Processes for testing bi-directional serial transmissions, and circuits for their implementation

A method for testing a first transceiver connected by a transmission link to a second similar transceiver, said link being constituted by at least one transmission line (L, L*), said transceivers including, for each line (L, L*), an adaptation impedance (R) connected to said transceivers and amplification means (1) to produce transmission signals over said line (L, L*) in response to transmission command signals (e, e*) and to produce reception signals (s, s*) in response to transmission signals produced over said line (L, L*) by the second similar transceiver, the method comprising the steps of disconnecting the adaptation impedance (R) from each line (L, L*) in each said transceiver, producing transmission command signals (e, e*) and comparing them to the reception signals furnished by said amplification means (1).

A method for testing a first transceiver connected by a transmission link to a second similar transceiver, said link being constituted by at least one transmission line (L, L*), said transceivers including, for each line (L, L*), an adaptation impedance (R) connected to said transceivers and amplification means (1) to produce transmission signals over said line (L, L*) in response to transmission command signals (e, e*) and to produce reception signals (s, s*) in response to transmission signals produced over said line (L, L*) by the second similar transceiver, the method comprising the steps of disconnecting the adaptation impedance (R) from each line (L, L*) in said second transceiver, producing transmission command signals (e, e*) and comparing them to the reception signals (s, s*) furnished by said amplification means (1).

A method for testing a parallel-serial and serial-parallel interface, including serialization-deserialization means (14) having parallel inputs and outputs (DT) and serial inputs and outputs connected to at least one transceiver (12), each transceiver adapted to be connected by a transmission link to another similar transceiver, said link being constituted by at least one transmission line (L, L*), said transceivers including, for each line (L, L*), an input-output terminal (B) connected to said line (L, L*), an adaptation impedance (R) connected between said terminal (B) and a fixed voltage (V.sub.dd) and amplification means (1) to produce transmission signals over said terminal (B) in response to transmission command signals (e, e*) furnished from said serialization-deserialization means and to produce reception signals (s, s*) intended for said serialization-deserialization means in response to transmission signals produced over said terminal (B) by the second similar transceiver, said method comprising the steps of:

• disconnecting said transmission link from terminal (B) of at least one transceiver;
• and applying to said parallel inputs data transmission signals involving one of said non-connected transceivers, and comparing said data transmission signals to the signals present at said parallel outputs (DT).

A method for testing a parallel-serial and serial-parallel interface, including serialization-deserialization means (14) having parallel inputs and outputs (DT) and serial inputs and outputs connected to at least one transceiver, at least one transceiver being connected by a transmission link to another similar transceiver, said link being constituted by at least one transmission line (L, L*), said transceivers including, for each line (L, L*), an adaptation impedance (R) connected to said transceiver and amplification means (1) to produce transmission signals over said line (L, L*) in response to transmission command signals (e, e*) furnished from said serialization-deserialization means and to produce reception signals (s, s*) intended for said serialization-deserialization means in response to the transmission signals produced over said line (L, L*) by the other similar transceiver, the method comprising the steps of disconnecting the adaptation impedance from each line connected to at least one of said transceivers, applying to said parallel inputs, data transmission signals involving one of said connected transceivers, the adaptation impedances of which are disconnected, and comparing said data transmission signals to the signals present at said parallel outputs.

A method for testing a parallel-serial and serial-parallel interface, including serialization-deserialization means (14) having parallel inputs and outputs (DT) and serial inputs and outputs connected to at least one transceiver, at least one transceiver being connected by a transmission link to another transceiver of the same constitution, said link being constituted by at least one transmission line (L, L*), said transceivers including, for each line (L, L*), an adaptation impedance (R) connected to said transceivers and amplification means (1) to produce transmission signals over said line (L, L*) in response to transmission command signals (e, e*) furnished from said serialization-deserialization means and to produce reception signals (s, s*) intended for said serialization-deserialization means in response to the transmission signals produced over said line (L, L*) by the said another transceiver, the method comprising the steps of disconnecting the adaptation impedance from each line connected to said another transceiver, applying to said parallel inputs, data transmission signals intended for said another transceiver, the adaptation impedances of which are disconnected, and comparing said data transmission signals to the signals present at said parallel outputs (DT).