The MIDI sequencer supports the following set of commands.
| String form | Message form |
| break | MCI_BREAK |
| capability | MCI_GETDEVCAPS |
| close | MCI_CLOSE |
| info | MCI_INFO |
| open | MCI_OPEN |
| pause | MCI_PAUSE |
| play | MCI_PLAY |
| record | MCI_RECORD |
| resume | MCI_RESUME |
| save | MCI_SAVE |
| seek | MCI_SEEK |
| set | MCI_SET |
| status | MCI_STATUS |
| stop | MCI_STOP |
| sysinfo | MCI_SYSINFO |