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Asynchronous-sampling method simplifies dual-port memories
Hardware Alexy, G and Katz, B J 'Multiprocessing increases power of inexpensive pP-based designs' EDN Vol 25 No 10 (20 May 1980) pp 161166 Advantages of multiprocessing techniques are discussed. A practical example is given of a triple-processor system. Each CPU supports a resident bus for individual RAM, ROM and peripherals.
Brodsky, M 'Hardening RAMs against soft errors' Electronics Vol 53 No 10 (24 April 1980) pp 117-122 The article discusses soft-error mechanisms in dynamic RAMs and describes instrumentation and test procedures for measuring device susceptibility to alpha radiation. Recommendations are made for design features which will minimize alpha-induced soft errors. Increasing supply voltage and cycle time are examples of external factors, while circuit changes such as increasing charge capacity of the memory cell are also beneficial.
Buurma, J 'Most "pP-compatible" ADCs still require extra support' EDN Vol 25 No 9 (5 May 1980) pp 161-164 Requirements for interfacing A/D converters with microprocessors are considered. There is some guidance given in evaluating nonstandard datasheet terms and specifications. Matching up power supply requirements is also shown to be of importance, as is compatibility with the processor's control lines.
Kinzer, D 'A time-sharing/multiuser subsystem for ~nicroprocessors' Byte Vol 5 No 6 (June 1980) pp 122-134 The article gives details of a 16-user timesharing system and principles used
vol 4 no 8 october 80
in its implementation. Practical details and diagrams are provided of hardware interrupt techniques used, plus listings of software rou tines.
Lavi, Y et al '16-bit microprocessor enters virtual memory domain' Electronics Vol 53 No 10 (24 April 1980) pp 123-129 A 16-bit microprocessor is described which supports virtual memory systems and can address 16 Mbyte. A memory management unit offers an instruction aborting facility and the central processor supports 24-bit addresses.
McCracken, D 'Hybrid tool for universal microprocessor development' Computer Des. Vol 19 No 4 (April 1980) pp 119-126 A single-board universal interface is described for use between a microprocessor under development and an interactive personal computer. All the features of an emulator are provided for the cost of a single-board dedicated system. The interface serves as both writable program store for the microprocessor and bidirectional communications channel. Alternatively a CPU personality card may be plugged in to provide development for new applications.
Schmidt, R W 'Asynchronous-sampling method simplifies dual-port memories' EDN Vol 25 No 8 (20 April 1980) pp 201204 A technique is described for handling memory-interface applications such as processor-processor and processordisc controller corrections which require dual-port memories. Asynchronous sampling involves connection of the devices to shared RAM array via input multiplexers and input and output latches. Governed by a clock, these allocate memory access to the two ports alternatively for data, address and control transactions.
Software Bilton, J M 'A survey of self-test and BITE program generation' Euromicro Vol 6 No 3 (May 1980) pp 168-174 BITE (built-in test equipment) and self-test methods of testing microprocessor-based equipment are discussed. Problems of implementation and assessingtest effectiveness are considered, and there are suggestions for selecting appropriate tests for particular equipment.
Hansen, G 'User-generated microprograms improve mini performance' EDN Vol 25 No 9 (5 May 1980) pp 145-150 Microprogramming for end users of microprocessor-based systems is discussed. The article explains how to assessa program's suitability for use with microprogramming techniques by analysing time spent on various tasks and determining if the time can be reduced by improved algorithm design. Advice on writing and verifying the microprogram is given, with examples.
Jones, J 'Towards a HLL oriented microprocessor instruction set' Euromicro Vol 6No 3 (May 1980) pp 158-160 The instruction set of a microprocessor designed to execute block-structured, procedure-oriented languages such as PASCAL is described. The set is twodimensional and is implemented on a machine of bit-slice construction. The design is such that coding in assembly language is unnecessary; PASCAL is the machine's assembly language.
Korody, R and Raaum, D 'Purge your memory array of pesky error bits' EDN Vol 25 No 10 (20 May 1980) pp 153-158 The article explains how to remove single-bit errors from micro-
315
Brodsky, M 'Hardening RAMs against soft errors' Electronics Vol 53 No 10 (24 April 1980) pp 117-122 The article discusses soft-error mechanisms in dynamic RAMs and describes instrumentation and test procedures for measuring device susceptibility to alpha radiation. Recommendations are made for design features which will minimize alpha-induced soft errors. Increasing supply voltage and cycle time are examples of external factors, while circuit changes such as increasing charge capacity of the memory cell are also beneficial.
Buurma, J 'Most "pP-compatible" ADCs still require extra support' EDN Vol 25 No 9 (5 May 1980) pp 161-164 Requirements for interfacing A/D converters with microprocessors are considered. There is some guidance given in evaluating nonstandard datasheet terms and specifications. Matching up power supply requirements is also shown to be of importance, as is compatibility with the processor's control lines.
Kinzer, D 'A time-sharing/multiuser subsystem for ~nicroprocessors' Byte Vol 5 No 6 (June 1980) pp 122-134 The article gives details of a 16-user timesharing system and principles used
vol 4 no 8 october 80
in its implementation. Practical details and diagrams are provided of hardware interrupt techniques used, plus listings of software rou tines.
Lavi, Y et al '16-bit microprocessor enters virtual memory domain' Electronics Vol 53 No 10 (24 April 1980) pp 123-129 A 16-bit microprocessor is described which supports virtual memory systems and can address 16 Mbyte. A memory management unit offers an instruction aborting facility and the central processor supports 24-bit addresses.
McCracken, D 'Hybrid tool for universal microprocessor development' Computer Des. Vol 19 No 4 (April 1980) pp 119-126 A single-board universal interface is described for use between a microprocessor under development and an interactive personal computer. All the features of an emulator are provided for the cost of a single-board dedicated system. The interface serves as both writable program store for the microprocessor and bidirectional communications channel. Alternatively a CPU personality card may be plugged in to provide development for new applications.
Schmidt, R W 'Asynchronous-sampling method simplifies dual-port memories' EDN Vol 25 No 8 (20 April 1980) pp 201204 A technique is described for handling memory-interface applications such as processor-processor and processordisc controller corrections which require dual-port memories. Asynchronous sampling involves connection of the devices to shared RAM array via input multiplexers and input and output latches. Governed by a clock, these allocate memory access to the two ports alternatively for data, address and control transactions.
Software Bilton, J M 'A survey of self-test and BITE program generation' Euromicro Vol 6 No 3 (May 1980) pp 168-174 BITE (built-in test equipment) and self-test methods of testing microprocessor-based equipment are discussed. Problems of implementation and assessingtest effectiveness are considered, and there are suggestions for selecting appropriate tests for particular equipment.
Hansen, G 'User-generated microprograms improve mini performance' EDN Vol 25 No 9 (5 May 1980) pp 145-150 Microprogramming for end users of microprocessor-based systems is discussed. The article explains how to assessa program's suitability for use with microprogramming techniques by analysing time spent on various tasks and determining if the time can be reduced by improved algorithm design. Advice on writing and verifying the microprogram is given, with examples.
Jones, J 'Towards a HLL oriented microprocessor instruction set' Euromicro Vol 6No 3 (May 1980) pp 158-160 The instruction set of a microprocessor designed to execute block-structured, procedure-oriented languages such as PASCAL is described. The set is twodimensional and is implemented on a machine of bit-slice construction. The design is such that coding in assembly language is unnecessary; PASCAL is the machine's assembly language.
Korody, R and Raaum, D 'Purge your memory array of pesky error bits' EDN Vol 25 No 10 (20 May 1980) pp 153-158 The article explains how to remove single-bit errors from micro-
315