David Smart / RA8875 Featured

Library to control a Graphics TFT connected to 4-wire SPI - revised for the Raio RA8875 Display Controller.

Dependents:   FRDM_RA8875_mPaint RA8875_Demo RA8875_KeyPadDemo SignalGenerator ... more

Fork of SPI_TFT by Peter Drescher

See Components - RA8875 Based Display

Enhanced touch-screen support - where it previous supported both the Resistive Touch and Capacitive Touch based on the FT5206 Touch Controller, now it also has support for the GSL1680 Touch Controller.

Offline Help Manual (Windows chm)

/media/uploads/WiredHome/ra8875.zip.bin (download, rename to .zip and unzip)

Files at this revision

API Documentation at this revision

Revision 34:c99ec28fac66, committed 2014-01-23

Comitter:
WiredHome
Date:
Thu Jan 23 23:45:20 2014 +0000
Parent:
33:b6b710758ab3
Child:
35:7dcab9e3ab25
Commit message:
Updated documentation for the RenderBitmapFile function.

Changed in this revision

GraphicsDisplay.cpp Show annotated file Show diff for this revision Revisions of this file
GraphicsDisplay.h Show annotated file Show diff for this revision Revisions of this file 
--- a/GraphicsDisplay.cpp	Wed Jan 22 03:50:55 2014 +0000
+++ b/GraphicsDisplay.cpp	Thu Jan 23 23:45:20 2014 +0000
@@ -2,10 +2,7 @@
  * Copyright (c) 2007-2009 sford
  * Released under the MIT License: http://mbed.org/license/mit
  *
- * Software Rendering of a Bitmap from the localfilesystem
- *      34 sec: 352x272 pixels, 8-bit color, 94.5kbytes
- * Hardware Rendering
- *       9 sec: same file.
+ * Derivative work by D.Smart 2014
  */
 
 #include "GraphicsDisplay.h"

--- a/GraphicsDisplay.h	Wed Jan 22 03:50:55 2014 +0000
+++ b/GraphicsDisplay.h	Thu Jan 23 23:45:20 2014 +0000
@@ -173,6 +173,24 @@
     ///         from the top down; as a result, it constantly 'seeks'
     ///         on the file system for the next row of information.
     ///
+    /// As a performance test, a sample picture was timed. A family picture
+    /// was converted to Bitmap format; shrunk to 352 x 272 pixels and save
+    /// in 8-bit color format. The resulting file size was 94.5 KByte.
+    /// The SPI port interface was set to 20 MHz.
+    /// The original bitmap rendering software was purely in software, 
+    /// pushing 1 pixel at a time to the write function, which did use SPI
+    /// hardware (not pin wiggling) to transfer commands and data to the 
+    /// display. Then, the driver was improved to leverage the capability
+    /// of the derived display driver. As a final check, instead of the
+    /// [known slow] local file system, a randomly chosen USB stick was 
+    /// used. The performance results are impressive (but depend on the
+    /// listed factors). 
+    ///
+    /// File System     | Rendering Method | Rendering Time
+    /// LocalFileSystem | Software only    | 34 sec
+    /// LocalFileSystem | Hardware RA8875  | 9 sec
+    /// MSCFileSystem   | Hardware RA8875  | 3 sec
+    /// 
     /// @param x is the horizontal pixel coordinate
     /// @param y is the vertical pixel coordinate
     /// @param Name_BMP is the filename on the local file system.