| 摘要 |
PURPOSE:To use a jump instruction to change a program without holding the number of words to be changed, by providing a microprogram change controlling circuit, a selecting circuit, etc. in a controller. CONSTITUTION:An instruction address is held in an address register 1 of a microprogram controller, and an ROM10 and a comparing circuit 30 are connected to the register 1 through an address information line 100, and a storage circuit 20 where an address is stored is connected to the circuit 30, and addresses are compared by the circuit 30 in case of the patch mode. A program to be changed is stored in a storage circuit 21, and patch words are set in accordance with the operation of a shift register 40. Meanwhile, the address of the circuit 30 is applied to a microprogram changing circuit 50, and the output of the circuit 50 is applied to the register 40 through an FF60. Contents of the ROM10 and the storage circuit 21 are selected by a selecting circuit 41, and a jump instruction is used to facilitate changing of the program. |
