Data Type Mapping
The following table maps the data types that DeviceHub offers to those OPC UA servers recognizes at the exposed data points.
DeviceHub Data Type | OPC UA Data Type |
|---|---|
bin | Boolean |
bit | Boolean |
bool | Boolean |
int8 | SByte |
sint | SByte |
uint8 | Byte |
usint | Byte |
byte | Byte |
int | Int16 |
int16 | Int16 |
ENUM16 | UInt16 |
bcd | UInt16 |
uint | UInt16 |
uint16 | UInt16 |
word | UInt16 |
dint | Int32 |
int32 | Int32 |
dbcd | UInt32 |
dword | UInt32 |
udint | UInt32 |
uint32 | UInt32 |
int64 | Int64 |
lint | Int64 |
lbcd | UInt32 |
lword | UInt64 |
uint64 | UInt64 |
ulint | UInt64 |
FL | Float |
flt32 | Float |
float | Float |
float32 | Float |
real | Float |
double | Double |
dreal | Double |
flt64 | Double |
float64 | Double |
lreal | Double |
number | Double |
AC3 | String |
AC7 | String |
AC10 | String |
AC12 | String |
AC20 | String |
AC30 | String |
AC40 | String |
ATTRIBUTE | String |
auto | String |
char | String |
custom | String |
date | String |
decimal | String |
DNP3TIME | String |
dt | String |
dtl | String |
DT6 | String |
hex | String |
json | String |
ldt | String |
ltime | String |
ltod | String |
ostr | String |
range | String |
s5time | String |
single | String |
str | String |
string | String |
tlp | String |
time | String |
tod | String |
UC10 | String |
UC20 | String |
UC30 | String |
UC40 | String |
wchar | String |
wstring | String |
If a device driver supports count, OPC UA needs to have an array for the corresponding data type where the array size equals the count value.
Counters and timers are defined as separate structs or data types in most PLCs. Typically, the edge device is used to read the counter.acc or timer.acc values. These values are likely to be of dint or udint type and should be mapped accordingly.
For example, if DeviceHub has a tag with data type bool and count 10, OPC UA must have data type defined as ArrayOfBoolean[10].