HDSP-2131 Datasheet, PDF (9/16 Pages) Agilent(Hewlett-Packard) – Eight Character 5.0 mm (0.2 inch) Glass/Ceramic Intelligent 5 X 7 Alphanumeric Displays for Military Applications

Electrical Description
Pin Function
RESET (RST, Pin 5)
FLASH (FL, Pin 27)
ADDRESS INPUTS
(A₀-A₄, Pins 28-32)
Description
Reset initializes the display.
FL low indicates an access to the Flash RAM and is unaffected by the
state of address lines A₃-A₄.
Each location in memory has a distinct address. Address inputs (A₀-A₂)
select a specific location in the Character RAM, the Flash RAM or a
particular row in the UDC (User-Defined Character) RAM. A₃-A₄ are used to
select which section of memory is accessed. Table 1 shows the logic levels
needed to access each section of memory.
Table 1. Logic Levels to Access Memory
FL A₄ A₃ Section of Memory
0 X X Flash RAM
A₂ A₁ A₀
Character Address
1 0 0 UDC Address Register Don't Care
1 0 1 UDC RAM
Row Address
1 1 0 Control Word Register Don't Care
1 1 1 Character RAM
Character Address
CLOCK SELECT
(CLS, Pin 1)
CLOCK INPUT/OUTPUT
(CLK, Pin 2)
WRITE (WR, Pin 3)
CHIP ENABLE (CE, Pin 4)
READ (RD, Pin 6)
DATA Bus (D₀-D₇,
Pins 11-14, 19-22)
GND_(SUPPLY) (Pin 17)
GND_(LOGIC) (Pin 18)
V_DD(POWER) (Pin 16)
This input is used to select either an internal (CLS = 1) or external
(CLS = 0) clock source.
Outputs the master clock (CLS = 1) or inputs a clock (CLS = 0) for slave
displays.
Data is written into the display when the WR input is low and the CE input
is low.
This input must be at a logic low to read or write data to the display and
must go high between each read and write cycle.
Data is read from the display when the RD input is low and the CE
input is low.
The Data bus is used to read from or write to the display.
This is the analog ground for the LED drivers.
This is the digital ground for internal logic.
This is the positive power supply input.
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