Memory Configuration
VL-486-4 Reference Manual
Configuration – 21
Memory Configuration
ROM C
ONFIGURATION
The on-board ROM sockets (U10 and U11) accept one or two 128Kx8, 256Kx8, or 512Kx8, 32
pin plastic
PLCC
or 32 pin J-lead ceramic part(s). An extractor tool (such as VersaLogic part
number 9685) is required to remove the rectangular
PLCC
device(s) without damage, and an
adapter may be required to program
PLCC
parts when using
EPROM
programmers that support
only 32-pin 0.6"
DIP
style packages.
The ROM contains BIOS and ROM disk data in DOS-based systems. In non-DOS-based
systems, the ROM contains the CPU initialization code and application code.
There are no configuration jumpers for the ROM sockets.
C
OMPATIBLE
ROM D
EVICES
The following (non exhaustive) list of memory devices can be used in the ROM sockets. All
parts must be 200 ns or less.
Caution
VersaLogic makes no representation of the suitability, reliability, or availability of
any of the memory devices.
Table 5: Compatible ROM/Flash Devices.
EPROM, UV Erasable (32-pin PLCC)
27C010
128K x 8
27C020
256K x 8
27C040
512K x 8
Available from Catalyst, Cypress, and Texas Instruments
Flash EPROM, 12 volt, Read-Only (32-pin PLCC)
28F010
128K x 8
28F020
256K x 8
Available from AMD, Catalyst, Intel, and Texas Instruments
Flash EPROM, 5 volt only, Read/Write (32-pin PLCC)
29F010
128K x 8
29F040
512K x 8
Available from AMD, Texas Instruments, and Atmel