Control systems and the trigger of a spectrometer built with microstri
p silicon detectors are described. The operation of 16-bit nanosecond
units as fast selectors of events in high-energy experiments is discus
sed. Activating the first-level trigger is by the impact of a beam par
ticle against the target proved to be effective. The decision is taken
within the 400 nsec the particle takes to arrive at the target.