X86C64 Datasheet, PDF (2/12 Pages) Xicor Inc. – E2 Micro-Peripheral

X86C64
PIN DESCRIPTIONS
Address/Data (A/D₀–A/D₇)
Multiplexed low-order addresses and data. The ad-
dresses flow into the device while AS is LOW. After AS
transitions from a LOW to HIGH the addresses are
latched. Once the addresses are latched these pins input
data or output data depending on DS, R/W, and CE.
Addresses (A₈–A₁₂)
High order addresses flow into the device when AS = V_IL
and are latched when AS goes HIGH.
Chip Enable (CE)
The Chip Enable input must be HIGH to enable all read/
write operations. When CE is LOW and AS is HIGH, the
X86C64 is placed in the low power standby mode.
Data Strobe (DS)
When used with a Z8 the DS input is tied directly to the
DS output of the microcontroller.
Read/Write (R/W)
When used with a Z8 the R/W input is tied directly to the
R/W output of the microcontroller.
Address Strobe (AS)
Addresses flow through the latches to address decoders
when AS is LOW and are latched when AS transitions
from a LOW to HIGH.
Device Select (SEL)
Must be connected to V_SS.
Write Control (WC)
The Write Control allows external circuitry to abort a
page load cycle once it has been initiated. This input is
useful in applications in which a power failure or proces-
sor RESET could interrupt a page load cycle. In this
case, the microcontroller might drive all signals HIGH,
causing bad data to be latched into the E²PROM. If the
Write Control input is driven HIGH (before t_TBLC Max)
after Read/Write (R/W) goes HIGH, the write cycle will
be aborted.
When WC is LOW (tied to V_SS) the X86C64 will be
enabled to perform write operations. When WC is HIGH
normal read operations may be performed, but all at-
tempts to write to the device will be disabled.
PIN CONFIGURATION
NC
A12
NC
NC
WC
SEL
A/D0
A/D1
A/D2
A/D3
A/D4
VSS
DIP/SOIC
1
24
2
23
3
22
4
21
5
20
6
19
X86C64
7
18
8
17
9
16
10
15
11
14
12
13
VCC
R/W
AS
A8
A9
A11
DS
A10
CE
A/D7
A/D6
A/D5
3819 FHD F01
PIN NAMES
Symbol
AS
A/D₀–A/D₇
A8–A12
DS
R/W
CE
WC
SEL
VSS
VCC
Description
Address Strobe
Address Inputs/Data I/O
Address Inputs
Data Strobe Input
Read/Write Input
Chip Enable
Write Control
Device Select—Connect to V_SS
Ground
Supply Voltage
3819 PGM T01
2