A multi piston machine includes a rotor, pistons, a first control valve, and a second control valve. The pistons abut against a cam surface with multiple lobes. The machine is switchable between at least three non-zero displacement volumes using the first and the second control valves. The first control valve is connected to a first and a third fluid chamber. The second control valve is connected to a second and a fourth fluid chamber. The first and the second control valve are connected to first and the second working port respectively. A third number of second control openings is twice a second number of the lobes. There is a first and a second group of the second control openings. Adjacent second control openings belong to a different first or second group. The second control openings of the first group are either connected to the first or the second fluid chamber.

A hydrostatic rotating machine includes an internal element and an external element that revolve with respect to one another about an axis of rotation, a cylinder block, and a hydraulic distributor. The hydraulic distributor includes an insertion section extending axially between a section of lesser diameter and a section of greater diameter, with a first synchronization surface, and fluid distribution ducts which each have an end segment opening transversely at the first synchronization surface, and obliquely with respect to the axis of rotation. The cylinder block includes a reception section complementing the insertion section of the hydraulic distributor, and fluid diffusion ducts which each have an end segment opening transversely at the second synchronization surface, and obliquely with respect to the axis of rotation.