| 摘要 |
PURPOSE:To change a program started by the same absolute address, in an unmanned state, by providing plural pieces of ROMs, and resetting a CPU by selecting the ROM corresponding to set information from the outside. CONSTITUTION:In ROMs 3-5, each different program is stored from an absolute address 0000H. Also, address lines A0-A15 are connected to other memory system, as well. A control circuit 2 is a circuit for selecting the ROMs 3-5, and constituted of an EEPROM 10 and a one-chip microcomputer 11. In this state, OR of set information from an external apparatus or a front panel operating part, and the address line A15 is taken, and a chip selecting signal for selecting the ROMs 3-5 is generated. Accordingly, in case of changing a control program, when the set information is inputted to the control circuit 2, a desired ROM can be selected automatically by the control circuit 2.
|
