Microassembler

A microassembler is a computer program that helps prepare a microprogram, called firmware, to control the low level operation of a computer in much the same way an assembler helps prepare higher level code for a processor. The difference is that the microprogram is usually only developed by the processor manufacturer and works intimately with the computer hardware. On a microprogrammed computer the microprogram implements the operations of the instruction set in which any normal program (including both application programs and operating systems) is written. The use of a microprogram allows the manufacturer to fix certain mistakes, including working around hardware design errors, without modifying the hardware. Another means of employing microassembler-generated microprograms is in allowing the same hardware to run different instruction sets. After it is assembled, the microprogram is then loaded to a control store to become part of the logic of a CPU's control unit.