PHILIP REES MDS MIDI TO DIN SYNC CONVERTER

Ports provided The MDS has a MIDI In port, for which a handy MIDI Thru socket is provided. The MDS has a single Sync24 Sync Out socket. The signals have good drive capability, and we have not found any Sync interface applications compatibility problems. The Sync24 output In the diagram above, a normal MIDI cable is able to drive several Sync24 inputs in connects the MIDI Out socket of the parallel. To make use of this you will computer to the MIDI IN of the MDS. The probably need a special multi-drop cable computer has been set to run off its own internal clock. Also, MIDI Timing Clocks Out Synchro systems has been enabled in the computer sequencer When pieces of music technology equip- program. The beat lamp should be flashing, ment are required to work together, a which indicates that the MDS is receiving a means may be required synchronise them. stream of MIDI clocks from the computer. assembly. Some Sync24 devices, notably The MIDI standard includes a group of the Roland MC-202, have a built-in fan-out The MIDI THRU output of the MDS is single-byte messages called System Real capability (like a Sync24 thru) to drive extra connected to the MIDI In on the sythesiser. Time (SRT), four of which are concerned The SYNC OUT port of the MDS is linked to Sync slave units - see adjacent with synchronisation (Clock, Start, Continue MDS diagram. the Sync port of the old drum machine, and Stop). Out which should be set to Input mode.

The Sync24 system was introduced by the t t When the sequencer is running, the u u n I computer will transmit Channel Voice and

estimable Japanese company, Roland. It O O was subsequently adopted by a few other SRT messages. These arrive at the MIDI IN manufacturers, but was then largely port of the MDS, and are duplicated at the superseded by the sync facilities of MIDI. MIDI THRU port. When the Channel Voice Sync24 is popularly known as ‘DIN Sync’, messages arrive at the synthesizer they are because it uses the round five pin rendered as musical notes. The synth DIN connector, coinciden- ignores the SRT messages. tally the same as is The sync converter ignores the Channel used for MIDI. Voice messages, but it uses the System Sync In Sync In Real Time messages to derive the Sync24 ANALOGUE signals. These signals go forward to the analogue drum machine, so that it plays in Clock Run DRUM M/C 3 1 time with the master sequencer. 5 Continue The MIDI lead between the Out on the synth 2 4 Continue facility included and the In on the computer makes possible SCREEN As well as regular Start and Stop com- the recording of new sequencer tracks. mands, MDS implements the MIDI Continue command and the corresponding Sync24 feature. Compatible Sync24 devices, such The as the MC-4, should resume correctly when DRUM MACHINE Sync 24 connection synchronised via the MDS. cannot be made with a plain MIDI Out MIDI cable, as shown in the diagram above, Some devices, including the otherwise it requires a pin-to-pin cable with pins 1, 2, 3 wonderful Roland MC-202, respond to a MIDI In Continue by resuming from the beginning of MDS and 5 connected. Although they use the Sync Out same type of connector, you should never the current ‘measure’. You may be able to In the simple connect MIDI sockets to Sync24 sockets. arrange that your master MIDI sequencer example Sync In always restarts from the beginning of a shown here, the Clever converter measure. You can probably manually set Microcomposer is Clock Clock Clock Clock Clock both sequencers to start at the same synchronised to MIDI measure. Alternatively you could always to the MIDI-equipped messages restart the sequence from the top. drum machine via the . Sync24 Clock The Continue facility is not included on MDS some Sync24 devices, notably the Roland TB-303 and TR606. When it is omitted, the Gorgeous wee lamps Continue command will cause the slave to The ‘POWER’ lamp is lit when mains power start the sequence from the very beginning. The Philip Rees MDS MIDI to Sync24 is connected to the MDS. Converter listens to an incoming MIDI SRT Start Stop Continue Stop MIDI The funky `BEAT' lamp (on the front panel, clock stream and generates a corresponding messages Sync24 (DIN sync") format output. The MDS next to the SYNC OUT socket) flashes on and off in time with the sync stream.The appears as a tempo slave to your MIDI Run system, and is a tempo master in Sync24. Sync24 lamp is lit for the first quaver-period of every crotchet-period. It will flash four times during When you have installed your sync converter, Continue 4 your Sync24 device(s) should start, play in a normal common time ( 4) measure. time, and stop automatically, by remote TIME (not to scale) The case is 109mm x 109mm x 40mm. It control from your MIDI master equipment. contains an integral mains power supply.