1-1 Microprocessor Engineering Microprocessor Systems Microcontrollers Infineon 16-bit Processor Family  specifically 167CS microcontroller C Programming will be used throughout  Keil C166 'C' compiler  u-Vision V2 Integrated Development Environment

1-2 Microprocessor system CPU Memory – ROM and RAM Input – various Output - various

1-3 Bus system Devices connect to microprocessor via bus system (often called the memory bus) A devices connected to bus must be tri-state devices  only one device is activated at a time Consists of 3 bus types  Address bus  Data bus  Control bus

1-4 Bus operations Read Write Each read/write operation is made up of a number of clock cycles or T states Each machine instruction is made up of one or more read and/or write operations This is why we shouldn't compare microprocessors simply based on clock speed

1-5 Address Bus unidirectional – generated by microprocessor number of address lines determines number of address locations addressable locations = 2^ n where n is the number of address lines Memory map shows position of devices within the whole of the addressable area

1-6 Data Bus Bi-directional Usually matches the word length of the microprocessor Usually a multiple of 8 We talk of 8-bit, 16-bit, 32-bit and 64-bit processors which refers to the normal word length of the microprocessor

1-7 Control bus Consists of potentially many signals. Typically:-  Read  Write  Could be single signal - Read/notWrite line  Interrupt control  Bus control signals for DMA (Direct Memory Access)

1-8 Microprocessr CPU – Central Processing Unit  ALU – Arithmetic Control Unit  Registers  Control Unit ( usually microcoded)

1-9 Microprocessor Registers General purpose registers Accumulator – used in conjunction with ALU – often found on 8-bit microprocessors Status or Flag Register – inidcate result of last instruction executed Program counter Stack pointer Special registers – Instruction and memory address register

1-10 Fetch – execute cycle Fetch  memory read cycle  place in instruction register and decode Execute  may involve additional read and/or write cycles

1-11 Microcontroller A microcontroller is the integration of  microprocessor  memory ROM types – commonly flash PROM RAM – Static ram  peripherals parallel input and output Timers and Counters Serial input and output (UART, USART, etc.) Analogue to digital convertors PWM, CAPCOM registers, DACs etc.etc.