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Semiconductor Group
11
Fundamental Structure
Central Processing Unit
The CPU is designed to operate on bits and bytes. The instructions, which consist of up to 3 bytes,
are performed in one, two or four machine cycles. One machine cycle requires twelve oscillator
cycles. The instruction set has extensive facilities for data transfer, logic and arithmetic instructions.
The Boolean processor has its own full-featured and bit-based instructions within the instruction set.
The SAB 80(C)515/80(C)535 uses five addressing modes: direct access, immediate, register,
register indirect access, and for accessing the external data or program memory portions a base
register plus index-register indirect addressing.
Memory Organization
The SAB 80C515, 80515 have an internal ROM of 8 Kbyte. The program memory can externally be
expanded up to 64 Kbyte (see bus expansion control). The internal RAM consists of 256 bytes.
Within this address space there are 128 bit-addressable locations and four register banks, each
with 8 general purpose registers. In addition to the internal RAM there is a further 128-byte address
space for the special function registers, which are described in sections to follow.
Because of its Harvard architecture, the SAB 80(C)515/80(C)535 distinguishes between an
external program memory portion (as mentioned above) and up to 64 Kbyte external data memory
accessed by a set of special instructions.
Bus Expansion Control
The external bus interface of the SAB 80(C)515/80(C)535 consists of an 8-bit data bus (port 0), a
16-bit address bus (port 0 and port 2) and five control lines. The address latch enable signal (ALE)
is used to demultiplex address and data of port 0. The program memory is accessed by the program
store enable signal (PSEN) twice a machine cycle. A separate external access line (EA) is used to
inform the controller while executing out of the lower 8 Kbyte of the program memory, whether to
operate out of the internal or external program memory. The read or write strobe (RD, WR) is used
for accessing the external data memory.
Peripheral Control
All on-chip peripheral components - I/O ports, serial interface, timers, compare/capture registers,
the interrupt controller and the A/D converter - are handled and controlled by the so-called special
function registers. These registers constitute the easy-to-handle interface with the peripherals. This
peripheral control concept, as implemented in the SAB 8051, provides the high flexibility for further
expansion as done in the SAB 80(C)515/80(C)535.
Moreover some of the special function registers, like accumulator, B-register, program status word
(PSW), stack pointer (SP) and the data pointer (DPTR) are used by the CPU and maintain the
machine status.
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Содержание SAB 80515 Series
Страница 9: ...Semiconductor Group 9 Introduction Figure 1 2 Block Diagram ...
Страница 12: ...Semiconductor Group 12 Fundamental Structure Figure 2 1 Detailed Block Diagram ...
Страница 18: ...Semiconductor Group 18 Central Processing Unit Figure 3 1 Fetch Execute Sequence ...
Страница 22: ...Semiconductor Group 22 Memory Organization Figure 4 3 Mapping of the Lower Portion of the Internal Data Memory ...
Страница 30: ...Semiconductor Group 30 External Bus Interface Figure 5 1 a and b External Program Memory Execution ...
Страница 38: ...Semiconductor Group 38 On Chip Peripheral Components Figure 7 3 Output Driver Circuits of Ports 1 through 5 ...
Страница 59: ...Semiconductor Group 59 On Chip Peripheral Components Figure 7 16 a Functional Diagram Serial Interface Mode 0 ...
Страница 60: ...Semiconductor Group 60 On Chip Peripheral Components Figure 7 16 b Timing Diagram Serial Interface Mode 0 ...
Страница 61: ...Semiconductor Group 61 On Chip Peripheral Components Figure 7 17 a Functional Diagram Serial Interface Mode 1 ...
Страница 62: ...Semiconductor Group 62 On Chip Peripheral Components Figure 7 17 b Timing Diagram Serial Interface Mode 1 ...
Страница 73: ...Semiconductor Group 73 On Chip Peripheral Components Figure 7 25 A D Converter Block Diagram ...
Страница 83: ...Semiconductor Group 83 On Chip Peripheral Components Figure 7 33 a Timer 2 Block Diagram ...
Страница 111: ...Semiconductor Group 111 On Chip Peripheral Components Figure 7 54 Timing Diagram System Clock Output ...
Страница 113: ...Semiconductor Group 113 Interrupt System Figure 8 1 a Interrupt Structure of the SAB 80 C 515 80 C 535 ...
Страница 114: ...Semiconductor Group 114 Interrupt System Figure 8 1 b Interrupt Structure of the SAB 80 C 515 80 C 535 cont d ...
Страница 204: ...Semiconductor Group 204 Instruction Set XCH A Ri Operation XCH A Ri Bytes 1 Cycles 1 Encoding 1 1 0 0 0 1 1 i ...
Страница 215: ...Device Specifications Semiconductor Group 215 ...
Страница 217: ...Device Specifications Semiconductor Group 217 Pin Configuration P LCC 68 ...
Страница 219: ...Device Specifications Semiconductor Group 219 Logic Symbol ...
Страница 226: ...Device Specifications Semiconductor Group 226 Figure 1 Block Diagram ...
Страница 229: ...Device Specifications Semiconductor Group 229 Figure 2 Memory Address Spaces ...
Страница 239: ...Device Specifications Semiconductor Group 239 Figure 4 Block Diagram of the A D Converter ...
Страница 241: ...Device Specifications Semiconductor Group 241 Figure 5 Interrupt Request Sources ...
Страница 242: ...Device Specifications Semiconductor Group 242 Figure 6 Interrupt Priority Level Structure ...
Страница 268: ...Device Specifications Semiconductor Group 268 AC Testing Input Output Waveforms AC Testing Float Waveforms ...