Force Computers SYS68K/CPU-40, User Manual

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SECTION 1 INTRODUCTION
2-7
2.3 The System EPROM
The CPU board offers two 40-pin EPROM sockets for the installation of two 16-bit wide EPROM devices.
The EPROMs present a full 32-bit data path to the processor enabling maximum performance. The
following devices are supported in the system EPROM area:
Supported Device Types in the System EPROM Area:
Organization Total Memory Capacity
64K x 16 256 Kbytes
128K x 16 512 Kbytes
256K x 16 1 Mbyte
512K x 16 2 Mbytes
2.4 The Local SRAM
The CPU board contains a 128K * 8 bit SRAM. Battery backup is provided via the on-board battery or the
5VSTDBY line.
2.5 The Local FLASH EPROM
A 128 Kbyte FLASH EPROM is included on the base board of the CPU-40 which can be used as additional
data backup under conditions of power down for long periods. FLASH EPROM is ideal to hold details of
the board status, such as software revision or user data which is to be kept permanently.
2.6 The Boot EPROM
The CPU board contains, in addition to the two system EPROMs, a single boot EPROM to boot the local
microprocessor, initialize all I/O devices and program the board-dependent functions of the FGA-002. All
basic initialization of the I/O devices and the FGA-002 are made through the boot EPROM.
In addition, the boot EPROM contains user utility routines, which may be called out of the user's application
program. These routines provide easy software access to the functionality of the FGA-002 (DMA controller,
FORCE Message Broadcast, Interrupt Management, etc.).