From 9df7862e97bde5af89fc307516adf5784a1a7c9c Mon Sep 17 00:00:00 2001
From: Dejvino <dejvino@gmail.com>
Date: Sat, 1 Aug 2020 19:49:42 +0000
Subject: [PATCH] Initial working version

---
 font8x8_basic.h | 152 ++++++++++++++++++++++
 main.c          |  75 +++++++++++
 meson.build     |   3 +
 st7735.c        | 332 ++++++++++++++++++++++++++++++++++++++++++++++++
 st7735.h        | 100 +++++++++++++++
 5 files changed, 662 insertions(+)
 create mode 100644 font8x8_basic.h
 create mode 100644 main.c
 create mode 100644 meson.build
 create mode 100644 st7735.c
 create mode 100644 st7735.h

diff --git a/font8x8_basic.h b/font8x8_basic.h
new file mode 100644
index 0000000..125cf16
--- /dev/null
+++ b/font8x8_basic.h
@@ -0,0 +1,152 @@
+/**
+ * 8x8 monochrome bitmap fonts for rendering
+ * Author: Daniel Hepper <daniel@hepper.net>
+ *
+ * License: Public Domain
+ *
+ * Based on:
+ * // Summary: font8x8.h
+ * // 8x8 monochrome bitmap fonts for rendering
+ * //
+ * // Author:
+ * //     Marcel Sondaar
+ * //     International Business Machines (public domain VGA fonts)
+ * //
+ * // License:
+ * //     Public Domain
+ *
+ * Fetched from: http://dimensionalrift.homelinux.net/combuster/mos3/?p=viewsource&file=/modules/gfx/font8_8.asm
+ **/
+
+// Constant: font8x8_basic
+// Contains an 8x8 font map for unicode points U+0000 - U+007F (basic latin)
+char font8x8_basic[128][8] = {
+    { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},   // U+0000 (nul)
+    { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},   // U+0001
+    { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},   // U+0002
+    { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},   // U+0003
+    { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},   // U+0004
+    { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},   // U+0005
+    { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},   // U+0006
+    { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},   // U+0007
+    { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},   // U+0008
+    { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},   // U+0009
+    { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},   // U+000A
+    { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},   // U+000B
+    { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},   // U+000C
+    { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},   // U+000D
+    { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},   // U+000E
+    { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},   // U+000F
+    { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},   // U+0010
+    { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},   // U+0011
+    { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},   // U+0012
+    { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},   // U+0013
+    { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},   // U+0014
+    { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},   // U+0015
+    { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},   // U+0016
+    { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},   // U+0017
+    { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},   // U+0018
+    { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},   // U+0019
+    { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},   // U+001A
+    { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},   // U+001B
+    { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},   // U+001C
+    { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},   // U+001D
+    { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},   // U+001E
+    { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},   // U+001F
+    { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},   // U+0020 (space)
+    { 0x18, 0x3C, 0x3C, 0x18, 0x18, 0x00, 0x18, 0x00},   // U+0021 (!)
+    { 0x36, 0x36, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},   // U+0022 (")
+    { 0x36, 0x36, 0x7F, 0x36, 0x7F, 0x36, 0x36, 0x00},   // U+0023 (#)
+    { 0x0C, 0x3E, 0x03, 0x1E, 0x30, 0x1F, 0x0C, 0x00},   // U+0024 ($)
+    { 0x00, 0x63, 0x33, 0x18, 0x0C, 0x66, 0x63, 0x00},   // U+0025 (%)
+    { 0x1C, 0x36, 0x1C, 0x6E, 0x3B, 0x33, 0x6E, 0x00},   // U+0026 (&)
+    { 0x06, 0x06, 0x03, 0x00, 0x00, 0x00, 0x00, 0x00},   // U+0027 (')
+    { 0x18, 0x0C, 0x06, 0x06, 0x06, 0x0C, 0x18, 0x00},   // U+0028 (()
+    { 0x06, 0x0C, 0x18, 0x18, 0x18, 0x0C, 0x06, 0x00},   // U+0029 ())
+    { 0x00, 0x66, 0x3C, 0xFF, 0x3C, 0x66, 0x00, 0x00},   // U+002A (*)
+    { 0x00, 0x0C, 0x0C, 0x3F, 0x0C, 0x0C, 0x00, 0x00},   // U+002B (+)
+    { 0x00, 0x00, 0x00, 0x00, 0x00, 0x0C, 0x0C, 0x06},   // U+002C (,)
+    { 0x00, 0x00, 0x00, 0x3F, 0x00, 0x00, 0x00, 0x00},   // U+002D (-)
+    { 0x00, 0x00, 0x00, 0x00, 0x00, 0x0C, 0x0C, 0x00},   // U+002E (.)
+    { 0x60, 0x30, 0x18, 0x0C, 0x06, 0x03, 0x01, 0x00},   // U+002F (/)
+    { 0x3E, 0x63, 0x73, 0x7B, 0x6F, 0x67, 0x3E, 0x00},   // U+0030 (0)
+    { 0x0C, 0x0E, 0x0C, 0x0C, 0x0C, 0x0C, 0x3F, 0x00},   // U+0031 (1)
+    { 0x1E, 0x33, 0x30, 0x1C, 0x06, 0x33, 0x3F, 0x00},   // U+0032 (2)
+    { 0x1E, 0x33, 0x30, 0x1C, 0x30, 0x33, 0x1E, 0x00},   // U+0033 (3)
+    { 0x38, 0x3C, 0x36, 0x33, 0x7F, 0x30, 0x78, 0x00},   // U+0034 (4)
+    { 0x3F, 0x03, 0x1F, 0x30, 0x30, 0x33, 0x1E, 0x00},   // U+0035 (5)
+    { 0x1C, 0x06, 0x03, 0x1F, 0x33, 0x33, 0x1E, 0x00},   // U+0036 (6)
+    { 0x3F, 0x33, 0x30, 0x18, 0x0C, 0x0C, 0x0C, 0x00},   // U+0037 (7)
+    { 0x1E, 0x33, 0x33, 0x1E, 0x33, 0x33, 0x1E, 0x00},   // U+0038 (8)
+    { 0x1E, 0x33, 0x33, 0x3E, 0x30, 0x18, 0x0E, 0x00},   // U+0039 (9)
+    { 0x00, 0x0C, 0x0C, 0x00, 0x00, 0x0C, 0x0C, 0x00},   // U+003A (:)
+    { 0x00, 0x0C, 0x0C, 0x00, 0x00, 0x0C, 0x0C, 0x06},   // U+003B (;)
+    { 0x18, 0x0C, 0x06, 0x03, 0x06, 0x0C, 0x18, 0x00},   // U+003C (<)
+    { 0x00, 0x00, 0x3F, 0x00, 0x00, 0x3F, 0x00, 0x00},   // U+003D (=)
+    { 0x06, 0x0C, 0x18, 0x30, 0x18, 0x0C, 0x06, 0x00},   // U+003E (>)
+    { 0x1E, 0x33, 0x30, 0x18, 0x0C, 0x00, 0x0C, 0x00},   // U+003F (?)
+    { 0x3E, 0x63, 0x7B, 0x7B, 0x7B, 0x03, 0x1E, 0x00},   // U+0040 (@)
+    { 0x0C, 0x1E, 0x33, 0x33, 0x3F, 0x33, 0x33, 0x00},   // U+0041 (A)
+    { 0x3F, 0x66, 0x66, 0x3E, 0x66, 0x66, 0x3F, 0x00},   // U+0042 (B)
+    { 0x3C, 0x66, 0x03, 0x03, 0x03, 0x66, 0x3C, 0x00},   // U+0043 (C)
+    { 0x1F, 0x36, 0x66, 0x66, 0x66, 0x36, 0x1F, 0x00},   // U+0044 (D)
+    { 0x7F, 0x46, 0x16, 0x1E, 0x16, 0x46, 0x7F, 0x00},   // U+0045 (E)
+    { 0x7F, 0x46, 0x16, 0x1E, 0x16, 0x06, 0x0F, 0x00},   // U+0046 (F)
+    { 0x3C, 0x66, 0x03, 0x03, 0x73, 0x66, 0x7C, 0x00},   // U+0047 (G)
+    { 0x33, 0x33, 0x33, 0x3F, 0x33, 0x33, 0x33, 0x00},   // U+0048 (H)
+    { 0x1E, 0x0C, 0x0C, 0x0C, 0x0C, 0x0C, 0x1E, 0x00},   // U+0049 (I)
+    { 0x78, 0x30, 0x30, 0x30, 0x33, 0x33, 0x1E, 0x00},   // U+004A (J)
+    { 0x67, 0x66, 0x36, 0x1E, 0x36, 0x66, 0x67, 0x00},   // U+004B (K)
+    { 0x0F, 0x06, 0x06, 0x06, 0x46, 0x66, 0x7F, 0x00},   // U+004C (L)
+    { 0x63, 0x77, 0x7F, 0x7F, 0x6B, 0x63, 0x63, 0x00},   // U+004D (M)
+    { 0x63, 0x67, 0x6F, 0x7B, 0x73, 0x63, 0x63, 0x00},   // U+004E (N)
+    { 0x1C, 0x36, 0x63, 0x63, 0x63, 0x36, 0x1C, 0x00},   // U+004F (O)
+    { 0x3F, 0x66, 0x66, 0x3E, 0x06, 0x06, 0x0F, 0x00},   // U+0050 (P)
+    { 0x1E, 0x33, 0x33, 0x33, 0x3B, 0x1E, 0x38, 0x00},   // U+0051 (Q)
+    { 0x3F, 0x66, 0x66, 0x3E, 0x36, 0x66, 0x67, 0x00},   // U+0052 (R)
+    { 0x1E, 0x33, 0x07, 0x0E, 0x38, 0x33, 0x1E, 0x00},   // U+0053 (S)
+    { 0x3F, 0x2D, 0x0C, 0x0C, 0x0C, 0x0C, 0x1E, 0x00},   // U+0054 (T)
+    { 0x33, 0x33, 0x33, 0x33, 0x33, 0x33, 0x3F, 0x00},   // U+0055 (U)
+    { 0x33, 0x33, 0x33, 0x33, 0x33, 0x1E, 0x0C, 0x00},   // U+0056 (V)
+    { 0x63, 0x63, 0x63, 0x6B, 0x7F, 0x77, 0x63, 0x00},   // U+0057 (W)
+    { 0x63, 0x63, 0x36, 0x1C, 0x1C, 0x36, 0x63, 0x00},   // U+0058 (X)
+    { 0x33, 0x33, 0x33, 0x1E, 0x0C, 0x0C, 0x1E, 0x00},   // U+0059 (Y)
+    { 0x7F, 0x63, 0x31, 0x18, 0x4C, 0x66, 0x7F, 0x00},   // U+005A (Z)
+    { 0x1E, 0x06, 0x06, 0x06, 0x06, 0x06, 0x1E, 0x00},   // U+005B ([)
+    { 0x03, 0x06, 0x0C, 0x18, 0x30, 0x60, 0x40, 0x00},   // U+005C (\)
+    { 0x1E, 0x18, 0x18, 0x18, 0x18, 0x18, 0x1E, 0x00},   // U+005D (])
+    { 0x08, 0x1C, 0x36, 0x63, 0x00, 0x00, 0x00, 0x00},   // U+005E (^)
+    { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xFF},   // U+005F (_)
+    { 0x0C, 0x0C, 0x18, 0x00, 0x00, 0x00, 0x00, 0x00},   // U+0060 (`)
+    { 0x00, 0x00, 0x1E, 0x30, 0x3E, 0x33, 0x6E, 0x00},   // U+0061 (a)
+    { 0x07, 0x06, 0x06, 0x3E, 0x66, 0x66, 0x3B, 0x00},   // U+0062 (b)
+    { 0x00, 0x00, 0x1E, 0x33, 0x03, 0x33, 0x1E, 0x00},   // U+0063 (c)
+    { 0x38, 0x30, 0x30, 0x3e, 0x33, 0x33, 0x6E, 0x00},   // U+0064 (d)
+    { 0x00, 0x00, 0x1E, 0x33, 0x3f, 0x03, 0x1E, 0x00},   // U+0065 (e)
+    { 0x1C, 0x36, 0x06, 0x0f, 0x06, 0x06, 0x0F, 0x00},   // U+0066 (f)
+    { 0x00, 0x00, 0x6E, 0x33, 0x33, 0x3E, 0x30, 0x1F},   // U+0067 (g)
+    { 0x07, 0x06, 0x36, 0x6E, 0x66, 0x66, 0x67, 0x00},   // U+0068 (h)
+    { 0x0C, 0x00, 0x0E, 0x0C, 0x0C, 0x0C, 0x1E, 0x00},   // U+0069 (i)
+    { 0x30, 0x00, 0x30, 0x30, 0x30, 0x33, 0x33, 0x1E},   // U+006A (j)
+    { 0x07, 0x06, 0x66, 0x36, 0x1E, 0x36, 0x67, 0x00},   // U+006B (k)
+    { 0x0E, 0x0C, 0x0C, 0x0C, 0x0C, 0x0C, 0x1E, 0x00},   // U+006C (l)
+    { 0x00, 0x00, 0x33, 0x7F, 0x7F, 0x6B, 0x63, 0x00},   // U+006D (m)
+    { 0x00, 0x00, 0x1F, 0x33, 0x33, 0x33, 0x33, 0x00},   // U+006E (n)
+    { 0x00, 0x00, 0x1E, 0x33, 0x33, 0x33, 0x1E, 0x00},   // U+006F (o)
+    { 0x00, 0x00, 0x3B, 0x66, 0x66, 0x3E, 0x06, 0x0F},   // U+0070 (p)
+    { 0x00, 0x00, 0x6E, 0x33, 0x33, 0x3E, 0x30, 0x78},   // U+0071 (q)
+    { 0x00, 0x00, 0x3B, 0x6E, 0x66, 0x06, 0x0F, 0x00},   // U+0072 (r)
+    { 0x00, 0x00, 0x3E, 0x03, 0x1E, 0x30, 0x1F, 0x00},   // U+0073 (s)
+    { 0x08, 0x0C, 0x3E, 0x0C, 0x0C, 0x2C, 0x18, 0x00},   // U+0074 (t)
+    { 0x00, 0x00, 0x33, 0x33, 0x33, 0x33, 0x6E, 0x00},   // U+0075 (u)
+    { 0x00, 0x00, 0x33, 0x33, 0x33, 0x1E, 0x0C, 0x00},   // U+0076 (v)
+    { 0x00, 0x00, 0x63, 0x6B, 0x7F, 0x7F, 0x36, 0x00},   // U+0077 (w)
+    { 0x00, 0x00, 0x63, 0x36, 0x1C, 0x36, 0x63, 0x00},   // U+0078 (x)
+    { 0x00, 0x00, 0x33, 0x33, 0x33, 0x3E, 0x30, 0x1F},   // U+0079 (y)
+    { 0x00, 0x00, 0x3F, 0x19, 0x0C, 0x26, 0x3F, 0x00},   // U+007A (z)
+    { 0x38, 0x0C, 0x0C, 0x07, 0x0C, 0x0C, 0x38, 0x00},   // U+007B ({)
+    { 0x18, 0x18, 0x18, 0x00, 0x18, 0x18, 0x18, 0x00},   // U+007C (|)
+    { 0x07, 0x0C, 0x0C, 0x38, 0x0C, 0x0C, 0x07, 0x00},   // U+007D (})
+    { 0x6E, 0x3B, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},   // U+007E (~)
+    { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}    // U+007F
+};
diff --git a/main.c b/main.c
new file mode 100644
index 0000000..654e188
--- /dev/null
+++ b/main.c
@@ -0,0 +1,75 @@
+#include <stdio.h>
+#include "st7735.h"
+#include <wiringPi.h>
+
+int main(int argc, char *argv[])
+{
+	setbuf(stdout, NULL);
+
+	wiringPiSetup();
+
+	lcd_t* lcd = lcd_init(40000000, 10, 2, 0);
+
+	printf("Fill display...");
+	printf("blue...");
+	lcd_fillScreen(0, 70, 160);
+	delay(1000);
+	printf("black...");
+	lcd_fillScreen(0, 0, 0);
+	printf("DONE\n");
+	delay(1000);
+
+	/* Draw the lines */
+	/*printf("Lines...");
+	lcdst_drawHLine(0, 149, 128, 0, 255, 255);
+	lcdst_drawHLine(0, 139, 128, 255, 255, 0);
+	lcdst_drawVLine(117, 0, 160, 0, 255, 255);
+	lcdst_drawVLine(107, 0, 160, 255, 255, 0);
+	printf("DONE\n");*/
+
+	/*printf("Points...");
+	for (int i = 1; i < 20; i++) {
+		lcdst_drawPx(5 - 1, 70 + i, 100, 100, 100);
+		lcdst_drawPx(5 + i + 1, 70 + i, 100, 100, 100);
+	}
+	printf("DONE\n");
+	
+	printf("Triangle...");
+	for (int i = 1; i < 20; i++) {
+		lcdst_drawHLine(5, 70 + i, i, 255, 0, 0);
+	}
+	printf("DONE\n");*/
+	
+	printf("Rectangles...");
+	//printf("outline...");
+	//lcd_drawRect(10, 10, 10, 10, 0, 255, 255);
+	//lcd_drawRect(10, 30, 10, 10, 255, 255, 0);
+	printf("filled...");
+	lcd_fillRect(30, 10, 10, 10, 0, 255, 255);
+	lcd_fillRect(30, 30, 10, 10, 255, 255, 0);
+	printf("bunch...");
+	for (int i = 0; i < 40; i++) {
+		lcd_fillRect(40 + (i%13) * 4, 40 + (i%19) * 4, 20, 20, i % 5 * 15, i % 7 * 17, i % 3 * 23);
+	}
+	printf("DONE\n");
+
+	printf("Text...");
+	lcd_printChar(10, 90, 'A');
+	lcd_printText(10, 50, "Ahoj!");
+	lcd_printChar(10, 100, 'Z');
+	printf("DONE\n");
+
+	/* Send the raw data */
+/*	printf("Raw...");
+	lcdst_setWindow(20, 20, 29, 29);
+	for(uint8 i=0; i<100; i++) lcdst_pushPx(255, 0, 255);
+	lcdst_setWindow(0, 0, 127, 159);
+	printf("DONE\n");*/
+	
+
+	/* Uninitialize the display */
+	//lcd_deinit(lcd);
+	
+	return 0;
+}
+
diff --git a/meson.build b/meson.build
new file mode 100644
index 0000000..75fd70a
--- /dev/null
+++ b/meson.build
@@ -0,0 +1,3 @@
+project('dejvino-ST7735', 'c')
+src = ['main.c', 'st7735.c']
+executable('st7735', src, link_args: '-lwiringPi')
diff --git a/st7735.c b/st7735.c
new file mode 100644
index 0000000..ca53f6b
--- /dev/null
+++ b/st7735.c
@@ -0,0 +1,332 @@
+#include <stdio.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include "st7735.h"
+#include "font8x8_basic.h"
+
+/********************************** EASY PORT *********************************/
+/*
+ * If you porting this code, you can change below headers and function pointers
+ * in gpio structure.
+ */
+#include <wiringPi.h>
+#include <wiringPiSPI.h>
+struct
+{
+	void (* const delay)(unsigned int milliseconds);
+	void (* const pinMode)(int pin, int mode);
+	void (* const digitalWrite)(int pin, int value);
+	int  (* const spiSetup)(int channel, int speed);
+	int  (* const spiDataRW)(int channel, uint8 *data, int length);
+} static const gpio =
+{
+	delay,
+	pinMode,
+	digitalWrite,
+	wiringPiSPISetup,
+	wiringPiSPIDataRW
+};
+/****************************** END EASY PORT END *****************************/
+
+/* The global variable that stores the pointer to the structure,
+ * with the current active display.
+ */
+static lcd_t *activeDisplay;
+
+/*
+ * Safe allocation of the memory block.
+ *
+ * Parameters:
+ *   size - Size of memory block to allocate.
+ *
+ * Return:
+ *   Pointer to the memory block. If an error occurs, stop the program.
+ */
+static inline void *safeMalloc(size_t size)
+{
+	void *memoryBlock = (void*) malloc(size);
+
+	/* Check the pointer */
+	if(memoryBlock == NULL)
+	{
+		fprintf(stderr, "Out of RAM memory!\n");
+		exit(EXIT_FAILURE);
+	}
+	
+	return memoryBlock;
+} /* safeMalloc */
+
+
+void lcd_setOrientation(uint8 orientation);
+void lcd_setGamma(uint8 state);
+void lcd_pushPx(uint8 r, uint8 g, uint8 b);
+void lcd_pushPixels(uint8* pixels, size_t count);
+void lcd_pushChar(char c);
+
+/*
+ * Write the command to the display driver.
+ *
+ * Parameters:
+ *   cmd - The command to write.
+ */
+static inline void writeCommand(uint8 cmd)
+{
+	gpio.digitalWrite(activeDisplay->a0, LOW);
+	gpio.spiDataRW(activeDisplay->cs, &cmd, 1);
+} /* writeCommand */
+
+/*
+ * Write the data to the display driver.
+ *
+ * Parameters:
+ *   data - The data to write.
+ */
+static inline void writeData(uint8 data)
+{
+	gpio.digitalWrite(activeDisplay->a0, HIGH);
+	gpio.spiDataRW(activeDisplay->cs, &data, 1);
+} /* writeData */
+
+lcd_t *lcd_init(int spiSpeed, int cs, int a0, int rs)
+{
+	/* Create the one instance of the lcdst_t structure and activate it */
+	lcd_t *instance = (lcd_t *) safeMalloc(sizeof(lcd_t));
+	
+	activeDisplay = instance;
+
+	/* Assign specific pins */
+	instance->cs = cs;
+	instance->a0 = a0;
+	instance->rs = rs;
+	/*
+	 * instance->width; instance->height
+	 * The setting of this variables will take place
+	 * in the function lcdst_setOrientation() below.
+	 */
+	
+	/* Configure the a0 pin. The logic level is not significant now. */
+	gpio.pinMode(instance->a0, OUTPUT);
+	
+	/* If the rs pin is connected then configure it */
+	if(instance->rs != -1)
+	{
+		gpio.pinMode(instance->rs, OUTPUT);
+		gpio.digitalWrite(instance->rs, HIGH); /* Reset OFF */
+		gpio.delay(10);
+	}
+	
+	/* Configure the SPI interface */
+	if(gpio.spiSetup(instance->cs, spiSpeed) == -1)
+	{
+		fprintf(stderr, "Failed to setup the SPI interface!\n");
+		exit(EXIT_FAILURE);
+	}
+
+	/* Software reset; Wait minimum 120ms */
+	writeCommand(0x01);
+	gpio.delay(150);
+	
+	/* Sleep out; Wait minimum 120ms */
+	writeCommand(0x11);
+	gpio.delay(150);
+	
+	/* Set the orientation and the gamma */
+	lcd_setOrientation(0);
+	lcd_setGamma(2); /* Optional */
+	
+	/* Set the pixel format */
+	writeCommand(0x3A);
+	writeData(0x06);
+	
+	/* Display ON; Wait 100ms before start */
+	writeCommand(0x29);
+	gpio.delay(100);
+	
+	return instance;
+} /* lcd_init */
+
+void lcd_deinit(lcd_t *display)
+{
+	if(display == NULL) return;
+	
+	free(display);
+} /* lcdst_uninit */
+
+void lcd_setOrientation(uint8 orientation)
+{
+	writeCommand(0x36); /* Memory Data Access Control */
+
+	switch(orientation)
+	{
+		case 1:
+			writeData(0x60); /* MX + MV */
+			activeDisplay->width  = 160;
+			activeDisplay->height = 128;
+			lcd_setWindow(0, 0, 159, 127);
+			break;
+
+		case 2:
+			writeData(0xC0); /* MY + MX */
+			activeDisplay->width  = 128;
+			activeDisplay->height = 160;
+			lcd_setWindow(0, 0, 127, 159);
+			break;
+
+		case 3:
+			writeData(0xA0); /* MY + MV */
+			activeDisplay->width  = 160;
+			activeDisplay->height = 128;
+			lcd_setWindow(0, 0, 159, 127);
+			break;
+
+		default:
+			writeData(0x00); /* None */
+			activeDisplay->width  = 128;
+			activeDisplay->height = 160;
+			lcd_setWindow(0, 0, 127, 159);
+			break;
+	}
+} /* lcdst_setOrientation */
+
+void lcd_setGamma(uint8 state)
+{
+	/* The status (0 or 1) of the GS pin can only be empirically tested */
+	switch(state)
+	{
+		case 1:  state = 2; break; /* GS_pin=1: 1.8; GS_pin=0: 2.5 */
+		case 2:  state = 4; break; /* GS_pin=1: 2.5; GS_pin=0: 2.2 */
+		case 3:  state = 8; break; /* GS_pin=1: 1.0; GS_pin=0: 1.8 */
+		default: state = 1; break; /* GS_pin=1: 2.2; GS_pin=0: 1.0 */
+	}
+	
+	/* Set built-in gamma */
+	writeCommand(0x26);
+	writeData(state);
+} /* lcdst_setGamma */
+
+void lcd_setInversion(uint8 state)
+{
+	/* Display inversion ON/OFF */
+	writeCommand(state ? 0x21 : 0x20);
+} /* lcdst_setInversion */
+
+uint8 lcd_setWindow(uint8 x1, uint8 y1, uint8 x2, uint8 y2)
+{
+	/* Accept: 0 <= x1 <= x2 < activeDisplay->width */
+	if(x2 < x1) return 1;
+	if(x2 >= activeDisplay->width) return 1;
+	
+	/* Accept: 0 <= y1 <= y2 < activeDisplay->height */
+	if(y2 < y1) return 1;
+	if(y2 >= activeDisplay->height) return 1;
+	
+	/* Set column address */
+	writeCommand(0x2A);
+	writeData(0); writeData(x1);
+	writeData(0); writeData(x2);
+	
+	/* Set row address */
+	writeCommand(0x2B);
+	writeData(0); writeData(y1);
+	writeData(0); writeData(y2);
+	
+	/* Activate RAW write */
+	writeCommand(0x2C);
+	//gpio.delay(5);
+	
+	return 0;
+} /* lcdst_setWindow */
+
+void lcd_activateRamWrite(void)
+{
+	writeCommand(0x2C);
+	//gpio.delay(5);
+} /* lcdst_activateRamWrite */
+
+uint8 pixel[3];
+
+inline void lcd_pushPx(uint8 r, uint8 g, uint8 b)
+{
+	gpio.digitalWrite(activeDisplay->a0, HIGH);
+	pixel[0] = r;
+	pixel[1] = g;
+	pixel[2] = b;
+	gpio.spiDataRW(activeDisplay->cs, pixel, 3);
+} /* lcdst_pushPx */
+
+void lcd_pushPixels(uint8* pixels, size_t count)
+{
+	gpio.digitalWrite(activeDisplay->a0, HIGH);
+	gpio.spiDataRW(activeDisplay->cs, pixels, count * 3);
+}
+
+void lcd_drawPx(uint8 x, uint8 y, uint8 r, uint8 g, uint8 b)
+{
+	if(lcd_setWindow(x, y, x, y)) return;
+	lcd_pushPx(r, g, b);
+} /* lcdst_drawPx */
+
+void lcd_fillRect(uint8 x, uint8 y, uint8 w, uint8 h,
+					uint8 r, uint8 g, uint8 b)
+{
+	/* Draw only in the display space */
+	if((w == 0) || (h == 0)) return;
+	if((x+w-1) >= activeDisplay->width)  w = activeDisplay->width  - x;
+	if((y+h-1) >= activeDisplay->height) h = activeDisplay->height - y;
+	
+	/* Draw the filled rectangle */
+	if(lcd_setWindow(x, y, x+w-1, y+h-1)) return;
+
+#define BUFFER_PIXELS 64
+	int wh = w*h;
+	uint8 buffer[BUFFER_PIXELS * sizeof(uint8) * 3];
+	for (int p = 0; p < wh; p += BUFFER_PIXELS) {
+		for(int pb = 0; pb < BUFFER_PIXELS; pb++) {
+			buffer[pb * 3 + 0] = r;
+			buffer[pb * 3 + 1] = g;
+			buffer[pb * 3 + 2] = b;
+		}
+		int rem = wh - p;
+		lcd_pushPixels(buffer, ((rem < BUFFER_PIXELS) ? rem : BUFFER_PIXELS));
+	}
+}
+
+void lcd_fillScreen(uint8 r, uint8 g, uint8 b)
+{
+	/* Fill the whole screen with one color */
+	lcd_fillRect(0, 0, activeDisplay->width, activeDisplay->height, r, g, b);
+} /* lcdst_drawScreen */
+
+void lcd_pushChar(char c)
+{
+	char* bitmap = font8x8_basic[(unsigned int) c];
+	int x,y;
+	int set;
+	int mask;
+	for (x=0; x < 8; x++) {
+	    for (y=0; y < 8; y++) {
+	        set = bitmap[x] & 1 << y;
+	        printf("%c", set ? 'X' : ' ');
+		if (set) {
+			lcd_pushPx(200, 0, 0);
+		} else {
+			lcd_pushPx(0, 0, 0);
+		}
+	    }
+	    printf("\n");
+	}
+}
+
+void lcd_printChar(uint8 x, uint8 y, char c)
+{
+	lcd_setWindow(x, y, x+8 - 1, y+8 - 1);
+	lcd_pushChar(c);
+}
+
+void lcd_printText(uint8 x, uint8 y, char* text)
+{
+	for (int i = 0; i < strlen(text); i++) {
+		lcd_printChar(x + i * 8, y, text[i]);
+	}
+}
+
diff --git a/st7735.h b/st7735.h
new file mode 100644
index 0000000..5211478
--- /dev/null
+++ b/st7735.h
@@ -0,0 +1,100 @@
+#ifndef uint8
+#define uint8 unsigned char
+#endif
+ 
+typedef struct
+{
+	int cs, a0, rs;
+	uint8 width, height;
+} lcd_t;
+
+/*
+ * Initialize the display and create a data structure for it.
+ * The last initialized display is active.
+ *
+ * Parameters:
+ *   spiSpeed - Speed of the SPI interface.
+ *   cs - Chip selection pin.
+ *   a0 - Data/Command pin.
+ *   rs - Optional reset pin. If you do not use it, enter -1.
+ *
+ * Return: Pointer to the structure with display data.
+ *
+ */
+lcd_t *lcd_init(int spiSpeed, int cs, int a0, int rs);
+
+/*
+ * Reset the specified display and clear the previously assigned memory.
+ *
+ * Parameters:
+ *   display - Pointer to the structure with display data.
+ *
+ * Return: void
+ */
+void lcd_deinit(lcd_t *display);
+
+/*
+ * Set the drawing area on the currently active display.
+ *
+ * Parameters:
+ *   x1 - The X parameter of the first point.
+ *   y1 - The Y parameter of the first point.
+ *   x2 - The X parameter of the second point.
+ *   y2 - The Y parameter of the second point.
+ *
+ * Return: Confirmation of the occurrence or non-occurrence of an error.
+ * 0 - The error did not occur; 1 - The error occurred.
+ *
+ */
+uint8 lcd_setWindow(uint8 x1, uint8 y1, uint8 x2, uint8 y2);
+
+/*
+ * Draw one pixel on the currently active display.
+ * The color intensity scale for a normal pixel is from 0 to 255.
+ * The color intensity scale for the reduced pixel is from 0 to 15.
+ *
+ * Parameters:
+ *   x - The X parameter of the pixel.
+ *   y - The Y parameter of the pixel.
+ *   r - The intensity of the red color.
+ *   g - The intensity of the green color.
+ *   b - The intensity of the blue color.
+ *
+ * Return: void
+ */
+void lcd_drawPx(uint8 x, uint8 y, uint8 r, uint8 g, uint8 b);
+
+/*
+ * Draw a filled rectangle on the currently active display.
+ * The color intensity scale for a normal pixel is from 0 to 255.
+ * The color intensity scale for the reduced pixel is from 0 to 15.
+ *
+ * Parameters:
+ *   x - Parameter X of the upper left corner of the rectangle.
+ *   y - Parameter Y of the upper left corner of the rectangle.
+ *   w - The width of the rectangle.
+ *   h - The height of the rectangle.
+ *   r - The intensity of the red color.
+ *   g - The intensity of the green color.
+ *   b - The intensity of the blue color.
+ *
+ * Return: void
+ */
+void lcd_fillRect(uint8 x, uint8 y, uint8 w, uint8 h, uint8 r, uint8 g, uint8 b);
+
+/*
+ * Fill the entire screen with one color of the currently active display.
+ * The color intensity scale for a normal pixel is from 0 to 255.
+ * The color intensity scale for the reduced pixel is from 0 to 15.
+ *
+ * Parameters:
+ *   r - The intensity of the red color.
+ *   g - The intensity of the green color.
+ *   b - The intensity of the blue color.
+ *
+ * Return: void
+ */
+void lcd_fillScreen(uint8 r, uint8 g, uint8 b);
+
+void lcd_printChar(uint8 x, uint8 y, char c);
+void lcd_printText(uint8 x, uint8 y, char* text);