Specifications

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2.3.4 Byte-Wide Memory Sockets
The Little Board/286 has two onboard byte-wide memory device sockets that can accommodate a
variety of EPROM and nonvolatile RAM (NOVRAM) devices, used for simple program storage
or as "Solid State Disk" (SSD) drives.
Some of the byte-wide devices which can be used in these sockets are shown in Table 2-6. The
NOVRAM cartridges described in the table connect with a short ribbon cable (Dallas P/N
DS9000) to a byte-wide socket: U32 or U33. Devices used in these sockets must be 300 nS (or
faster), on both 12 MHz and 16 MHz boards.
Table 2-6. Byte-Wide Device Compatibility
DEVICE TYPE SIZE PART NUMBER
Normal EPROM (*) 8K bytes Intel 2764
Normal EPROM (*) 16K bytes Intel 27128
Normal EPROM 32K bytes Intel 27256
Page-addr EPROM 128K bytes Intel 27011
Static RAM (*) 8K bytes Hitachi 6264
Static RAM 32K bytes Hitachi 62256
28-pin NOVRAM 32K bytes Dallas DS1230
NOVRAM Cartridges 32K-512K bytes Dallas DS1217
(*) Note: 8K byte EPROM's and static RAM's will appear four times,
and 16K byte EPROM's two times, within the 32K address window
of the socket.
Direct Program Access
The memory devices installed in U32 and U33 can be accessed directly by your application
software, provided the program knows about them. Note that the byte-wide sockets must be
enabled prior to use using the SETUP configuration program (see Chapter 3) or under control of
your application program (see Chapter 4).
The byte-wide memory sockets reside at the following memory addresses:
n U32 is at D0000h
n U33 is at D8000h
Through a technique known as a "ROM-BIOS extension", it is possible to have the system run
its entire application from byte-wide socket memory devices, instead of from disk drives. This is
discussed in Ampro application note AAN-8702. Be sure the sockets are enabled, as mentioned
above, if they are to be used with ROM-BIOS extensions.
Solid State Disk (SSD) Drives
The optional Ampro Solid State Disk (SSD) Support Software, allows you to configure a Little
Board/286 system to boot, operate, and even store data using one or two EPROM and/or
NOVRAM solid-state "drives" under control of the DOS (version 3.3 or later) operating system.
No custom programming is required, other than use of the development tools provided in the
SSD Support Software.