Bus-capable, modular connection and/or function module for controlling and/or monitoring technical processes and/or for industrial and/or building automation with a plate-like and/or block-like structure, which is designed to be combined with further connection and or function modules to form a connection system, having the following features: a) at least one base terminal carrier for fixing to a mounting base, which has a kind of U-shape, having a base leg 13, on which mounting means, preferably latching means (3, 4) for latching onto a mounting rail, are formed for mounting on the mounting rail, wherein two vertical side legs (14, 15) are integrally formed at the mutually opposite ends of the base leg to the side facing away from the mounting rail, so that a receiving space is formed between the base leg and the side legs, b) at least one electronics housing which can be attached to the base terminal carrier, which is arranged in the receiving space, which has a geometry adapted to the geometry of the receiving space 16 and which has at least one printed circuit board and/or a punched grid and/or a busbar assembly, c) at least one or more bus conductor contacts (11, 12) for forwarding at least one power and/or data bus in the direction of arrangement to adjacent, modular connection and/or function modules, d) wherein connection and/or function blocks are separately connectable on the housing, e) wherein directly on the base terminal support or the electronics housing a connection and/or function unit is fastened, which comprises the connection and/or function blocks, f) wherein the connection and/or function unit has a holding element for the connection and/or function blocks, which is designed as a frame (21, 21'), which has at least one, two or more slots for fastening and preferably receiving the connection and/or function blocks, g) wherein the frame is connected to one of the side legs (14, 15) of the base terminal carrier via a pivot bearing, h) wherein the connection and/or function blocks have a conductive connection to the electronic circuit board, which has an electronic circuit, and i) wherein at least one of the connection and/or function blocks has signal matching electronics in addition to I/O electronics of the connection and/or function module. a) at least one base terminal carrier for fixing to a mounting base, which has a kind of U-shape, having a base leg 13, on which mounting means, preferably latching means (3, 4) for latching onto a mounting rail, are formed for mounting on the mounting rail, wherein two vertical side legs (14, 15) are integrally formed at the mutually opposite ends of the base leg to the side facing away from the mounting rail, so that a receiving space is formed between the base leg and the side legs, b) at least one electronics housing which can be attached to the base terminal carrier, which is arranged in the receiving space, which has a geometry adapted to the geometry of the receiving space 16 and which has at least one printed circuit board and/or a punched grid and/or a busbar assembly, c) at least one or more bus conductor contacts (11, 12) for forwarding at least one power and/or data bus in the direction of arrangement to adjacent, modular connection and/or function modules, d) wherein connection and/or function blocks are separately connectable on the housing, e) wherein directly on the base terminal support or the electronics housing a connection and/or function unit is fastened, which comprises the connection and/or function blocks, f) wherein the connection and/or function unit has a holding element for the connection and/or function blocks, which is designed as a frame (21, 21'), which has at least one, two or more slots for fastening and preferably receiving the connection and/or function blocks, g) wherein the frame is connected to one of the side legs (14, 15) of the base terminal carrier via a pivot bearing, h) wherein the connection and/or function blocks have a conductive connection to the electronic circuit board, which has an electronic circuit, and i) wherein at least one of the connection and/or function blocks has signal matching electronics in addition to I/O electronics of the connection and/or function module.