- Email: [email protected]
Z8001 put on VME board by UK company
Chip controls token access in LANs The WD2840 controller chip from Western Digital has been designed for token access control in local-area networks. The 48-pin chip supports coaxial cable, fibre optics and microwave links. It operates at 1.1 Mbits/s with up to 254 nodes per network. A controller/formatter device in a single 28-pin package, the WD1770, has also been introduced. It includes digital data separation, write pcecompensation and motor-on control. The floppy disc controller is software compatible with the WD179X family. The WD2840 provides global addressing fol broadcasting data. The internal layout includes a serial communications subsystem, a two-channel direct memory access controller and a microprocessor, with its own ROM and RAM. The chip interfaces to the medium via a modem and to the host via the
CPU bus. A buffer chaining scheme is used. With the WD2840 the CPU is not needed for network initialization, addressing, coordination, data transmission, acknowledgements and diagnostics. The WD1770 uses a +5 V power supply. It can control single- and double-density 51/~-in drives with sector lengths from 128 bytes to 1 kbyte. There is a choice of step rates (up to 2 ms). The motor-on signal can be programmed from the command register. The device is intended for home computers or small business sytems.
(Western Digital Corp., 28-30 Upper High Street, Epsom, Surrey KTI9 8,4 H, UK. Tel: (03 72 7) 42178. Telex: 925 796 WDDPSC G. UK distributors: Pronto Electronic Systems Ltd, 466--478 Cranbrook Road, Gants Hill, Ilford, Essex IG2 6LE, UK. Tel: 01554 6222. Telex: 8754213)
Z8001 put on VME board by UK company The ARC 8000 single-board computer from Arcom Control Systems of the UK can be used for VME bus applications. The microcomputer is a Z8001. The ARC 8000 has onboard RAM and EPROM as well as serial and parallel I/O interfaces. It can also be combined with analogue inputand output boards. Two RS232 channels link the board to printers and other peripheral devices. The 24 I/O lines can be used with other boards for A/D or D/A conversion, digital and power inputs and/or outputs, IEEE-488 interfacing and EPROM programming. The unit can act as a VME bus master. A range of processor speeds from 4 MHz upwards is available. A system clock option is available on the 4 MHz and 8 MHz versions. A 4 kbyte monitor in EPROM is included with the board. This allows memory and register examination and modification, breakpoint setting, single stepping, EPROM programming, and downloading from host systems. The board measures 160 mm x 233 mm. A cheaper version, not for VME bus applications, is also available.
vol 7 no 7 sept 1983
This is the ARC 8000S; it has buffered address/data lines taken to the Eurocard Connector. (Arcom Control
Systems Ltd, Unit 6, Robert Davis Court, Nuffield Road Industrial Estate, Chesterton, Cambs, UK. Tel: (0223) 322642. UK distributor: Hi-Tek Distribution Ltd, Trafalgar Way, Bar Hill, Cambs CB3 85Q, UK. Tel: (0954) 81931. Telex: 817347)
Realtime clock circuit uses 32 kHz crystal The MEM M3000 realtime clock circuit has been announced by Altek Microcomponents. The only external component it needs for operation is a 32 kHz crystal. The circuit is contained in a 16-pin dual-in-line package. Timing information is stored in a 16 x 8 RAM. An 8-bit status word in the RAM stores the mode of operation programmed by the user. Address and data words are 4-bit. They are multiplexed over TTLcompatible I/O pins. Independent watch, alarm and timer functions are provided in a 4-~oit BCD format. A 'busy' output can be used as a 1 Hz strobe for display control. The standby current of the CMOS circuitry is 20/~A. The circuitry uses an external 3 V battery. The operating current from a +5 V supply is 4.0/~A. The watch function counts seconds up to a total of 99 years. It indicates the day of the week and the week number and adjusts automatically to leap years. The M3000 can be used for processor-controlled instrumentation, event recorders, word processors, taxi meters, business machines, home computers and point-of-sale terminals, says Altek. (Altek Microcomponents
Ltd, 22 Market Place, Wokingham, Berks RGl l IAP, UK. Tel: (0734) 791579. Telex: 849010)
IBM PC gets Winchesters from 5 to 15 Mbyte A hard-disc subsystem for the IBM personal computer has been announced by CMC International in the USA. The Targa II comes in three models. The first is a single-drive-only machine with three formatted storage capacities of 5 Mbytes, 10 Mbytes or 15 Mbytes. The second has the same configuration, with an extra slot for a second drive. In the third model the user can install five more IBM expansion cards. The units begin at $1490 for the model 1 with a 5 Mbyte capacity and go up to $2445 for the model 3 with 15 Mbytes. (CMC International, CMC
A venue N E, Bellevue, WA 98005, USA. Tel: (206) 885-1600. Telex: 152556 TAC)
International Building, 1720 130th
Winchesters for IBMs
343
CPU bus. A buffer chaining scheme is used. With the WD2840 the CPU is not needed for network initialization, addressing, coordination, data transmission, acknowledgements and diagnostics. The WD1770 uses a +5 V power supply. It can control single- and double-density 51/~-in drives with sector lengths from 128 bytes to 1 kbyte. There is a choice of step rates (up to 2 ms). The motor-on signal can be programmed from the command register. The device is intended for home computers or small business sytems.
(Western Digital Corp., 28-30 Upper High Street, Epsom, Surrey KTI9 8,4 H, UK. Tel: (03 72 7) 42178. Telex: 925 796 WDDPSC G. UK distributors: Pronto Electronic Systems Ltd, 466--478 Cranbrook Road, Gants Hill, Ilford, Essex IG2 6LE, UK. Tel: 01554 6222. Telex: 8754213)
Z8001 put on VME board by UK company The ARC 8000 single-board computer from Arcom Control Systems of the UK can be used for VME bus applications. The microcomputer is a Z8001. The ARC 8000 has onboard RAM and EPROM as well as serial and parallel I/O interfaces. It can also be combined with analogue inputand output boards. Two RS232 channels link the board to printers and other peripheral devices. The 24 I/O lines can be used with other boards for A/D or D/A conversion, digital and power inputs and/or outputs, IEEE-488 interfacing and EPROM programming. The unit can act as a VME bus master. A range of processor speeds from 4 MHz upwards is available. A system clock option is available on the 4 MHz and 8 MHz versions. A 4 kbyte monitor in EPROM is included with the board. This allows memory and register examination and modification, breakpoint setting, single stepping, EPROM programming, and downloading from host systems. The board measures 160 mm x 233 mm. A cheaper version, not for VME bus applications, is also available.
vol 7 no 7 sept 1983
This is the ARC 8000S; it has buffered address/data lines taken to the Eurocard Connector. (Arcom Control
Systems Ltd, Unit 6, Robert Davis Court, Nuffield Road Industrial Estate, Chesterton, Cambs, UK. Tel: (0223) 322642. UK distributor: Hi-Tek Distribution Ltd, Trafalgar Way, Bar Hill, Cambs CB3 85Q, UK. Tel: (0954) 81931. Telex: 817347)
Realtime clock circuit uses 32 kHz crystal The MEM M3000 realtime clock circuit has been announced by Altek Microcomponents. The only external component it needs for operation is a 32 kHz crystal. The circuit is contained in a 16-pin dual-in-line package. Timing information is stored in a 16 x 8 RAM. An 8-bit status word in the RAM stores the mode of operation programmed by the user. Address and data words are 4-bit. They are multiplexed over TTLcompatible I/O pins. Independent watch, alarm and timer functions are provided in a 4-~oit BCD format. A 'busy' output can be used as a 1 Hz strobe for display control. The standby current of the CMOS circuitry is 20/~A. The circuitry uses an external 3 V battery. The operating current from a +5 V supply is 4.0/~A. The watch function counts seconds up to a total of 99 years. It indicates the day of the week and the week number and adjusts automatically to leap years. The M3000 can be used for processor-controlled instrumentation, event recorders, word processors, taxi meters, business machines, home computers and point-of-sale terminals, says Altek. (Altek Microcomponents
Ltd, 22 Market Place, Wokingham, Berks RGl l IAP, UK. Tel: (0734) 791579. Telex: 849010)
IBM PC gets Winchesters from 5 to 15 Mbyte A hard-disc subsystem for the IBM personal computer has been announced by CMC International in the USA. The Targa II comes in three models. The first is a single-drive-only machine with three formatted storage capacities of 5 Mbytes, 10 Mbytes or 15 Mbytes. The second has the same configuration, with an extra slot for a second drive. In the third model the user can install five more IBM expansion cards. The units begin at $1490 for the model 1 with a 5 Mbyte capacity and go up to $2445 for the model 3 with 15 Mbytes. (CMC International, CMC
A venue N E, Bellevue, WA 98005, USA. Tel: (206) 885-1600. Telex: 152556 TAC)
International Building, 1720 130th
Winchesters for IBMs
343