Data expansion apparatus

Data expansion apparatus for processing data to be transmitted to a using device, comprising:

• storage means having an output and containing addressable storage locations storing a mixture of data and compact representations of data;
• said compact representations of data each including a coded flag signifiying that it is a compact representation;
• an address field identifying the initial location address in said stoarge means of a predetermined data sequence;
• a length field indicating the length of said sequence;
• and
• a count field indicating a predetermined number of repetitions of said sequence to be sequentially transmitted to said using device;
• gating means connecting the output of said storage means to said using device for transmission of data from said storage means to said using device;
• deconding means connected to the output of said storage means;
• said decoding means being responsive to the occurrence of a flag at the output of said storage means to inhibit said gating means, thereby interrupting transmission of data from said storage means to said using device, said flag having been read from a storage location having an address n;
• first register means;
• means responsive to the occurrence at the output of said storage means fo said address field, said length field and said count field to cause said first register means to store indications of the initial location, the length and the number of repetitions, respectively, of said sequence;
• means to cause transmission of said sequence from said storage means to said using device;
• and
• control means responsive to the completion of transmission of said sequence the number of repetitions indicated in said first register means to cause recommencement of storage access from the storage location which has and address of n + i, where i equals the length of a compact representation of data.