Cypress STK12C68 Manual De Usuario

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STK12C68
Document Number: 001-51027 Rev. **
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Pin Configurations
Pin Definitions
Pin Name
Alt
IO Type
Description
A
0
–A
12
Input
Address Inputs. Used to select one of the 8,192 bytes of the nvSRAM.
DQ
0
-DQ
7
Input or Output Bidirectional Data IO Lines. Used as input or output lines depending on operation.
WE
W
Input
Write Enable Input, Active LOW. When the chip is enabled and WE is LOW, data on the IO 
pins is written to the specific address location.
CE
E
Input
Chip Enable Input, Active LOW. When LOW, selects the chip. When HIGH, deselects the chip.
OE
G
Input
Output Enable, Active LOW. The active LOW OE input enables the data output buffers during 
read cycles. Deasserting OE HIGH causes the IO pins to tri-state.
V
SS
Ground
Ground for the Device. The device is connected to ground of the system.
V
CC
Power Supply
Power Supply Inputs to the Device
HSB
Input or Output Hardware Store Busy (HSB). When LOW, this output indicates a Hardware Store is in progress. 
When pulled low external to the chip, it initiates a nonvolatile STORE operation. A weak internal 
pull up resistor keeps this pin high if not connected (connection optional).
V
CAP
Power Supply
AutoStore
 
Capacitor. Supplies power to nvSRAM during power loss to store data from SRAM 
to nonvolatile elements.
Figure 1.  28-Pin SOIC/DIP and LLC