Message formats
| The data area of SSI messages has the following general structure (the specific structure is dealt with under the individual messages): |
| length | Parameter |
| 2 bytes | Length specifying the number of subsequent bytes in this message. |
| 1 byte | The SSI ID (equals 21H for all SSI messages) |
| 5 bytes | Source address (comprising region number, component number, module, value number, subaddress, each 1 byte) |
| 2 bytes | Message status bits (see 3.2) |
| 2 bytes | Data status bits (see 3.3) |
| 1 byte | Data format (message type) |
| 1 byte | Data type (there is a data-type/data-format assignment table for each project) |
| A list of the SSI message types supported by the driver follows. Most message types can be set in both the message and the command direction. Different peripheral addresses must be specified for the message and command direction. |
