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Floating point arithmetic
the other uses a minicomputer or mainframe to assemble and simulate microprocessor programs. The author emphasizes the importance of choosing the appropriate development aid in microprocessor product development. Wantz, S P 'Is your video monitor dangerous?' Kilobaud (March 1979) pp 52-55 The author contacted every major manufacturer of TVs or computer monitors in the USA to ascertain their reactions to the renewed anxiety about the radiation danger associated with prolonged use of their products. They stated that there was little evidence that radiation posed any hazard to their consumers. After briefly reviewing the current literature on the subject the author concludes that eyestrain, not radiation, is the major problem that needs to be solved.
Software Cohen, H A and Francis, R S 'Macroassemblers and macro-based languages in microprocessor software development' Computer Vol 12 No 2 (February 1979) pp 53-64 Using a conventional macroassembler as a multitarget crossassembler and crosscompiler, the authors develop portable algorithmic code for microprocessor controllers. Their system uses a DEC- 10 mainframe and they show how the macroassembler of the
vol 3 no 6 july/aug 79
DEC can serve as a universal crossassembler.
Duntemann, J 'Onward with the COSMAC ELF!' Kilobaud (February 1979) pp 66-69 The COSMAC ELF is now reputed to be the fifth most popular microprocessor for hobbyists in the USA. The ELF has 256 bytes of RAM, a hex keyboard and two seven segment LEDs. A fundamental problem with trying to expand memory on the ELF is that the CDP 1802 IC has only eight memory address pins. To address more than 28 bytes requires the use of memory address multiplexing. The article explains the techniques needed to address up to 64k of memory. Falconer, C B 'Floating point arithmetic' Dr Dobbs Journal Vol 4 No 3 (March 1979) pp 4-14 A software package which provides full floating point arithmetic capability for 8080, 8086 and Z80 based systems, with very little decrease in speed compared with integer arithmetic. The system can handle all 16-bit integer values without any loss of information (positive integers 0 to 65 535 or signed integers in the range - 3 2 768 to +32 767). The extended range of floating point arithmetic (10 -38 to 1038) is immediately available as well as various standard mathematical functions e.g. logs, exponentials, etc.
Gagne, J 'Vice versa: PENCIL to CP/M and CP/M to PENCI L' Dr Dobbs Journal Vol 4 No 3 (March 1979) pp 26-29 CP/M users often like to use a good screen orientated editor like PENCI L. However PENCIL files are not compatible with CP/M assembler, BASIC or other programs. The software which allows PENCIL to be used with CP/M is described. Johnson, K L 'Microcomputer timesharing' Byte Vol 4 No 4 (April 1979) pp 224-234 An introductory article on the problems of using a microcomputer as the basis of a timesharing system. After reviewing some of the standard techniques i.e. scheduling methods, virtual memory and dynamic relocation of programs and data, the author gives a guide to further reading on the subject. Zimmerman, M 'Simulating physical systems: the two dimensional ideal gas' Byte Vol 4 No 4 (April 1979) pp 26-40 A simulation of a two dimensional gas made up to 256 particles on a 50 by 80 grid. The model only allows 90° coJlisions and these are said to occur when two particles fall into the same cell. The software was developed on a 6502 microcomputer - the Commodore PET. The program is a hybrid of machine language and BASIC. Machine language is used for aspects of the model which require fast processing.
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Software Cohen, H A and Francis, R S 'Macroassemblers and macro-based languages in microprocessor software development' Computer Vol 12 No 2 (February 1979) pp 53-64 Using a conventional macroassembler as a multitarget crossassembler and crosscompiler, the authors develop portable algorithmic code for microprocessor controllers. Their system uses a DEC- 10 mainframe and they show how the macroassembler of the
vol 3 no 6 july/aug 79
DEC can serve as a universal crossassembler.
Duntemann, J 'Onward with the COSMAC ELF!' Kilobaud (February 1979) pp 66-69 The COSMAC ELF is now reputed to be the fifth most popular microprocessor for hobbyists in the USA. The ELF has 256 bytes of RAM, a hex keyboard and two seven segment LEDs. A fundamental problem with trying to expand memory on the ELF is that the CDP 1802 IC has only eight memory address pins. To address more than 28 bytes requires the use of memory address multiplexing. The article explains the techniques needed to address up to 64k of memory. Falconer, C B 'Floating point arithmetic' Dr Dobbs Journal Vol 4 No 3 (March 1979) pp 4-14 A software package which provides full floating point arithmetic capability for 8080, 8086 and Z80 based systems, with very little decrease in speed compared with integer arithmetic. The system can handle all 16-bit integer values without any loss of information (positive integers 0 to 65 535 or signed integers in the range - 3 2 768 to +32 767). The extended range of floating point arithmetic (10 -38 to 1038) is immediately available as well as various standard mathematical functions e.g. logs, exponentials, etc.
Gagne, J 'Vice versa: PENCIL to CP/M and CP/M to PENCI L' Dr Dobbs Journal Vol 4 No 3 (March 1979) pp 26-29 CP/M users often like to use a good screen orientated editor like PENCI L. However PENCIL files are not compatible with CP/M assembler, BASIC or other programs. The software which allows PENCIL to be used with CP/M is described. Johnson, K L 'Microcomputer timesharing' Byte Vol 4 No 4 (April 1979) pp 224-234 An introductory article on the problems of using a microcomputer as the basis of a timesharing system. After reviewing some of the standard techniques i.e. scheduling methods, virtual memory and dynamic relocation of programs and data, the author gives a guide to further reading on the subject. Zimmerman, M 'Simulating physical systems: the two dimensional ideal gas' Byte Vol 4 No 4 (April 1979) pp 26-40 A simulation of a two dimensional gas made up to 256 particles on a 50 by 80 grid. The model only allows 90° coJlisions and these are said to occur when two particles fall into the same cell. The software was developed on a 6502 microcomputer - the Commodore PET. The program is a hybrid of machine language and BASIC. Machine language is used for aspects of the model which require fast processing.
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