emWin: LCD667xx driver

Supported hardware

Controllers

This driver has been tested with the following LCD controllers

Himax HX8301, HX8312
Hitachi HD66766, HD66772, HD66789
Ilitec ILI09320, ILI9161, ILI9220
Samsung S6D0110A, S6D0117, S6D0129
Sharp LR38825, LCY-A06003
Sitronix ST7712
Renesas R61509, R63401
Solomon SSD1289
Toshiba JBT6K71
MagnaChip D54E4PA7551
Novatek NT39122
Sitronix ST7712

Bits per pixel

Supported color depth is 16 bpp.

Interfaces

The driver supports 8-bit parallel (simple bus) and 3 pin SPI interface. Default mode is 8-bit parallel.

Display data RAM organization

The picture above shows the relation between the display memory and the SEG and COM lines of the LCD.

Additional RAM requirements of the driver

This LCD driver can be used with and without a display data cache, containing a complete copy of the contents of the LCD data RAM. The amount of memory used by the cache is: LCD_XSIZE x LCD_YSIZE x 2 bytes. Using a cache is only recommended if a lot of drawing operations uses the XOR drawing mode. A cache would avoid reading the display data in this case. Normally the use of a cache is not recommended. The driver can be used with a write buffer used for drawing multiple pixels of the same color. If multiple pixels of the same color should be drawn the driver first fills the buffer and then executes only one time the macro LCD_WRITEM_A1 to transfer the data to the display controller. The default buffer size is 500 bytes.

Additional driver functions

None.

Hardware configuration

This driver accesses the hardware with a simple bus interface or with a 3 pin SPI interface. The following table lists the macros which must be defined for hardware access:

Macro	Explanation
LCD_INIT_CONTROLLER	Initialization sequence for the LCD controller.
LCD_NUM_DUMMY_READS	Number of required dummy reads if a read operation should be executed. The default value is 2. If using a serial interface the display controllers HD66766 and HD66772 need 5 dummy reads.
LCD_SERIAL_ID	If using the serial interface this macro defines the ID signal of the device ID code. It should be 0 (default) or 1.
LCD_USE_SERIAL_3PIN	Should be set to 1 if the serial interface is used. Default is 0.
LCD_USE_PARALLEL_16	Should be set to 1 if the 16 bit parallel interface is used. Default is 0.
LCD_WRITE_BUFFER_SIZE	Using a write buffer increases the performance of the driver. If multiple pixels should be written with the same color the driver first fills the buffer and then writes the contents of the buffer with one execution of the macro LCD_WRITEM_A1 instead of multiple executions. The default buffer size is 500 bytes.
LCD_READM_A1	Read multiple bytes from display controller with RS-line high.
LCD_WRITEM_A1	Write multiple bytes to display controller with RS-line high.
LCD_WRITEM_A0	Write multiple bytes to display controller with RS-line low.

The driver initializes the ’Driver Output Mode’ and ’Entry Mode’ register itself. The user does not need to initialize this registers in the LCD_INIT_CONTROLLER macro.

Additional configuration switches

None.

Special requirements

None.