| 摘要 |
A microcomputer terminal system having a list mode of operation for the video refresh circuit. Stored in the main memory are list address pointers. Video circuits read a list address pointer at a designated location in the main memory. The list address pointer points the video circuits to the beginning of a list. The main memory stores the list. The list comprises control data, character count and a data address pointer. The data address pointer of the addressed list is read by the video circuits. By reading the data address pointer of the addressed list, the video circuits are pointed to the storage location of the main memory for the character data to be displayed on the video screen. On each refresh cycle of the video screen, the video circuits progress element-by-element through the list generating the display. The video circuits return to the beginning of the addressed list for the next refresh cycle.
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