2006-02-20

12

SCD55100A, SCD55101A, SCD55102A, SCD55103A, SCD55104A

Additional contrast enhancement is gained by shading the displays. Plastic band-pass filters with built-in louvers offer the next step up in

contrast improvement. Plastic filters can be improved further with anti-reflective coatings to reduce glare. The trade-off is fuzzy characters.

Mounting the filters close to the display reduces this effect. Take care not to overheat the plastic filter by allowing for proper air flow.

Optimal filter enhancements are gained by using circular polarized, anti-reflective, band-pass filters. The circular polarizing further

enhances contrast by reducing the light that travels through the filter and reflects back off the display to less than 1%.

Several filter manufacturers supply quality filter materials. Some of them are: Panelgraphic Corporation, W. Caldwell, NJ; SGL Homalite,

Wilmington, DE; 3M Company, Visual Products Division, St. Paul, MN; Polaroid Corporation, Polarizer Division, Cambridge, MA; Marks

Polarized Corporation, Deer Park, NY, Hoya Optics, Inc., Fremont, CA.

One last note on mounting filters: recessing displays and bezel assemblies is an inexpensive way to provide a shading effect in overhead

lighting situations. Several Bezel manufacturers are: R.M.F. Products, Batavia, IL; Nobex Components, Griffith Plastic Corp., Burlingame,

CA; Photo Chemical Products of California, Santa Monica, CA; I.E.E.–Atlas, Van Nuys, CA.

Microprocessor Interface

The microprocessor interface is through the serial port, SPI port or one out of eight data bits on the eight bit parallel port and also control

lines SDCLK and LOAD.

Power Up Sequence

Upon power up display will come on at random. Thus the display should be reset at power-up. The reset will set the Address Register to

Digit 0, User RAM is set to 0 (display blank) the Control Word is set to 0 (100% brightness with Lamp Test off) and the internal counters are

reset.

SCD5510XA Interface with Siemens/Intel 8031 Microprocessor

CC

V

40

39

16

11

10

P0.0

P3.6

P3.1

P3.0

P1.0

RST

8031

XTAL1

U1

XTAL2

CC

V

20

9

1

19

18

CC

V

20

Slave

CC

23

LOAD

CLK

SD

1

2

28

DATA

27

V

15

Master

13

69

14

19

SCD

20

16

CLK

1

SD

LOAD

26

27

28

DATA

23

14

13

9

16

SCD

19

15

22 µF

+

TAN

0.01 µF

IDCD5222