MC68B00

MCWOO I i 8-BIT MICROPROCESSING UNIT (MPU) I The MC6800 is a monolithic 8-bit microprocessor forming the central control function for Motorola’s M68~ family. Compatible with TTL, the MC6B~, as with all M6800 system parts, requires only one + 5.O-volt power supply, and no external TTL devices for bus interface. The MC6800 is capable of addressing 64K bytes of memory with its 16-bit address lines. The 8-bit data bus is bidirectional as well as threestate, making direct memory addressing and multiprocessing applications realizable. q 8-Bit Parallel Processing q Bidirectional Data Bus – Variable Length Indexed, . . 16-Bit Address Bus – WK Bytes of Addressing Seven Addressing Modes – Direct, Relative, Immediate, Extended, Implied and Accumulator q 72 Instructions ,>: ,,*!. “)!.IC,[ . Vectored Restart .}. ‘.*$ ,,2:+.( ~ ‘~”‘%1 *F. . Maskable Interrupt Vector ~ ..!’. . Separate Non-Maskable Interrupt – Internal Registers Saved i#’’::$$ , +, ~, ,)i ~ . ,{). .Y,:>, -,,,. .,,,!,. Stack .... ... *: ,.. ‘is . Six Internal Registers – Two Accumulators, Index Regist~#?Y’:Y’ Program Counter, Stack Pointer and Condition Code Re~@te~ q Direct Memory Addressing (D MA) and Multiple P~@$esso’r > .:;.!,.,, .s,-. .+ Capability ,“ ,., ., ,1’.‘ --> ,,: ~.., *V \>>>., ,+ **. q Simplified Clocking Characteristics ‘~:?iii * ...*”,+< ,,:+,.., ‘.~;:),t.{t,. . Clock Rates as High as 2.0 MHz ,~> *:;.> q Simple Bus Interface Without TTL ,$~~~~i$~’ q Variable Length Stack q Halt and Single Instruction ...