| 摘要 |
PURPOSE:To shorten the interval of data accessing to a memory by generating two-dimensional addresses with use of two independent address counters. CONSTITUTION:When a memory access start instruction is outputted, an initial value is set up in a row address initial value register 5 and a column address initial value register 6 and a memory access word length is set up in a word length counter 8. Then, an address counter is enabled to count and driven in accordance with 4-row direction access or column direction access under the control by a mode register so as to increase or decrease its contents in accordance with count-up or count-down mode. The word length counter 8 also counts up its contents every generation of one address. When the counter 8 ends the counting corresponding to the generated addresses and a carry is inputted to a mode register 7, the generation of addresses is stopped.
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