Appendix A: Microprocessor Data Sheets Intel8085 Zilog Z80 MOS Technology 6502 Motorola 6809 Microcontrollers (Single-chip Microcomputers) Intel 8086 ( & 80186 & 80286) Zilog Z8000 Motorola 68000 32-bit Microprocessors lnmos Transputer 184 Appendix A 185 Intel 8085 Followed on from the 8080, which was a two-chip equivalent of the 8085. Not used in any home computers, but was extremely popular in early (late 1970s) industrial control systems. A15-A8 A B c D E Same register AD7-ADO H L set is used in SP 8080 PC ALE Flags Multiplexed d ata bus and lower half of address bus (require 8212 to split data and address buses) Start addresses of Interrupt P/Os Service Routines: 8155- 3 ports, 256 bytes RAM RESET-()()()(J 8255 - 3 ports TRAP- 0024 8355 - 2 ports, 2K ROM RST5.5- 002C 8755 - 2 ports, 2K EPROM RST6.5 - ()(J34 RST7.5- <XJ3C INTR - from interrupting device Other 8251- USART 8202 - Dynamic RAM controller support 8253- CTC (3 counters) 8257 - DMA controller devices: 8271 - FDC 8257 - CRT controller Intel DMA Control System Character CPU buses­ de-multiplexed Video signal to CRT 186 Microcomputer Fault-finding and Design Zilog Z80 Probably the most popular 8-bit microprocessor. Used in home computers (Spectrum, Amstrad, Tandy), office computers and industrial controllers. A F A' F' B c B' C' D E D' E' H L H' L' 8 data Interrupt Memory lines vector I refresh R Index register IX Index register IY (to refresh dynamic RAMI Stack pointer Based on the Intel 8085, but possesses second set of registers. /SR (Interrupt Service Routine) start addresses RESET-0000 NMI- 0066 INT- CPU obeys contents of Interrupt Vector for CPU 'mode 0' - 0038 for CPU 'mode 1' - XXYY for CPU 'mode 2' (XX is contents of Interrupt Vector YY is supplied on Data Bus from interrupting device) 'Vector' (CPU examines XXYY to find start address of ISR) ZBO P/0 ZBO CTC External pulses CLK/TRO "'CLK/TRT Address CLK/TR2 Port A CLK/TRJ Data ZBO PIO ZC/TOO ZC/TOT ZC/T02 I Zero count, or Timeout 4 addresses: 00- Port A (data) 4 channels (counters). Each 01- Port A (control) possesses its own control 10- Port B (data) register - same address as 11 -Port B (control) counter. Send OF to Control register for output port, 4F for input port. Appendix A 187 Zilog ZSO ZBO DART TxARxA } Address TxCA Channel A Duai-UART (Z80 SIO RxCA is almost Data Modem control identical, zso ----- signals (DTR, DART but offers DSR, RTS, CTS) additional also synchronous TxB } transmission) RxB Channel B TxCB - RxCB ZBO 'Daisy-chain' Interrupt System Common (shared) mterrupt line - lEI; ~ !NT Interrupt enable in f lEO; Interrupt I I enable out !NT !NT !NT CPU PIO CTC DART lEI lEO lEI lEO lEI lEO 1 (+5 vd 1 1 1 I I 0 l I ooL Daisy-chain ~ Daisy-chain broken (CTC is interrupt active). so DART cannot generate an interrupt 188 Microcomputer Fault-finding and Design MOS Technology 6502 Very popular 8-bit microprocessor used in home computers, such as BBC, Apple 2, Acorn Atom, Commodore PET and VIC 20. Other members of the family possess only 28 pins, such as 16 6503 - 12 address lines address 6504- 13 address lines lines Accumulator A Index register X 8 data Index register Y lines I PCH I PCL Program counter PC Stack pointer SP Status register Memory Map 0000 Zero page Page 0 - Can be used as registers (256 bytes) within instructions OOFF (memory, so slow transfers) 0100 Stack Page 1 (256 bytes) (must 01FF beRAMI P/0 0200 User area FFFA } NMI FFFB vector FFFC } RESET FFFD vector FFFE LSB IRQ } FFFF MSB vector Possesses 2 ports, 2 counters UART No input/output instructions (like 6809), TxD}RxD Data so memory mapped input/output must be used. Data P/0/Memory 6530- 2 ports, 1 counter, IK ROM, 64 bytes RAM 50 baud to 19200 baud Appendix A 189 Motorola 6809 Developed by Motorola when A B Accumulators the 6502's popularity I DP Flags exceeded that of Motorola's I 6800. Probably the most X Index } powerful 8-bit y registers microprocessor (possesses SP (User) multiply and divide instructions and some SP (System) 16-bit operations). PC A and B can be combined as a 16-bit register D. MC6809 Predecessor 6800 does not CPU possess DP (Direct Page), Y or second SP. 8 data lines Memory Map P/0 0000 .....------, Base page OOFF 0100 1------1 FFFB }IRQ FFF9 vector 2 ports only (no counters) FFFA } SWI- software interrupt vector FFFB FFFC UART } NMI vector FFFD FFFE LSB TxD} } RESET RxD Data vector FFFF MSB Address the similarity of these Data 6850 Notice A CIA devices to the MOS Technology (UART) support devices (6522 PIO RTS and 6551 UART). These devices CTS can be used with the 6809. DCD Tx and Also Rx clocks 1 6839 - mathematics firmware Handshaking 6829 - memory management unit 190 Microcomputer Fault-finding and Design Motorola 6809 Application- VDU Design Address bus J J 128 8K RAM 6809 1K Address bytes (display CPU ROM Data r r RAM r buffer) Data bus ...._ Video Character Shift Address generator f- register f--. to - ROM CRT J j_ CRT J UART Keyboard 6850 encoder controller 6845 I r r ASCII characters received from remote computer (through UART) are loaded into 8K RAM (display buffer). CRT controller removes these bytes and uses Character generator ROM to generate row for the dot matrix for each character. Appendix A 191 Microcontrollers (Single-chip Microcomputers) These devices employ 8-bit CPUs, but include some memory and input/ output. This single-chip solution often produces a smaller and cheaper assembly for such applications as: (a) washing machine controller; (b) telephone answering machine. The instruction set is not normally easy to use, and instructions are 1 or 2 bytes long. Typical pin functions: Port 1 Sometimes the address Port 2 and data bus lines are multiplexed with the port lines to Port 3 allow external devices to be connected. Intel Microcontrollers The most commonly used members of the Intel family are: (1) 8048- 3 ports, 1 counter, 64 bytes RAM, 1K ROM (2) 8748- 3 ports, 1 counter, 64 bytes RAM, 1K EPROM (3) 8035- 3 ports, 1 counter, 64 bytes RAM (no ROM) (4) 8049- 3 ports, 1 counter, 128 bytes RAM, 2K ROM (5) 8022- 3 ports, 1 counter, 64 bytes RAM, 1K ROM, 1 ADC (6) 8051- 3 ports, 1 counter, 128 bytes RAM, 4K ROM, 1 UART plus extra instructions (for example, multiply and divide) Zilog Microcontrollers (1) Z8601- 4 ports, 2 counters, 1 UART, 144 bytes RAM, 2K ROM (2) Z8602- 4 ports, 2 counters, 1 UART, memory buses (3) Z8603- 4 ports, 2 counters, 1 UART, 144 bytes RAM, 2K ROM, 2K EPROM ('piggy-backed' on top of device) (4) Z8681- 4 ports, 2 counters, 1 UART, memory buses (5) Z8611, Z8612 and Z8613- 4K versions of (1), (2) and (3) (6) Z8671- as (1) with BASIC interpreter 192 Microcomputer Fault-finding and Design Intel 8086 (& 80186 & 80286) This is the most popular 16-bit microprocessor family and is based on the 8086/8088 devices. One of the derivatives (8088, 80186 or 80286) is used in nearly all DOS-based 16-bit office computers (IBM PC, Amstrad, Apricot, Sirius). Intel were the first manufacturer to produce 16-bit devices and took control of the market. A19-A16 1 Mbyte address 1---..:::4~/ ~i~:ess range 8088 has only CLK= 8066 8-bit data bus 5-10 MHZ CPU lA07-ADOI Control lines 40·pin OIL 15 0 AH AL BH BL registers CH CL All registers are 16-bit DH DL }- Opcode is SP byte length BP Sl registers 01 }'- CPU Architecture (of 8086 & 8088) Execution Unit lEU I Bus Interface Unit lBIUI Segment registen 141 Multiplexed bus system --4 bytes for 8088 6 bytes for 8088 ("pipeline") Appendix A 193 Intel 8086 (& 80186 & 80286) Instructions arc pre-fetched from memory and placed in Instruction Queue (or ·pipeline') to increase program execution speeds. The segment registers allow program (code). data and stack to occupy different MK memory segments. Memon· Segmentation Memory Example 1 Code Code segment (CS) (64K) JsoooJ Segment registers Add _f J4000J PC Code segment ICS) Data Result J64000J Physical address Data segment IDS) (64K) to memory Stack segment ISS) Example 2 Extra segment (ES) J3000J Data segment I OS) Stack Add L (64K) J6789J Offset I 16-bit) As each address leaves the CPU, it is modified by Rosult J36789J Physical address the contents of one to memory of the segment registers Application of8086 (Apricot Computer) ALE A19-A16 To/from 16K EPROM 512K RAM A 15-AO ldynamicl UART FDC etc. 015-DO I. The XOX7 performs floating point arithmetic ( + high precision fixed point arithmetic. mathematical functions. such as SINE). 2. The XOXY handles 1/0 transfers (such as DMA transfers to/from floppy or hard disk). 194 Microcomputer Fault-finding and Design Intel 8086 (& 80186 & 80286) 80186 As 8086, plus the following on-chip functions: 1. Clock generator 2. Chip select logic (7 1/0, 6 memory) 3. Timers (3) 4. DMA control (2 channels) 5. Programmable interrupt controller. Mounted in a 64-pin JEDEC 'chip carrier'. 80286 Similar to the 8086, but it provides memory management and virtual memory facilities. Segment registers have a different role in order to perform 'memory management': Program change occurs, and segment registers point to memory locations, from which 48-bit segment descriptor registers are transferred to a 'cache' on the CPU.