IODD 101 (Tutorial)
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iqMAXREFDES23 Demo Board
Maxim's Santa Cruz (MAXREFDES23#) reference design is the world's smallest IO-Link® light sensor compliant with IEC 61131-9. The entire design fits onto a 6.5mm x 25mm printed circuit board (PCB).
Sensor simple logic
In iqMAXREFDES23 have been implemented simple switch-point hysteresis logic and additionally can be configured as normally open (NO) or normally closed (NC).
By default light switch-point settings (255 is the maximal value):
| What | SP (Level) | Hysteresis | Mode |
|---|---|---|---|
| Light intensity | 128 (0x80) | 16 (0x10) | Normally Open (NO) |
| Darkness control | 16 (0x10) | 4 (0x04) | Normally Closed (NC) |
IODD Introduction
An IODD (IO Device Description) is a set of files that formally describes an IO-Link Device. An IODD is mandatory for each IO-Link Device.
The IODD is created by the device vendor and shall be sufficient for IO-Link Tools to identify, communicate, parameterize and diagnose the device.
The file name shall follow the following rule:
<vendor name>-<device name>-<date of file creation>-IODD<schema version>.xml
for iqMAXREFDES23 it's correspond for:
For more IODDs look at IODD Samples.
IODD basic concepts
Datatype
Actually, the data types form the following hierarchy:
For example (BooleanT with enums):
...
Process Data
- Byte (MSB): Light intensity (from 0 to 255).
- Byte (LSB): [.......F - light intensity switch-point flag (1bit)].
...
Y
Variables
| IO-Link index | Mode | Description | Default value |
|---|---|---|---|
| 256 (0x0100) | read/write | Ambient light switch-point level | 128 (0x80) |
| 257 (0x0101) | read/write | Ambient light switch-point hysteresis | 16 (0x10) |
...
Y
Events
...
Y
