Sanyo LC7985NA LCD Help????

I need help with an LCD problem…I am running a 20x2 dot matrix LCD with the Sanyo LC7985NA controller. The unit also has a Seiko chip SED1181FLA. I have the screen powered up and it has (20) solid 5x7 dots only on the top row. I tried using the prewritten LCD codes with no luck.

I tested the pinouts by checking continuity and found all GND’s and +5V. I also found DB0-7, RS, RW, & E.


Pin 1 - GND
::::Attached to GND

Pin 2 - LED GND (this is a two-colored external LED which I know how to control)
::::Attached to GND

Pin 3 - +5V Green LED
::::Attached to +5V

Pin 4 - + 5V Red LED
::::Unattached for now

Pin 5 - DB4
::::Attached to Arduino Pin 5

Pin 6 - DB5
::::Attached to Arduino Pin 4

Pin 7 - DB6
::::Attached to Arduino Pin 3

Pin 8 - DB7
::::Attached to Arduino Pin 2

Pin 9 - E: Execution start input to R/W
::::Attached to Arduino Pin 11

Pin 10 - RS
::::Attached to Arduino Pin 12

Pin 11 - Sanyo V5, Seiko VSSH
::::Attached to GND

Pin 12 - Sanyo VDD, Seiko VDD
::::Attached to +5V

Pin 13 - Sanyo R/W, DB0, DB1, DB2, DB3, Seiko VSS
::::Attached to GND

Pin 14 - GND
::::Attached to GND

Any ideas of what could be wrong?


My crystal ball is out of commission. I can’t seem to be able to see your code or your interconnections. All I can tell is that you have the power connected correctly and that your LCD controller is not initialized properly.