On writes, rejected. |
|
VT_ERROR |
Integer |
|
|
VT_BOOL |
Discrete |
|
|
VT_VARIANT |
Not supported |
On writes, rejected. |
|
VT_DECIMAL |
Float |
On writes, rejected if out of range. |
|
VT_RECORD |
Not supported |
On writes, rejected. |
|
VT_UNKNOWN |
Not supported |
On writes, rejected. |
|
VT_I1 |
Integer |
|
|
VT_UI1 |
Integer |
|
|
VT_UI2 |
Integer |
|
|
VT_UI4 |
Integer |
On writes, rejected if out of range. |
|
VT_INT |
Integer |
|
|
VT_UINT |
Integer |
On writes, rejected if out of range. |
|
VT_VOID |
Not supported |
On writes, rejected. |
|
VT_HRESULT |
Integer |
|
|
VT_PTR |
Not supported |
On writes, rejected. |
|
VT_SAFEARRAY |
Not supported |
Rejects write. On reads, sets quality to Bad. |
|
VT_CARRAY |
Not supported |
Rejects write. |
|
VT_USERDEFINED |
Not supported |
On writes, rejected. |
|
VT_LPSTR |
String |
On writes, rejects if too long. |
|
VT_LPWSTR |
String |
On writes, rejects if too long. |
|
VT_FILETIME |
String |
On writes, rejects if too long. |
|
VT_BLOB |
Not supported |
On writes, rejected. |
|
VT_STREAM |
Not supported |
On writes, rejected. |
|
VT_STORAGE |
Not supported |
On writes, rejected. |
|
VT_STREAMED_OBJECT |
Not supported |
On writes, rejected. |
|
VT_STORED_OBJECT |
Not supported |
On writes, rejected. |
|
VT_BLOB_OBJECT |
Not supported |
On writes, rejected. |
|
VT_CF |
Not supported |
On writes, rejected. |
|
VT_CLSID |
String |
|
|
VT_VECTOR |
Not supported |
On writes, rejected. |
|
VT_ARRAY |
Not supported |
On writes, rejected. |
|
VT_BYREF |
Not supported |
On writes, rejected. |
|
VT_RESERVED |
Not supported |
On writes, rejected. |