| Direction | Data | Description |
| Tx | ‘??’ | |
| Rx | byte1 byte2 | State (see the description of the State record) ErrCode total number of bytes to receive: 2 bytes (’??’ not echoed!): |
| Direction | Data | Description |
| Tx | ‘??’ | |
| Rx | byte1 byte2 | State (see the description of the State record) ErrCode total number of bytes to receive: 2 bytes (’??’ not echoed!): |