Z80 ALGOL-60

nels, each of which is separately configured. Programmable control registers provide control for the transfer location and length, individual channel control and transfer-mode configuration, priority of servicing, data chaining, and interrupt control. Status and control lines provide control to the peripheral controllers. The mode of transfer for each channel can be programmed as cycle-stealing or a burst-transfer mode. A CRT controller, MC 6845, interfaces M6800 systems to raster-scan displays. Video timing and refresh memory addressing are performed by the chip. Other functions such as cursor movements, keyboard control and editing are left to the host CPU. (Motorola Limited, Semiconductor Products Division, York House, Empire Way, Wemb/ey, Middlesex HA 90PR, UK. Tel: 01-902 8836. Telex: 21740 MOTSEM Wemb/ey)

Powerful capabilities featured in the new 5BC 80/30 include 16 kbytes of dual port RA M, sockets for an 8041/8 741 universal peripheral interface, full Multibus bus control logic allowing up to 16 masters to share the system bus, a 12level vectored priority-interrupt structure, a programmable communications interface, 24 programmable I / 0 lines with sockets for interchangeable line drivers and line terminators and system/development software support. Dual-port capability allows the onboard RAM to be accessed by both the onboard CPU and any other external Multibus master interfaced to the system. By permitting direct access to the RAM from the system bus, other Multibus masters (e.g. DMA devices, other SBCs) can exchange data via common memory, eliminating the need for additional memory expansion boards.

Z80 ALGOL-60 An ALGOL-60 compiler, previously running on PDP 8 and 11 machines has been converted for Z80 microprocessors. The compiler will run standalone on ZS0 systems with 16 kbytes memory, though the initial version to be released is for systems only with the CPM operating system, so a total of 20 kbytes memory is required. Runtime software totals about 4k, leaving 12k for programs and data (around 1200 statements). As versions of the compiler have been running for

M6800 peripherals the address and data buses of 8-bit organized systems such as the 6800. The functional configuration of the device is programmed via the data bus. Internal logic provides for control and handling of four individual chan-

Two new peripheral chips for 6800s have been announced by Motorola. The MC6844 is a DMA (direct memory access) controller which can transfer data directly between memory and peripheral controllers. It controls

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several years, very little trouble with bugs is expected. This one-pass compiler has all the main features of ALGOL-60 except that the calling of procedure parameters by name is limited to those cases in which the actual parameter is the name of a variable. The compiler produces compact intermediate code which requires about 5 words for an average statement. The runtime program contains a loader which reads the compiler output, placing the intermediate code in memory, and all the routines required to run the ALGOL program. A simple method of calling machine code is provided. This is used for all I/O transactions and makes it possible to adapt the system to use any peripherals to run under any operating system. Machine readable source code of the system is provided. (R H A (Minisystems) L/m/ted, 83 Gid/ey Way, Horspath, Oxford OX9 1 TO, UK)

1802 software Two software packages support the COSMAC CDP1800 microprocessor family. Both systems, the RAL-11 Level-II assembly language and the C-MAC macroassembler, are designed to cut development time. The RAL-II assembler, provided with the RCA's floppy-disk system, allows the assembly of COSMAC Level-II assembly language. Use of RAL-II shortens source code by about 35%, with the use of a class of special 'super-instructions'. Also available with the floppydisc system is the C-MAC macroassembler, which has macroinstruction definition, conditional assembly and 'program-build'. A range of fixed-point and floatingpoint binary arithmetic subroutines has also been made available. Among the packages is an implementation of the fixed-point subroutine on a 1 kbyte ROM. The software includes 31 subroutines including register save and mathematical companion operations, with arithmetic functions, format conversion and utility subroutines. The routines are all in 16-bit 2's-complement format. (RCA Limited/So/id

State-Europe, Sunbury-on- Thames, Midd/esex, Eng/and. Te/: Sunbury-onThames 85511. Telex: 24246)

54

A bo~Jk-size logic ana/yser costing $1295 can ~apture and rc¢otd ot~ 2.:" ,v~y~:/ ~hannels, permittiny the simultaneous recording of data from the addrc.~.~ and data buses, and status hTformatio/7 f?om many standard trlit; cJpto~ e,.so/ or bit-slice processor implementations. Up to 64 words o f m e m o o ~¢un be stored at external clock rates o f a m a x i m u m of 10 Mftx, /rom TTL ~omputib/e inputs. (Biomation Corporation, 4600 Old Ironside Drive, Santa Clan~, California 95050, USA)

The ',4' version o f AMI's $2000 single-chip microcomputer offers direct drive for vacuum fluorescent displays. Intended as a controller for low-end applications such as domestic appliances and automotive applications, the 52000A has onchip touch-panel interfacing, internal dock, and display decoding. /t can use 50 or 60 cycle line frequency for timing. (AM/Microsystem~ Limited, I08A Commercial Road, Swindon, Wi/tshire, UK. Tel: Swindon (0793) 31345. Telex: 449349)

microprocessors and microsystems