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6 rom flash and memory interface signals, Table 3.12 rom flash and memory interface signals, Rom flash and memory interface signals – LSI 53C875A User Manual

Page 87: Rom flash and memory interface, Signals

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ROM Flash and Memory Interface Signals

3-11

3.6 ROM Flash and Memory Interface Signals

Table 3.12

describes the ROM Flash and Memory Interface signals.

Table 3.12

ROM Flash and Memory Interface Signals

Name

PQFP

BGA

Type Strength Description

MWE/

139

C7

O

4 mA

Memory Write Enable. This pin is used as a write
enable signal to an external flash memory.

MCE/

141

A7

O

4 mA

Memory Chip Enable. This pin is used as a chip
enable signal to an external EEPROM or flash
memory device.

MOE/

140

B7

O

4 mA

Memory Output Enable. This pin is used as an
output enable signal to an external EEPROM or
flash memory during read operations. It is also
used to test the connectivity of the LSI53C875A
signals in test mode.

MAC/_
TESTOUT

77

L10

O

16 mA

Memory Access Control. This pin can be
programmed to indicate local or system memory
accessed (non-PCI applications). It is also used to
test the connectivity of the LSI53C875A signals in
test mode.

MAS0/

137

A8

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 EEPROM or flash memory. Since
the LSI53C875A 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/

136

B8

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 EEPROM or flash memory.
Since the LSI53C875A 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.