Data-communications fault finder An improved version of their microprocessor-based data-communication fault finder has been announced by Macwell Systems Ltd. Autotest II is based around the 6802 MPU and will be available in two case styles, either 19 in rack mounting or in a portable instrument case. The unit has been redesigned to meet the needs of computer centre staff and field
engineers. Features include a 20 character/line line printer, time of day and elapse time clocks, V.24 snap-shot facility when errors are detected, remote data logging access via RS232 output, and enhanced audio monitoring including transmit and receive carrier dBm displays. (Macwell Systems Ltd., The
Maltings, Sawbridgeworth, Herts. CM21 9JX, UK. Tel: (0279) 725650)
Data-communications fault finder
Statistical multiplexers The Series II range of microprocessor-controlled statistical multiplexers/data concentrators from Timeplex is claimed to maintain data networkcontrol with a high level of error correction, while reducing the basic communication cost. Microprocessor-based, and conforming to X.25, tl~e Series II range offers a variety ot; specifications. Moder M.400 has four asynchronous data channels, each capable of operating at 4 800 bit/s, and a datalink operating asynchronously at speeds of up to 9 600 bit/s. The M24C Model includes a power supply, main module and a fourchannel expander module, and has the facility to add data channels in groups of four to a maximum of 24 plus a total buffer memory of 112 kbyte. The recently announced Alpha Star network management system, a floppy-disc based microcomputer,
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Monitoring Network users operating non-Intertel modems can now use EMS-One, an automated system for monitoring and controlling data communications networks. RAP1000, which has been accepted by British Telecom for operation on the public switched network, can interface any modem to an Intertel system and is transparent to all user data communications. The automatic monitoring mode continually monitors every line and drop in the system while normal data communications continues. The manual diagnostic mode enables the additional specialized testing of faults without affecting the remainder of the system. The third mode, automatic preventive maintenance, automatically tests the complete system at programmed times during off h o u rs. All network control functions can be supported on any 1 200, 2 400 and 4 800 bit/s modems and most 9 600 bit/s modems (Data Logic Ltd.
29 Marylebone Road, London NWl, UK. Tel: 01-486 7288) []
can collect, store and generate management information on the network activity from up to 16 microplexer systems. By using simple commands, the user can look at both local and remote multiplexers, remove the required information and have it stored or printed out. Typically, the system will report traffic density, input buffer usage for all channels, hardware and firmware status of each module, and the current selection of each programmable data channel parameter. The Alpha Star supports up to three floppy-disc drives, one containingthe operating system and the other two supplying storage of up to 81 kbyte each. A real-time clockaids the monitoringwith an indication of the time and date of each transaction on an online display and management reports. (Timeplex Ltd.
Printed or typewritten material can be converted for immediate system input by an omnifont text digitizing service using magnetic tape or a communications line totransmitthe data to another processor. The UK service is based on the Kurzweil data entry machine, which is trained to read any character set or combination thereof, including Greek or Cyrillic, by analysing the geometric and topological features of each character and comparing these to the 'multiproperty descriptors' it builds up in its memory. The technique permits a subtle distinction to be made between similar images such as a lower case 'l' and the figure '1'. (CTP, 6 White Horse
77 Boston Manor Road, Brentford, Middx, UK. Tel: 01-568 1941) []
Street, Mayfair, London, W17 7LA, UK. Tel: 01-499 2262) []
Text digitizer
computer communications