st7735s: documentation, ready for merge

diff --git a/README.md b/README.md
index d891e3c..1463117 100644 (file)
--- a/README.md
+++ b/README.md
@@ -29,7 +29,7 @@ port this code to any Cortex M0/M3/M4/M7 board.
        * Temperature sensor: drivers/tsensor.c [COMPLETED]
        * OLED display [PLANNED]
        * Joystick: drivers/mk450_joystick.c [COMPLETED]
-       * TFT Screen: [PLANNED] 
+       * TFT Screen: drivers/st7735s.c, include/libs/fonts/wogfont.h [IN PROGRESS]
 * Memory Management [IN PROGRESS] -- FILE: lib/pool.c
 * User Mode [PLANNED]
 * System Call PendV implementation [PLANNED]
@@ -39,9 +39,13 @@ port this code to any Cortex M0/M3/M4/M7 board.
 * Multiple processes and scheduling [PLANNED]
 
 ## SCREENSHOTS
-Here is a screenshot that shows the terminal just after booting:
+Here are some screenshots that shows the terminal just after booting:
 
-![Screenshot](https://github.com/robinkrens/cortex-from-scratch/raw/master/img/screenshot.png "screenshot")
+* Serial (over UART)
+![Screenshot](https://github.com/robinkrens/cortex-from-scratch/raw/master/img/serial.png "serial terminal screenshot")
+
+* TFT screen output (SPI):
+![Screenshot](https://github.com/robinkrens/cortex-from-scratch/raw/master/img/tft.png "tft peripheral screenshot")
 
 
 

diff --git a/drivers/st7735s.c b/drivers/st7735s.c
index c99156f..a3c7117 100644 (file)
--- a/drivers/st7735s.c
+++ b/drivers/st7735s.c
@@ -5,8 +5,19 @@
  * Initial version 
  * 
  * $DESCRIPTION$
+ * Basic driver for the ST7735s TFT screen. Initializes the screen 
+ * Low-level commands can be called by tft_command. See header (.h)
+ * file for an overview of all commands. tft_command can accepts
+ * an unlimited amount of data or parameter commands.
  * 
  * $USAGE$
+ * I added the following functionality:
+ * a. tft_fill: fills a certain area of the screen
+ * b. tft_setpixel: sets a single pixel
+ * c. tft_putc, tft_put: outputs a char/string to the screen, starts
+ * at the upper top right and tracks the position. If the screen is
+ * full, it 'scrolls' automatically. So you basically have a mini 
+ * sized terminal. You can link standard output to this function!
  *
  * */
 
@@ -35,6 +46,7 @@
 #define YPOS(y) (y * 8)
 #define BUFFER 352
 
+
 static struct {
         uint16_t cpos;
         uint8_t * textmemptr;
@@ -188,6 +200,7 @@ tft_command(TFT_RAMWR, 2, (uint8_t) (color >> 8), (uint8_t) (color & 0xFF));
 }
 
 
+/* Basic puts function that loops over a string */
 int tft_puts(char * str) {
 
        for (int i = 0; i < strlen(str); i++)  {
@@ -197,6 +210,8 @@ int tft_puts(char * str) {
        
 }
 
+/* Used by scroll function to overwrite and clear the last
+ * line on the screen */
 void tft_clrln() {
 
        tft_puts("                     ");
@@ -211,26 +226,20 @@ int tft_scroll() {
 
        /* Scroll the buffer  */
        memcpy(tftscreen.textmemptr, tftscreen.textmemptr + 21, BUFFER - 21);
-       //for (int i = 21; i >= 0; i--)
        tftscreen.buf[BUFFER - 21] = '\0';
 
        tftscreen.x = 0;
        tftscreen.y = 0;
        tftscreen.cpos = 0;
 
-       //for (int i = 0; i < 320; i++)     {
-       //      uart_putc(tftscreen.buf[i]);
-       //}
-
        tft_puts(tftscreen.buf); // CHECK: ending
-       //tftscreen.y = 14;
-       //tft_puts("                     ");
        tftscreen.y = 14;
        tftscreen.x = 0;
        tftscreen.cpos = BUFFER - 21;
-       // DINOSAUR tft_clrln();
 }
 
+/* Fills a line with blank characters, returns to 
+ * the next line */
 void tft_nl() {
 
        uint8_t blanks = 21 - tftscreen.x;
@@ -246,19 +255,11 @@ void tft_nl() {
  * Should not be used directly */
 int tft_putc(uint16_t fg, uint16_t bg, int c) {
 
-       
        int totalpixels = 35;
        int column = 0;
        int row = 0;
        uint8_t current;
 
-
-       //if ((c == '\n') && (tftscreen.y == 14)) {
-       //      tft_nl();
-       //      tft_scroll2();
-       //      return 1;
-       //}
-
        if (c == '\n') {
                if (tftscreen.y == 14) {
                        tft_nl();
@@ -270,20 +271,9 @@ int tft_putc(uint16_t fg, uint16_t bg, int c) {
                        return 1;
                }
        }
-       ////    else {
-       ////            tft_putc(0xFFFF, 0x0000, 'o');
-       ////    }
-       //      //else {
-       //      //      ENDFLAG = true;
-       //      //}
-       //}
 
        if (tftscreen.y >= 15) {
                tft_scroll();
-               //if (ENDFLAG) {
-               //      ENDFLAG = false;
-               //      return 1;
-               //}
        }
 
        tft_command(TFT_CASET, 4, 0x00, STARTX + XPOS(tftscreen.x), 0x00, (STARTX + 4) + XPOS(tftscreen.x));

diff --git a/img/screenshot.png b/img/screenshot.png
deleted file mode 100644 (file)
index d2823f7..0000000
Binary files a/img/screenshot.png and /dev/null differ

diff --git a/img/serial.png b/img/serial.png
new file mode 100644 (file)
index 0000000..d2823f7
Binary files /dev/null and b/img/serial.png differ

diff --git a/img/tft.png b/img/tft.png
new file mode 100644 (file)
index 0000000..cb83eea
Binary files /dev/null and b/img/tft.png differ

diff --git a/include/lib/fonts/wogfont.h b/include/lib/fonts/wogfont.h
index 28cb942..45f13c8 100644 (file)
--- a/include/lib/fonts/wogfont.h
+++ b/include/lib/fonts/wogfont.h
@@ -5,9 +5,30 @@
  * Initial version 
  * 
  * $DESCRIPTION$
- * The classic wogfont is back!
- * Designed by Robin Krens
- * 5 by 7 bit font (lower case) 
+ * A non-standard 5 by 7 bit font (ALL CHARs ARE UPPER CASE)
+ * Some characters I haven't designed yet, these will display
+ * a'█' on a VGA or TFT screen. A character is column hex-coded. 
+ *
+ * An example to make things clear!
+ * The letter 'S's bitmap is: 
+ *
+ * WIDTH = 5
+ * ##### L
+ * #___# E
+ * #____ N
+ * ##### G
+ * ____# T
+ * #___# H
+ * ##### = 7
+ *
+ * # represents a selected bit, 1
+ * _ represents a non selected bit, 0
+ *  
+ * For example, the first column is 1111101, the second columm 1001001
+ * For hex encoding we start at the MSB, the first LSB is never used
+ * The first column is 0xF6 and the second column 0x92. The letter 'S' 
+ * equals to: 0xF6, 0x92, 0x92, 0x92, 0xDE, 
+ *
  * */
 
 const uint8_t ASCII5x7[] = {