Type of Microprocessor :
Microprocessors fall into 3 categories:
- Single Chip Microcomputers: - Contains RWM, ROM, microprocessor, I/O port, timer and clock.
- General purpose microprocessor.
- Bit slices microprocessor.
The general purpose microprocessor have ALU with 1 or more then 1 registers which functioned as, a control unit, accumulator ,an instruction decoder which handled a fixed instruction set special and general purpose registers which varied significantly from microprocessor to microprocessor. A microprocessor can have an internal stack of fixed length or use external memory for stack. The general purpose microprocessor is available of word lengths of 16, 32, 16, 8, 4, and 1 bit.
The Bit slice microprocessor divide the functions of ALL, special purpose and general purpose registers and control unit into many ICs. For this ALU and general purpose registers were packed in separately from controls. Each register of ALU (RALU) package was really equivalent to 2 or 4-bit wide slice of registers and the ALU of the microprocessor. Bit slice processor might be cascaded to produce any unconventional or conventional word length of the microprocessor such as 4, 8, 10, 12, 16, 32 or higher bits. The control portion of bit slice processor was constructed from microprocessor sequencer IC and other logics.