Display Driver

Table of Contents

• GLCDC HAL Module Introduction
  • GLCDC HAL Module Features
  • GLCDC Hardware support details
• GLCDC HAL Module APIs Overview
• GLCDC HAL Module Operational Overview
  • GLCDC HAL Module Important Operational Notes and Limitations
    • GLCDC HAL Module Operational Notes
    • GLCDC HAL Module Limitations
• Including the GLCDC HAL Module in an Application
• Configuring the GLCDC HAL Module
  • GLCDC HAL Module Clock Configuration
  • GLCDC HAL Module Pin Configuration
• Using the GLCDC HAL Module in an Application

GLCDC HAL Module Introduction

The Graphics LCD Controller (GLCDC) HAL module provides a high-level API for graphics display applications and uses the Graphics LCD Driver peripheral on the Synergy MCU. A user-defined callback can be created to handle frame buffer switching and underflow detection.

GLCDC HAL Module Features

The GLCDC HAL supports the following features:

• Supports LCD panels with RGB interface (up to 24 bits) and sync signals (HSYNC, VSYNC, and Data Enable (optional))
• Supports various color formats for input graphics planes (RGB888, ARGB888, RGB565, ARGB1555, ARGB4444, CLUT8, CLUT4, CLUT1)
• Supports the Color Look-Up Table (CLUT) usage for input graphics planes with 512 words (32 bits/word)
• Supports various color formats for output (RGB888, RGB666, RGB565, Serial RGB)
• Can input two graphics planes on top of the background plane and blend them on the screen
• Generates a dot clock to the panel. The clock source is selectable from internal or external (LCD_EXTCLK)
• Supports brightness adjustment, contrast adjustment, and gamma correction
• Supports GLCDC interrupts to handle frame buffer switching or underflow detection

GLCDC HAL Module Block Diagram

GLCDC Hardware support details

The following hardware features are, or are not, supported by the SSP for the GLCDC:

Legend:

 

Symbol	Meaning
✓	Available (Tested)
⌧	Not Available (Not tested/not functional or both)
N/A	Not supported by MCU

 

MCU Group	Single Color Background Plane	Graphics 1 Plane	Graphics 2 Plane	Support 16 bit per pixel graphics	Support 32 bit per pixel graphics	Support 1-bit LUT
S124	N/A	N/A	N/A	N/A	N/A	N/A
S128	N/A	N/A	N/A	N/A	N/A	N/A
S1JA	N/A	N/A	N/A	N/A	N/A	N/A
S3A1	N/A	N/A	N/A	N/A	N/A	N/A
S3A3	N/A	N/A	N/A	N/A	N/A	N/A
S3A6	N/A	N/A	N/A	N/A	N/A	N/A
S3A7	N/A	N/A	N/A	N/A	N/A	N/A
S5D3	N/A	N/A	N/A	N/A	N/A	N/A
S5D5	N/A	N/A	N/A	N/A	N/A	N/A
S5D9	✓	✓	✓	✓	✓	✓
S7G2	✓	✓	✓	✓	✓	✓

 

MCU Group	Support 4-bit LUT	Support 8-bit LUT	Support All Pixel formats	Supports Alpha Blending	Video Signal Timing Adjustment	Supports All Output Data formats
S124	N/A	N/A	N/A	N/A	N/A	N/A
S128	N/A	N/A	N/A	N/A	N/A	N/A
S1JA	N/A	N/A	N/A	N/A	N/A	N/A
S3A1	N/A	N/A	N/A	N/A	N/A	N/A
S3A3	N/A	N/A	N/A	N/A	N/A	N/A
S3A6	N/A	N/A	N/A	N/A	N/A	N/A
S3A7	N/A	N/A	N/A	N/A	N/A	N/A
S5D3	N/A	N/A	N/A	N/A	N/A	N/A
S5D5	N/A	N/A	N/A	N/A	N/A	N/A
S5D9	✓	✓	✓	✓	✓	✓
S7G2	✓	✓	✓	✓	✓	✓

 

MCU Group	Supports All Dithering Modes	Support output of VSYNC, HSYNC **and Horizontal Data Enable**	Supports Brightness and Contrast	Supports Gamma Correction
S124	N/A	N/A	N/A	N/A
S128	N/A	N/A	N/A	N/A
S1JA	N/A	N/A	N/A	N/A
S3A1	N/A	N/A	N/A	N/A
S3A3	N/A	N/A	N/A	N/A
S3A6	N/A	N/A	N/A	N/A
S3A7	N/A	N/A	N/A	N/A
S5D3	N/A	N/A	N/A	N/A
S5D5	N/A	N/A	N/A	N/A
S5D9	✓	✓	✓	✓
S7G2	✓	✓	✓	✓

GLCDC HAL Module APIs Overview

The GLCDC HAL module defines APIs for opening, closing, starting, stopping and controlling the display of information on an LCD panel. A complete list of the available APIs, an example API call and a short description of each can be found in the following table. A table of status return values follows the API summary table.

GLCDC HAL Module API Summary

Function Name	Example API Call and Description
open	g_display.p_api->open (g_display.p_ctrl, g_display.p_cfg); Open display device.
close	g_display.p_api->close (g_display.p_ctrl); Close display device.
start	g_display.p_api->start(g_display.p_ctrl); Display start.
stop	g_display.p_api->stop(g_display.p_ctrl); Display stop.
layerChange	g_display.p_api->layerChange(g_display.p_ctrl, &layercng) Change layer parameters at runtime.
correction	g_display.p_api->correction(g_display.p_ctrl, &display_correction) Color correction.
clut	g_display.p_api->clut(g_display.p_ctrl, &clut) Set CLUT for display device.
statusGet	g_display.p_api->statusGet(g_display.p_ctrl, &status) Get status for display device.
versionGet	g_display.p_api->versionGet(&version) Retrieve the API version using the version pointer.

Note

For more complete descriptions of operation and definitions for the function data structures, typedefs, defines, API data, API structures, and function variables, review the SSP User's Manual API References for the associated module.

Status Return Values

Name	Description
SSP_SUCCESS	API call successful.
SSP_ERR_ASSERTION	Parameter has invalid value.
SSP_ERR_INVALID_ARGUMENT	Invalid parameter in the argument.
SSP_ERR_HW_LOCKED	GLCDCC resource is locked.
SSP_ERR_CLOCK_GENERATION	Dot clock cannot be generated from clock source.
SSP_ERR_INVALID_TIMING_SETTING	Invalid panel timing parameter.
SSP_ERR_INVALID_LAYER_SETTING	Invalid layer setting found.
SSP_ERR_INVALID_LAYER_FORMAT	Invalid format is specified.
SSP_ERR_INVALID_GAMMA_SETTING	Invalid gamma correction setting found.
SSP_ERR_NOT_OPEN	The function call is performed when the driver state is not equal to DISPLAY_STATE_CLOSED.
SSP_ERR_INVALID_UPDATE_TIMING	A function call is performed when the GLCDC is updating register values internally.
SSP_ERR_INVALID_MODE	Function call is performed when the driver state is not DISPLAY_STATE_OPENED.
SSP_ERR_INVALID_CLUT_ACCESS	Illegal CLUT entry or size is specified.
p_version	The version number.

Note

Lower-level drivers may return common error codes. Refer to the SSP User's Manual API References for the associated module for a definition of all relevant status return values.

GLCDC HAL Module Operational Overview

The GLCDC HAL module controls an LCD panel. The following figure shows an overview of the graphics data flow using the GLCDC HAL module. The module supports reading graphics frame image data from memory (up to two frames) and blending those images on top of the monochrome background screen. The driver supports CLUT memory and specifies the graphic frame format for the CLUT.

GLCDC HAL Module Data Flow

The following figure shows a display system with a ping-pong frame buffer. It is recommended to have more than two frame buffers in a display system to avoid image tearing, which happens in a single frame buffer display system. In such designs, the GLCDC hardware can read a graphics frame image from one of the frame buffers while the image drawing engines (for example, DRW and JPEG), CPU or DMAC/DTC transfer a graphics frame image to another frame buffer simultaneously. The module supports frame buffer toggling by the display_api_t::layerChange API at run-time.

GLCDC HAL Module Ping-Pong Buffer System

Screen Format

The following figure shows the relationship between the LCD screen format and LCD timing parameters of the GLCDC module. The module has generic timing parameters for the LCD panel setting that support a variety of LCD panels.

GLCDC HAL Module Screen Format

Front Porch Period

The GLCDC module does not have a setting for horizontal/vertical front porch cycles/lines. Those cycles/lines must be included in the total horizontal cycles/vertical lines setting.

Note

The module requires setting the back porch cycles/lines based on the GLCDC hardware specification. Since typical LCD panels have a greater number of back porch cycles/lines than described, this is not a true limitation of the module.

• Number of the horizontal back porch cycles >= 3
• Number of the vertical back porch lines >= 2

Example Parameter Settings

PE-HMI1 v2.0 board (LXD Research & Display, LLC, M7504A):

The following example adjusts the horizontal total cycles, vertical total lines, and panel clock division ratio to generate an LCD panel refresh rate of 60 Hz. Regarding symbols for the LCD panel, see the M7504A data sheet.

LCD Panel Parameter Settings - PE-HMI1 v2.0 Board

DK-S7G2 v3.0 board (LXD Research & Display, LLC, M7190A):

The following example adjusts the horizontal total cycles, vertical total lines and panel clock division ration to generate an LCD panel refresh rate of 60 Hz. Regarding symbols for the LCD panel, see the M7190A data sheet.

LCD Panel Parameter Settings - DK-S7G2 v3.0 Board

SK-S7G2 v2.0 board (ILI Technology Corp., IL9341C):

The following example sets the horizontal total cycles, and vertical total lines as large as allowed for the panel for an LCD panel refresh rate of about 76.8 Hz. Regarding symbols for the LCD panel, see the LIL9314V data sheet.

LCD Panel Parameter Settings - SK-S7G2 v2.0 Board

Note

The input horizontal size and stride are intentionally set to 256 pixels, even though the parameter should be 240 pixels for the panel. This is because a horizontal line has to be 64-byte aligned for GLCDC hardware. Only 240 pixels from the beginning in a line are valid and rest of pixels in the line (16 pixels) are don't care.

CLUT

The GLCDC module supports a Color Look-Up Table that is used if the color format is ARGB1555, CLUT8, CLUT4, or CLUT1. The CLUT API can update CLUT0/CLUT1 SRAM (implemented inside the GLCDC hardware) for each of the graphics foreground or background screens.

Note

Make sure to call the CLUT API if you select a color format that uses the CLUT, before using the display_api_t::start API; otherwise, CLUT0 and CLUT1 become an unknown condition and the graphics do not display properly.

You can also call the CLUT API at run-time to update CLUT SRAM.

Note

The API copies the source of CLUT data to the CLUT SRAM, which is not currently used (each CLUT SRAM consists of a ping-pong buffer). After completing the CLUT data update, the API automatically switches the CLUT SRAM to be read by the GLCDC hardware from the next frame to avoid tearing of the image.

Line Repeating Mode

Line Repeating is an important mode, especially for a system that does not have enough of memory. In this mode, the GLCDC module reads a raster image, which has fewer pixels than the LCD panel screen size, and displays the raster repeatedly on the screen. The following figure shows an example of a screen image constructed by reading a small raster image repeatedly in the background graphics plane.

GLCDC HAL Module Line Repeating Mode

Note

To enable this mode, set the GLCDC module property "Input - Graphics screen N input lines repeat" (where N = 1 or 2) to ON with the Synergy configurator. Also, specify the repeat times to read a raster image to: "Input - Graphics screen N input lines repeat times". Specify the horizontal pixel size of the raster image in "Input - Graphics screen N input horizontal size" and "Input - Graphics screen N input horizontal stride," and then specify the vertical pixel size of the raster image in "Input - Graphics screen N input vertical size."

Gamma Correction

Gamma Correction is used to change the color characteristic of LCD panels to a flat characteristic. The following figure shows the gamma correction curve, which can be configured by the GLCDC module. The module supports 16 threshold values for the input color level for each (R, G, B) color and defines the gain level for each of 16 areas divided by thresholds.

GLCDC HAL Module Gamma Correction Curve

Note

To enable the gamma correction for each channel (R, G, B), set the GLCDC module property "Color correction – Gamma correction (R, G, B)" to ON using the Synergy configurator. Thresholds (total 16) are set to "Color correction – Gamma correction threshold (R, G, B) [n]," where n=[0..15]. The gain value for each of areas are set to "Color correction – Gamma correction gain (R, G, B) \[n]," where n= [0..15].

GLCDC HAL Module Important Operational Notes and Limitations

GLCDC HAL Module Operational Notes

You have the option to configure multiple GLCDC interrupts covered in the following sections:

Line Detection Interrupt

The line detection interrupt is used to indicate when the GLCDC finishes outputting all lines to the LCD panel and goes into the blanking period. Use this interrupt to handle frame buffer switching in a graphics system and uses frame buffers with more than two frames.

Layer1 or Layer2 Line Buffer Underflow Interrupt

You can use the GLCDC layer1 or layer2 buffer underflow interrupt to detect lack of memory bandwidth in your system. The buffer underflow occurs when the graphics data transfer from memory (for example, SDRAM or SRAM) to the GLCDC internal line buffer is blocked by the other data transfer, and not enough against the data transfer from GLCDC line buffer to the LCD panel interface. You have to design the graphics system to prevent this interrupt from occurring.

GLCDC Callbacks

A user callback function can be registered in open. If a user callback function is provided, the callback function is called from the interrupt service routine (ISR) each time an interrupt happens. The argument of the callback function event can take the following enumerated value listed the table, so that a user can identify which event occurred in the graphics system. DISPLAY_EVENT_LINE_DETECTION event is used for switching frame buffers to update the screen, and DISPLAY_EVENT_GRn_UNDERFLOW event is used for error handling if an underflow occurs.

Event and Interrupt Summary

Name of Event	Name of Interrupt	Condition for the Event
DISPLAY_EVENT_LINE_DETECTION	Line detection	When GLCDC is done outputting the last line in the active video region
DISPLAY_EVENT_GR1_UNDERFLOW	Graphics 1 underflow	When GLCDC underflows during reading the data for graphics1 plane
DISPLAY_EVENT_GR2_UNDERFLOW	Graphics 2 underflow	When GLCDC underflows during reading the data for graphics2 plane

Note

Since the callback is called from an ISR, be careful not to use blocking calls or lengthy processing. Spending an excessive time in an ISR can affect the responsiveness of the system.

GLCDC HAL Module Limitations

• The Display driver on r_glcd does not support RGB-index chroma key.
• The Display driver on r_glcd does not support the event link function.

Including the GLCDC HAL Module in an Application

This section describes how to include the GLCDC HAL Module in an application using the SSP configurator.

Note

This section assumes you are familiar with creating a project, adding threads, adding a stack to a thread and configuring a block within the stack. If you are unfamiliar with any of these items, refer to the first few chapters of the SSP User's Manual to learn how to manage each of these important steps in creating SSP-based applications.

To add the Display Driver to an application, simply add it to a thread using the stacks selection sequence given in the following table. (The default name for the Display Driver is g_display0. This name can be changed in the associated Properties window.)

GLCDC HAL Module Selection Sequence

Resource	ISDE Tab	Stacks Selection Sequence
g_display0 Display Driver on r_glcdc	Threads	New Stack> Driver> Graphics> Display Driver on r_glcdc

When the Display Driver on r_glcdc is added to the thread stack as shown in the following figure, the configurator automatically adds any needed lower‑level modules. Any modules needing additional configuration information have the box text highlighted in Red. Modules with a Gray band are individual modules that stand alone. Modules with a Blue band are shared or common; they need only be added once and can be used by multiple stacks. Modules with a Pink band can require the selection of lower-level modules; these are either optional or recommended. (This is indicated in the block with the inclusion of this text.) If the addition of lower-level modules is required, the module description include Add in the text. Clicking on any Pink banded modules brings up the New icon and displays possible choices.

GLCDC HAL Module Stack

Configuring the GLCDC HAL Module

The GLCDC HAL Module must be configured by the user for the desired operation. The available configuration settings and defaults for all the user-accessible properties are given in the properties tab within the SSP configurator and are shown in the following tables for easy reference. Only properties that can be changed without causing conflicts are available for modification. Other properties are locked and not available for changes and are identified with a lock icon for the locked property in the Properties window in the ISDE. This approach simplifies the configuration process and makes it much less error-prone than previous manual approaches to configuration. The available configuration settings and defaults for all the user-accessible properties are given in the Properties tab within the SSP Configurator and are shown in the following tables for easy reference.

Note

You may want to open your ISDE, create the module and explore the property settings in parallel with looking over the following configuration table settings. This will help orient you and can be a useful 'hands-on' approach to learning the ins and outs of developing with SSP.

Configuration Settings for the GLCDC HAL Module on r_glcdc

ISDE Property	Value	Description
Parameter Checking	BSP, Enabled, Disabled Default: BSP	Enable or disable the parameter checking.
Name	g_display0	The name to be used for a GLCDC module control block instance. This name is also used as the prefix of the other variable instances.
Name of display callback function to be defined by user	NULL	Name must be a valid C symbol.
Input - Panel clock source select	Internal clock (GLCDCLK), External clock (LCD_EXTCLK) Default: Internal clock (GLCDCLK)	Choose the panel clock source depends on your system.
Input - Graphics screen1	Used, Not used Default: Used	Specify "Used" if the graphics screen N is used. Then the frame buffer named "display_fb_background" for graphics screen1 and "display_fb_foreground" for graphics screen2 is auto-generated by ISDE. If not using either of the graphics screens, specify "Not used". Then the frame buffer is not created. Note that there is no memory read access to the frame buffer when you specify "Not used", which reduces the consumption of bus bandwidth.
Input - Graphics screen1 frame buffer name	fb_background	Custom name for frame buffer.
Input - Number of Graphics screen1 frame buffer	2	Number of graphics selection.
Input - section where Graphics screen1 frame buffer allocated	sdram	Specify the section name to allocate the frame buffer. This is valid if "Input - Graphics screen1" is set as "Used."
Input - Graphics screen1 input horizontal size	800	Specify the number of horizontal pixels. Default value is the size for an image with 800x480 pixels
Input - Graphics screen1 vertical size	480	Specify the number of vertical pixels. Default value is the size for an image with 800x480 pixels.
Input - Graphics screen1 input horizontal stride (not bytes but pixels)	800	Specify the memory stride for a horizontal line. This value must be specified with the number of pixels, not actual bytes. Typically, this parameter is set to same number as parameter 'input horizontal size'. Default value is the size for an image with 800x480 pixels.
Input - Graphics screen1 input format	32bits ARGB888, 32bits RGB888, 16bits RGB565, 16bits ARGB1555, 16bits ARGB4444, CLUT 8, CLUT 4, CLUT 1 Default: 16bits RGB565	Specify the graphics screen Input format. If selecting CLUT formats, you must write CLUT data using clut before performing start. Default setting supports a RGB565 formatted image.
Input - Graphics screen1 input line descending	Used, Not used Default: Not used	Specify "On" if image data descends from the bottom line to the top line in the frame buffer. Usually "Off".
Input - Graphics screen1 input line repeat	On, Off Default: Off	Specify "On" if expecting to repeatedly read a raster image which is smaller than the LCD panel size. Usually "Off". For details, see the description of Line Repeating function.
Input - Graphics screen1 input line repeat times	0	Specify the number of repeating times for a raster image which is read repeatedly in a frame.
Input - Graphics screen1 layer coordinate X	0	Specify the horizontal offset in pixels of the graphics screen from the background screen.
Input - Graphics screen1 layer coordinate Y	0	Specify the vertical offset in pixels of the graphics screen from the background screen.
Input - Graphics screen1 layer background color alpha	255	Based on the alpha value, either the graphics screen2 (foreground graphics screen) is blended into the graphics screen1 (background graphics screen) or the graphics screen1 is blended into the monochrome background screen.
Input - Graphics screen1 layer background color Red	255	Specify the background color in the graphics screen N.
Input - Graphics screen1 layer background color Green	255	Specify the background color in the graphics screen N.
Input - Graphics screen1 layer background color Blue	255	Specify the background color in the graphics screen N.
Input - Graphics screen1 layer fading control	None, Fade-in, Fade-out Default: None	Specify "On" when performing a fade-in for the graphics screen. The transparent screen changes gradually to opaque. Specify "Off" when performing the fade-out for the graphics screen. The opaque screen changes gradually to transparent. Note that this processing is accelerated by the GLCDC hardware and cannot stop once started. The transition status can be monitored by statusGet.
Input - Graphics screen1 layer fade speed	0	Specify the number of frames for the fading transition to complete.
Input - Graphics screen2	Used, Not used Default: Not used	Specify "Used" if the graphics screen N is used. Then the frame buffer named "display_fb_background" for graphics screen1 and "display_fb_foreground" for graphics screen2 is auto-generated by ISDE. If not using either of the graphics screens, specify "Not used". Then the frame buffer is not created. Note that there is no memory read access to the frame buffer when you specify "Not used", which reduces the consumption of bus bandwidth.
Input - Graphics screen2 frame buffer name	fb_foreground	Custom name for frame buffer.
Input - Number of Graphics screen2 frame buffer	2	Number of graphics selection.
Input - section where Graphics screen2 frame buffer allocated	sdram	Specify the section name to allocate the frame buffer. This is valid if "Input - Graphics screen1" is set as "Used."
Input - Graphics screen2 input horizontal size	800	Specify the number of horizontal pixels. Default value is the size for an image with 800x480 pixels
Input - Graphics screen2 vertical size	480	Specify the number of vertical pixels. Default value is the size for an image with 800x480 pixels.
Input - Graphics screen2 input horizontal stride (not bytes but pixels)	800	Specify the memory stride for a horizontal line. This value must be specified with the number of pixels, not actual bytes. Typically, this parameter is set to same number as parameter 'input horizontal size'. Default value is the size for an image with 800x480 pixels.
Input - Graphics screen2 input format	32bits ARGB888, 32bits RGB888, 16bits RGB565, 16bits ARGB1555, 16bits ARGB4444, CLUT 8, CLUT 4, CLUT 1 Default: 16bits RGB565	Specify the graphics screen Input format. If selecting CLUT formats, you must write CLUT data using clut before performing start. Default setting supports a RGB565 formatted image.
Input - Graphics screen2 input line descending	On, Off Default: Off	Specify "On" if image data descends from the bottom line to the top line in the frame buffer. Usually "Off".
Input - Graphics screen2 input line repeat	On, Off Default: Off	Specify "On" if expecting to repeatedly read a raster image which is smaller than the LCD panel size. Usually "Off". For details, see the description of Line Repeating function.
Input - Graphics screen2 input line repeat times	0	Specify the number of repeating times for a raster image which is read repeatedly in a frame.
Input - Graphics screen2 layer coordinate X	0	Specify the horizontal offset in pixels of the graphics screen from the background screen.
Input - Graphics screen2 layer coordinate Y	0	Specify the vertical offset in pixels of the graphics screen from the background screen.
Input - Graphics screen2 layer background color alpha	255	Based on the alpha value, either the graphics screen2 (foreground graphics screen) is blended into the graphics screen1 (background graphics screen) or the graphics screen1 is blended into the monochrome background screen.
Input - Graphics screen2 layer background color Red	255	Specify the background color in the graphics screen N.
Input - Graphics screen2 layer background color Green	255	Specify the background color in the graphics screen N.
Input - Graphics screen2 layer background color Blue	255	Specify the background color in the graphics screen N.
Input - Graphics screen2 layer fading control	None, Fade-in, Fade-out Default: None	Specify "On" when performing a fade-in for the graphics screen. The transparent screen changes gradually to opaque. Specify "Off" when performing the fade-out for the graphics screen. The opaque screen changes gradually to transparent. Note that this processing is accelerated by the GLCDC hardware and cannot stop once started. The transition status can be monitored by statusGet.
Input - Graphics screen2 layer fade speed	0	Specify the number of frames for the fading transition to complete.
Output - Horizontal total cycles	1024	Specify the total cycles in a horizontal line. Set to the number of cycles defined in the data sheet of LCD panel sheet in your system. Default value matches the LCD panel on S7G2 PE-HMI1 board.
Output - Horizontal active video cycles	800	Specify the number of active video cycles in a horizontal line. Set to the number of cycles defined in the data sheet of LCD panel sheet in your system. Default value matches the LCD panel on S7G2 PE-HMI1 board.
Output - Horizontal back porch cycles	46	Specify the number of back porch cycles in a horizontal line. Back porch starts from the beginning of Hsync cycles, which means back porch cycles contain Hsync cycles. Set to the number of cycles defined in the data sheet of LCD panel sheet in your system. Default value matches the LCD panel on S7G2 PE-HMI1 board.
Output - Horizontal sync signal cycles	20	Specify the number of Hsync signal assertion cycles. Set to the number of cycles defined in the data sheet of LCD panel sheet in your system. Default value matches LCD panel on S7G2 PE-HMI1 board.
Output - Horizontal sync signal polarity	Low active, High active Default: Low active	Select the polarity of Hsync signal to match your system. Default setting matches the LCD panel on S7G2 PE-HMI1 board.
Output - Vertical total lines	525	Specify number of total lines in a frame. Set to the number of lines defined in the data sheet of LCD panel sheet in your system. Default value matches the LCD panel on S7G2 PE-HMI1 board.
Output - Vertical active video lines	480	Specify the number of active video lines in a frame. Set to the number of lines defined in the data sheet of LCD panel sheet in your system. Default value matches the LCD panel on S7G2 PE-HMI1 board.
Output - Vertical back porch lines	23	Specify the number of back porch lines in a frame. Back porch starts from the beginning of Vsync lines, which means back porch lines contain Vsync lines. Set to the number of lines defined in the data sheet of LCD panel sheet in your system. Default value matches the LCD panel on S7G2 PE-HMI1 board.
Output - Vertical sync signal lines	10	Specify the Vsync signal assertion lines in a frame. Set to the number of lines defined in the data sheet of LCD panel sheet in your system. Default value matches the LCD panel on S7G2 PE-HMI1 board.
Output - Vertical sync signal polarity	Low active, High active Default: Low active	Select the polarity of Vsync signal to match to your system. Default setting matches LCD panel on S7G2 PE-HMI1 board.
Output - Format	24bits RGB888, 18bits RGB666, 16bits RGB565, 8bits serial Default: 24bits RGB888	Specify the graphics screen output format to match to your LCD panel. Default setting matches the LCD panel on S7G2 PE-HMI1 board.
Output - Endian	Little endian, Big endian Default: Little endian	Select data endian for output signal to LCD panel. Default setting matches the LCD panel on S7G2 PE-HMI1 board.
Output - Color order	RGB, BGR Default: RGB	Select data order for output signal to LCD panel. The order of blue and red can be swapped if needed. Default setting matches the LCD panel on S7G2 PE-HMI1 board.
Output - Data Enable Signal Polarity	Low active, High active Default: High active	Select the polarity of Data Enable signal to match to your system. Default setting matches the LCD panel on S7G2 PE-HMI1 board.
Output - Sync edge	Rising Edge, Falling Edge Default: Rising Edge	Select the polarity of Sync signals to match to your system. Default setting matches the LCD panel on S7G2 PE-HMI1 board.
Output - Background color alpha channel	255	Specify the background color of the background screens.
Output - Background color R channel	0	Specify the background color of the background screens.
Output - Background color G channel	0	Specify the background color of the background screens.
Output - Background color B channel	0	Specify the background color of the background screens.
CLUT	Used, Not used Default: Not used	Specify "Used" if selecting CLUT formats for a graphics screen input format. Then, a buffer named "CLUT_buffer" for the CLUT source data is generated in the ISDE auto-generated source file.
CLUT - CLUT buffer size	256	Specify the number of entries for the CLUT source data buffer. Each entries consumes 4 bytes (1 word). Words of CLUT source data specified by this parameter are generated in the ISDE auto-generated source file.
TCON - Hsync pin select	Not used, LCD_TCON0, LCD_TCON1, LCD_TCON2, LCD_TCON3 Default: LCD_TCON0	Select the TCON pin used for the Hsync signal to match to your system. Default setting is for LCD panel on S7G2 PE-HMI1 board.
TCON - Vsync pin select	Not used, LCD_TCON0, LCD_TCON1, LCD_TCON2, LCD_TCON3 Default: LCD_TCON1	Select TCON pin used for Vsync signal to match to your system. Default setting is for LCD panel on S7G2 PE-HMI1 board.
TCON - DataEnable pin select	Not used, LCD_TCON0, LCD_TCON1, LCD_TCON2, LCD_TCON3 Default: LCD_TCON2	Select TCON pin used for DataEnable signal to match to your system. Default setting is for LCD panel on S7G2 PE-HMI1 board.
TCON - Panel clock division ratio	1/1, 1/2, 1/3, 1/4, 1/5, 1/6, 1/7, 1/8, 1/9, 1/12, 1/16, 1/24, 1/32 Default: 1/8	Select the clock source divider value. See the note at bottom of this table about the source clock for the pixel clock.
Color correction - Brightness	Off, On Default: Off	Specify "On" when performing brightness control. If specifying "Off", the setting below does not affect the output color.
Color correction - Brightness R channel	512	Output color level is calculated as follows: Output color level = Input color level +/ - 512. Set the value for each of R, G, B channels.
Color correction - Brightness G channel	512	Output color level is calculated as follows: Output color level = Input color level +/ - 512. Set the value for each of R, G, B channels.
Color correction - Brightness B channel	512	Output color level is calculated as follows: Output color level = Input color level +/ - 512. Set the value for each of R, G, B channels.
Color correction - Contrast	Off, On Default: Off	Specify "On" when performing contrast control. If specifying "Off", the setting below does not affect the output color.
Color correction - Contrast(gain) R channel	128	Output color level is calculated as follows: Output color level = Input color level x (/128). Set the value for each of R, G, B channels.
Color correction - Contrast(gain) G channel	128	Output color level is calculated as follows: Output color level = Input color level x (/128). Set the value for each of R, G, B channels.
Color correction - Contrast(gain) B channel	128	Output color level is calculated as follows: Output color level = Input color level x (/128). Set the value for each of R, G, B channels.
Color correction - Gamma correction(Red)	Off, On Default: Off	Control for each channel R/G/B. Specify "On" when performing gamma correction for the red channel. If specifying "Off", the settings for gain and threshold do not affect the output color.
Color correction - Gamma gain R[0-15]	0	Set the gain value for the red channel in the area N on the gamma correction curve. The gain setting for area N is applied to the input data with a color level between ((Gamma threshold R[N-1])<<2) and ((Gamma threshold R[N])<<2). The output value is calculated as follows: Output color level = Input color level / 1024 (/128).
Color correction - Gamma threshold R[0-15]	0	Set the threshold value for the red channel in the area N on the gamma correction curve. The gain setting for area N is applied to the input data with a color level between Gamma threshold R[N-1] and Gamma threshold R[N]. The output value is calculated as follows: Output color level = Input color level / 1024 (/128).
Color correction - Gamma correction(Green)	Off, On Default: Off	Control for each channel R/G/B. Specify "On" when performing gamma correction for the red channel. If specifying "Off", the settings for gain and threshold do not affect the output color.
Color correction - Gamma gain G[0-15]	0	Set the gain value for the red channel in the area N on the gamma correction curve. The gain setting for area N is applied to the input data with a color level between ((Gamma threshold R[N-1])<<2) and ((Gamma threshold R[N])<<2). The output value is calculated as follows: Output color level = Input color level / 1024 (/128).
Color correction - Gamma threshold G[0-15]	0	Set the threshold value for the red channel in the area N on the gamma correction curve. The gain setting for area N is applied to the input data with a color level between Gamma threshold R[N-1] and Gamma threshold R[N]. The output value is calculated as follows: Output color level = Input color level / 1024 (/128).
Color correction - Gamma correction(Blue)	Off, On Default: Off	Control for each channel R/G/B. Specify "On" when performing gamma correction for the red channel. If specifying "Off", the settings for gain and threshold do not affect the output color.
Color correction - Gamma gain B[0-15]	0	Set the gain value for the red channel in the area N on the gamma correction curve. The gain setting for area N is applied to the input data with a color level between ((Gamma threshold R[N-1])<<2) and ((Gamma threshold R[N])<<2). The output value is calculated as follows: Output color level = Input color level / 1024 (/128).
Color correction - Gamma threshold B[0-15]	0	Set the threshold value for the red channel in the area N on the gamma correction curve. The gain setting for area N is applied to the input data with a color level between Gamma threshold R[N-1] and Gamma threshold R[N]. The output value is calculated as follows: Output color level = Input color level / 1024 (/128).
Dithering	Off, On Default: Off	Dithering enable. Specify "On" when applying the dither effect to reduce the banding in case of selecting RGB666 or RGB565 output formats. Dithering can be applied when converting. If specified "Off", the settings for dithering below do not affect the output. For details on the dither effect, see Output Control Block Panel Dither Correction Register (OUT_PDTHA) in the hardware manual.
Dithering - Mode	Truncate, Round off, 2x2 Pattern Default: Truncate	Specify the dither mode. For detail, see the Output Control Block Panel Dither Correction Register (OUT_PDTHA) in the hardware manual.
Dithering - Pattern A	Pattern 00, Pattern 01, Pattern 10, Pattern 11 Default: Pattern 11	Specify the dither pattern for 2X2 pattern mode. For details, see the Output Control Block Panel Dither Correction Register (OUT_PDTHA) in the hardware manual.
Dithering - Pattern B	Pattern 00, Pattern 01, Pattern 10, Pattern 11 Default: Pattern 11	Specify the dither pattern for 2X2 pattern mode. For details, see the Output Control Block Panel Dither Correction Register (OUT_PDTHA) in the hardware manual.
Dithering - Pattern C	Pattern 00, Pattern 01, Pattern 10, Pattern 11 Default: Pattern 11	Specify the dither pattern for 2X2 pattern mode. For details, see the Output Control Block Panel Dither Correction Register (OUT_PDTHA) in the hardware manual.
Dithering - Pattern D	Pattern 00, Pattern 01, Pattern 10, Pattern 11 Default: Pattern 11	Specify the dither pattern for 2X2 pattern mode. For details, see the Output Control Block Panel Dither Correction Register (OUT_PDTHA) in the hardware manual.
Misc - Correction Process Order	Brightness and Contrast then Gamma, Gamma then Brightness and Contrast Default: Brightness and Contrast then Gamma	Specify the color correction processing order if needed.
Line Detect Interrupt Priority	Priority 0 (highest), Priority 1:14 Priority 15 (lowest - not valid if using ThreadX), Default: Disabled	The driver needs valid interrupt priority setting and it will not work if disabled.
Underflow 1 Interrupt Priority	Priority 0 (highest), Priority 1:14 Priority 15 (lowest - not valid if using ThreadX), Default: Disabled	The driver needs valid interrupt priority setting and it will not work if disabled.
Underflow 2 Interrupt Priority	Priority 0 (highest), Priority 1:14 Priority 15 (lowest - not valid if using ThreadX), Default: Disabled	The driver needs valid interrupt priority setting and it will not work if disabled.

Note

The example settings and defaults are for a project using the Synergy S7G2 MCU Group. Other MCUs may have different default values and available configuration settings.

GLCDC HAL Module Clock Configuration

The GLCDC module can generate the pixel clock from either of the following clock sources (the source clock selection is available through Synergy Configuration in e² studio):

• Internal clock source (PLLOUT; 240 MHz)
• External clock source from the LCD_EXTCLK pin

Note

The internal clock is different in the S7G2 WS1 (Working Sample1) chip and the WS2 (Working Sample2) chip or later. The WS1 chip uses the PCLKB (max. 60 MHz), but WS2 or later chips use the PLLOUT (max. 240 MHz).

GLCDC HAL Module Pin Configuration

The GLCDC module uses pins on the MCU to communicate to external devices. I/O pins must be selected and configured as required by the external device.  The pin selection table lists methods to select pins within the SSP configuration window and the configuration settings table lists an example depicting selection of GLCDC pins:

Pin Selection for the GLCDC HAL Module on r_glcdc

Resource	ISDE Tab	Pin selection Sequence
GLCDC	Pins	Select Peripherals> Graphics: GLCDC> GLCDC0

Note

The selection sequence assumes GLCDC0 is the desired hardware target for the driver.

Pin Configuration Settings for GLCDC HAL Module on r_glcd

Property	Value	Description
Pin Group Selection	Mixed, _A Only, _B Only Default: Mixed	Pin group selection.
Operation Mode	Disabled, Custom, RGB888, RGB666, RGB565 Default: Disabled	Select desired operation mode.
LCD_CLK	None, P900, P101 Default: None	LCD_CLK Pin.
LCD_DATA00:15	None, Pn, Pm Default: None	LCD_DATA Pins.
LCD_TCON0:3	None, Pn, Pm Default: None	LCD_TCON Pins.
LCD_EXTCLK	None, Pn, Pm Default: None	LCD_EXTCLK Pin.

Note

The example settings are for a project using the Synergy S7G2 MCU Group and the SK-S7G2 Kit. Other Synergy MCUs and Synergy Kits may have different available pin configuration settings.

To use the GLCDC module on the S7G2 PE-HMI1 board, be sure to set up PORT10 pin3 (PA03) and pin5 (PA05) as IOPORT pins with the output level HIGH. Pin PA03 controls the DISP signal (Display on/off) and Pin PA05 controls the backlight of LCD panel. For details, see the schematics of S7G2 PE-HMI1 board.

Using the GLCDC HAL Module in an Application

• The typical steps in using the GLCDC HAL module in an application are:

1. Initialize the GLCDC HAL module with the display_api_t::open API.
2. Draw a primary image in the frame buffer with application code.
3. Start the image displaying using the display_api_t::start API.
4. Stop the image displaying using the display_api_t::stop API.
5. Copy the source CLUT data to CLUT SRAM using the display_api_t::clut API.
6. Draw a new image in the frame buffer to update the display with application code.

   • Note

     In a typical application a ping-pong frame buffer system is used, so the application will draw the image to another frame buffer, which is not used for displaying at this point.

7. Request frame buffer toggling to the GLCDC hardware with the display_api_t::layerChange API.

   • Note

     The GLCDC hardware toggles the frame buffer and displays a new image from the next frame.

8. Perform color correction using the display_api_t::correction API.
9. Get display status using the display_api_t::statusGet API.
10. Get the driver version using display_api_t::versionGet API. (Optional)
11. Close the GLCDC module by calling the display_api_t::close API.

To synchronize application code to the completion of drawing current frame buffer, use the Line Detection Interrupt and notify the timing to application code through the GLCDC callback.

These common steps are illustrated in a typical operational flow diagram in the following figure:

Flow Diagram of a Typical GLCDC HAL Module Application