| 摘要 |
PURPOSE:To receive interruption by controlling a relocation flip flop at the end of interruption even when the relocation area is provided by extending the firmware. CONSTITUTION:The firmware is extended and the access to a relocation area is made by means of setting a relocation flip flop. If an interruption is incoming during the execution of a program in the relocation area, the present address is shunted to a stack. Since an interruption flip flop 15 is reset, the output of the relocation flip flop 14 comes to ''0'' level via an AND gate 16. In this case, all the addresses are set to ''0'' level, resulting in operating an interruption processing routine started from the address 0. Since the flip flop 15 is set after the end of interruption, the original firmware is executed. |
