Test signal generating apparatus

A device test system comprising:

• a test signal generating apparatus for generating a test signal to be transmitted to a device under test, said device under test outputting a signal in response to said test signal;
• and a signal verifying apparatus for verifying said signal received from said device under test,
• said test signal generating apparatus comprising:
• a test signal generating unit for generating the test signal;
• a pattern storage unit having patterns to be selected for said test signal;
• a pattern map storage unit having a pattern map defining the number of repetitions for each pattern and a pattern corresponding to a test signal to be generated by said test signal generating unit after said test signal generating unit repeats said test signal on the basis of said number of repetitions;
• and a pattern selecting unit for selecting, from among said patterns stored in the pattern storage unit, a pattern corresponding to the test signal to be generated by said test signal generating unit,
• said signal verifying apparatus comprising a reference pattern storage unit having reference patterns corresponding to said patterns to be selected for said test signal, wherein
• said test signal generating apparatus further comprises a trigger signal receiving unit for receiving at least one trigger signal, and a pattern information transmitting unit for transmitting pattern information indicative of said pattern selected by said pattern selecting unit,
• said signal verifying apparatus further comprises a signal verifying unit for verifying, on the basis of a reference pattern corresponding to a pattern represented by said pattern information transmitted from said pattern information transmitting unit, said signal received from said device under test,
• said pattern map defines a pattern corresponding to said trigger signal,
• when said trigger signal is received by said trigger signal receiving unit under the condition that said test signal generating unit is repeatedly generating a test signal having a pattern selected by said pattern selecting unit on the basis of said number of repetitions defined by said pattern map, said pattern selecting unit selects a pattern corresponding to said trigger signal received by said trigger signal receiving unit on the basis of said pattern map.