SSD1818

Maximum ratings are those values beyond which damages to the device may occur. Functional operation should be restricted to
the limits in the Electrical Characteristics tables or Pin Description section

This device contains circuitry to protect the inputs against damage due to high static voltages or electric fields; however, it is advised that normal precautions to be taken to avoid application of any voltage higher than maximum rated voltages to this high impedance circuit. For proper operation it is recommended that V_in and V_out be constrained to the range V_SS < or = (V_in or V_out) < or = V_DD. Reliability of operation is enhanced if unused input are connected to an appropriate logic voltage level (e.g., either V_SS or V_DD). Unused outputs must be left open. This device may be light sensitive. Caution should be taken to avoid exposure of this device to any light source during normal operation. This device is not radiation protected.

This module SSD1818 determines whether the input signal is interpreted as data or command. Input is directed to this module based on the input of the D/C pin.

If the D/ C pin is high, input is written to Graphic Display Data RAM (GDDRAM). If it is low, the input at D7-D0 is interpreted as a Command. SSD1818 will be decoded and written to the corresponding command register.

The parallel interface of SSD1818 consists of 8 bi-directional data pins (D7-D0), R/W (WR ), D/C , E/(RD), CS1 and CS2.

R/W (WR ) input high indicates a read operation from the Graphic Display Data RAM (GDDRAM) or the status register. In order to match the operating frequency of the GDDRAM with that of the MCU, pipeline processing is internally performed which requires the insertion of a dummy read before the first actual display data read. This is shown in Figure 3.