ROM Flash and Memory Interface Signals 3-11
3.6 ROM Flash and Memory Interface Signals

Tabl e 3.12 describes the ROM Flash and Memory Interface signals.

Table3.12 ROM Flash and Memory InterfaceSignals

Name PQFP BGA Type Strength Description
MWE/ 139 C7 O 4 mA Memo ry Write Enable. Thispinisusedasawrite
enable signal toan external flash memory.
MCE/ 141 A7 O 4mA Memory Chip Enable. Thispinisusedasachip
enable signal to an externalEEPROM or flash
memory device.
MOE/ 140 B7 O 4 mA Memory Output Enable. Thispinisusedasan
output enable signalto an external EEPROM or
flash memory during read operations.It is also
used to test the connectivityof the LSI53C875A
signals in test mode.
MAC/_
TESTOUT 77 L10 O 16 mA Memory Access Control. This pin can be
programmed to indicatelocal or system memory
accessed(non-PCI applications). It is also used to
test the connectivityof the LSI53C875A signals in
test mode.
MAS0/ 137 A8 O 4 mA MemoryAddr ess Strobe 0. This pin is used to
latchin the least significant address byte (bits [7:0])
of an external EEPROM or flashmemor y.Since
the LSI53C875A movesaddresses eight bits at a
time, this pin connectsto the clock of an external
bankof flip-flops which are used to assemble up to
a 20-bit address for the external memory.
MAS1/ 136 B8 O 4 mA MemoryAddr ess Strobe 1. This pin is used to
latch in the most significant address byte (b its
[15:8]) of an external EEPROM or flashmemor y.
Sincethe LSI53C875A moves addresses eight bits
at a time, this pin connectsto the clock of an
external bank of flip-flopswhich assemble up to a
20-bit address forthe external memory.