| 摘要 |
PURPOSE:To improve the ability of microprogram control in scanning processing without adding any hardware by nesting comparing data in a RAM so that the final data of a record is in the tail address of the RAM. CONSTITUTION:The head address of the 1st record from a microprocessor muP1 is loaded in an address register 4 and the address obtained by subtracting one record length from the tail address of the RAM3 is loaded in an address register 2. Further, a chip select signal CS is sent out to RAMs 3 and 5, which are accessed on the basis of the contents of the registers 2 and 4 to read respective data. Those data are inputted to the muP1, which compares and collates those data to sent a 1-count-up indication UP to the registers 2 and 4 when the input data coincide with each other. Thus, when the register 2 counts up to the address of the final data of one record, an overflow signal 7 is inputted to the muP1, which knows the completion of the comparison and collation of the 1st record and checks whether the condition are satisfied or not. |
