Apparatus for assigning addresses to pluggable modules based on contact configuration

Claim 1

A circuit arrangement comprising a plurality of electronic circuit modules interconnected by bus means for communicating address, data and control information between the modules and a control unit, the modules being coupled to a module carrier by respective plug connection means, a plug location being associated with each plug connection means, said plug connection means comprising contact means for said address, data and control line information, and further having a plurality of contacts on which a pattern of logic signals is impressed, a different pattern being electrically associated with the respective plug location for each module as a plug location code, each module respectively having a first memory means wherein a module code indicating the type of module is stored, said first memory means being coupled to the bus means, each module respectively comprising an address comparator means coupled to the bus means for comparing addresses on said bus means, and supplied by said control unit, to the respective plug location code during an initialization phase controlled by said control unit, said control unit during said initialization phase sequentially interrogating each module on said bus means by consecutively supplying all possible plug location codes via said bus means, said module comprising means for providing said module code stored in said first memory means to said control unit, said control unit comprising means for determining the type of module from the module code from the first memory means present at each plug location, said control unit further comprising means for addressing each of the modules via said bus means and for providing to each module a respective further address for performing further data communications between the control unit and the modules, each module further comprising a second memory means coupled to the bus means having stored therein a further address for carrying on said further data communication between the control unit and said modules, said address comparator means comprising means responsive to a control signal on a control line coupling said control unit and each of said modules and for comparing the further addresses on said bus means with said further address in said second memory means after completion of the initialization phase, said plug location codes being available as further addresses after said initialization phase.