LSI LSI53C896, Technical Manual

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Flash ROM and Memory Interface Signals 3-19
3.4 Flash ROM and Memory Interface Signals
Table 3.15 describes the signals for the Flash ROM and Memory
Interface Signals group.
Table 3.15 Flash ROM and Memory Interface Signals
Name Bump Type Strength Description
MWE/ AC19 O 4 mA Memory Write Enable. This pin is used as a write
enable signal to an external flash memory.
MCE/ AA18 O 4 mA Memory Chip Enable. This pin is used as a chip enable
signal to an external EPROM or flash memory device.
MOE/_
TESTOUT Y18 O 4 mA Memory Output Enable. This pin is used as an output
enable signal to an external EPROM or flash memory
during read operations. It is also used to test the
connectivity of the LSI53C896 signals in the “AND-tree”
test mode. The MOE/_TESTOUT pin is only driven as
the test out function when the ZMODE bit (
Chip
Control 1 (CCNTL1) , bit 7) is set.
MAS0/ AC18 O 4 mA Memory Address Strobe 0. This pin is used to latch in
the least significant address byte (bits [7:0]) of an
external EPROM or flash memory. Since the LSI53C896
moves addresses eight bits at a time, this pin connects
to the clock of an external bank of flip-flops which are
used to assemble up to a 20-bit address for the external
memory.
MAS1/ AA17 O 4 mA Memory Address Strobe 1. This pin is used to latch in
the most significant address byte (bits [15:8]) of an
external EPROM or flash memory. Since the LSI53C896
moves addresses eight bits at a time, this pin connects
to the clock of an external bank of flip-flops which
assemble up to a 20-bit address for the external
memory.
MAD[7:0] Y19, AA19,
AC20,
AB20,
AA20,
AC22,
AB21,
AC23. I/O 4 mA Memory Address/Data Bus. This bus is used in
conjunction with the memory address strobe pins and
external address latches to assemble up to a 20-bit
address for an external EPROM or flash memory. This
bus will put out the least significant byte first and finish
with the most significant bits. It is also used to write data
to a flash memory or read data into the chip from
external EPROM/flash memory. These pins have static
pull-downs.
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