Acorn FileStore E01, Руководство по обслуживанию

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Chapter 2 E01S Specification
FileStore Service Manual 53
2. E01S Specification
This chapter gives details of the main features of the E01S, including electrical specifications for
the interface ports.
2.1 General specification
The E01S unit has two 3.5‖ floppy disc drives, a switch mode power supply unit (psu) and a
fileserver disc drive pcb. The psu su5V and +12V rails and meets BS5850 (IEC380).
The file server disc drive pcb contains 64k of RAM and ROM (one 27512 EPROM), a Real Time
Clock with battery backup, a floppy disc controller, an Econet Interface and a printer interface. The
microprocessor is a 65C102 device, running at 2MHz, which provides all the processing required.
The ROM contains operating system, filing system and Econet code needed to run the file server.
The 64k of RAM and ROM are never in the memory map at the same time. On power up the ROM
is read and it copies its file server code into in RAM. At the completion of this exercise the memory
map is almost totally resident in RAM.
A Real Time Clock circuit incorporating the 146818 RTC is used to provide the information to
allow date stamping of files and also to offer the facility of the Time and Date commands to users.
The RTC is battery backed-up by a rechargeable nickel cadmium cell.
The Econet Interface is based upon the Acorn Econet module. An Econet clock is generated if no
clock is present.
The floppy disc interface is based upon the 2793 disc controller to provide an SA400 interface.
A Centronics-compatible printer interface is driven by a VIA which also reads the door flap switch
in order to inform the processor

when a disc is about to be changed

whether to power up in user mode or maintenance mode.
A front door flap switch (an optical sensor) is used to inform the processor when a disc is about to
be changed and whether to power up in user mode or maintenance mode.
During normal operation, when a user opens the door flap, the processor needs to save the complete
disc maps (held in memory) on the discs before they are removed. It is therefore essential that
before removing a disc, the user first waits until the drive motors have stopped, indicating that the
maps have been stored.
FileStore will normally only accept network filing system commands. To format discs and issue
direct commands to the disc, you must put FileStore into a different mode; ―maintenance mode‖.
(This is to prevent users erasing and formatting discs by mistake.) To enter maintenance mode,
either power up with the access flap open, or use the *FSMODE M command from a user station
(see the FileStore Network Manager‘s Guide for further details).
For connection to the E40S or E60S units, a FileStore expansion bus interface, similar to the BBC
microcomputer 1MHz bus interface, but running at 2MHz, is fitted to the rear of the unit.
A terminator plug is supplied with the unit and is used to terminate the FileStore expansion bus
when the E01S is connected to a FileStore E40S or E60S hard disc unit.