An electronic detonator system includes a control unit, a plurality of electronic detonators and a bus which connects the detonators to the control unit. Each electronic detonator includes a number of flags which may assume either of two possible values, each flag indicating a substrate of the respective detonators. The flags are readable from the control unit by means of digital data packets and the control unit is adapted, by means of these flags, to check the state of the electronic detonator and control the operation of the electronic detonator. When reading the flags, the electronic detonators give responses in the form of analog response pulses on the bus. The detonator system also includes a portable message receiver which on the basis of the flags obtains messages regarding the connecting status of a detonator.