1/*
  2 *    Filename: cfag12864b-example.c
  3 *     Version: 0.1.0
  4 * Description: cfag12864b LCD userspace example program
  5 *     License: GPLv2
  6 *
  7 *      Author: Copyright (C) Miguel Ojeda Sandonis
  8 *        Date: 2006-10-31
  9 *
 10 *  This program is free software; you can redistribute it and/or modify
 11 *  it under the terms of the GNU General Public License version 2 as
 12 *  published by the Free Software Foundation.
 13 *
 14 *  This program is distributed in the hope that it will be useful,
 15 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 16 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 17 *  GNU General Public License for more details.
 18 *
 19 *  You should have received a copy of the GNU General Public License
 20 *  along with this program; if not, write to the Free Software
 21 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 22 *
 23 */
 24
 25/*
 26 * ------------------------
 27 * start of cfag12864b code
 28 * ------------------------
 29 */
 30
 31#include <string.h>
 32#include <fcntl.h>
 33#include <unistd.h>
 34#include <sys/types.h>
 35#include <sys/stat.h>
 36#include <sys/mman.h>
 37
 38#define CFAG12864B_WIDTH		(128)
 39#define CFAG12864B_HEIGHT		(64)
 40#define CFAG12864B_SIZE			(128 * 64 / 8)
 41#define CFAG12864B_BPB			(8)
 42#define CFAG12864B_ADDRESS(x, y)	((y) * CFAG12864B_WIDTH / \
 43					CFAG12864B_BPB + (x) / CFAG12864B_BPB)
 44#define CFAG12864B_BIT(n)		(((unsigned char) 1) << (n))
 45
 46#undef CFAG12864B_DOCHECK
 47#ifdef CFAG12864B_DOCHECK
 48	#define CFAG12864B_CHECK(x, y)		((x) < CFAG12864B_WIDTH && \
 49						(y) < CFAG12864B_HEIGHT)
 50#else
 51	#define CFAG12864B_CHECK(x, y)		(1)
 52#endif
 53
 54int cfag12864b_fd;
 55unsigned char * cfag12864b_mem;
 56unsigned char cfag12864b_buffer[CFAG12864B_SIZE];
 57
 58/*
 59 * init a cfag12864b framebuffer device
 60 *
 61 * No error:       return = 0
 62 * Unable to open: return = -1
 63 * Unable to mmap: return = -2
 64 */
 65static int cfag12864b_init(char *path)
 66{
 67	cfag12864b_fd = open(path, O_RDWR);
 68	if (cfag12864b_fd == -1)
 69		return -1;
 70
 71	cfag12864b_mem = mmap(0, CFAG12864B_SIZE, PROT_READ | PROT_WRITE,
 72		MAP_SHARED, cfag12864b_fd, 0);
 73	if (cfag12864b_mem == MAP_FAILED) {
 74		close(cfag12864b_fd);
 75		return -2;
 76	}
 77
 78	return 0;
 79}
 80
 81/*
 82 * exit a cfag12864b framebuffer device
 83 */
 84static void cfag12864b_exit(void)
 85{
 86	munmap(cfag12864b_mem, CFAG12864B_SIZE);
 87	close(cfag12864b_fd);
 88}
 89
 90/*
 91 * set (x, y) pixel
 92 */
 93static void cfag12864b_set(unsigned char x, unsigned char y)
 94{
 95	if (CFAG12864B_CHECK(x, y))
 96		cfag12864b_buffer[CFAG12864B_ADDRESS(x, y)] |=
 97			CFAG12864B_BIT(x % CFAG12864B_BPB);
 98}
 99
100/*
101 * unset (x, y) pixel
102 */
103static void cfag12864b_unset(unsigned char x, unsigned char y)
104{
105	if (CFAG12864B_CHECK(x, y))
106		cfag12864b_buffer[CFAG12864B_ADDRESS(x, y)] &=
107			~CFAG12864B_BIT(x % CFAG12864B_BPB);
108}
109
110/*
111 * is set (x, y) pixel?
112 *
113 * Pixel off: return = 0
114 * Pixel on:  return = 1
115 */
116static unsigned char cfag12864b_isset(unsigned char x, unsigned char y)
117{
118	if (CFAG12864B_CHECK(x, y))
119		if (cfag12864b_buffer[CFAG12864B_ADDRESS(x, y)] &
120			CFAG12864B_BIT(x % CFAG12864B_BPB))
121			return 1;
122
123	return 0;
124}
125
126/*
127 * not (x, y) pixel
128 */
129static void cfag12864b_not(unsigned char x, unsigned char y)
130{
131	if (cfag12864b_isset(x, y))
132		cfag12864b_unset(x, y);
133	else
134		cfag12864b_set(x, y);
135}
136
137/*
138 * fill (set all pixels)
139 */
140static void cfag12864b_fill(void)
141{
142	unsigned short i;
143
144	for (i = 0; i < CFAG12864B_SIZE; i++)
145		cfag12864b_buffer[i] = 0xFF;
146}
147
148/*
149 * clear (unset all pixels)
150 */
151static void cfag12864b_clear(void)
152{
153	unsigned short i;
154
155	for (i = 0; i < CFAG12864B_SIZE; i++)
156		cfag12864b_buffer[i] = 0;
157}
158
159/*
160 * format a [128*64] matrix
161 *
162 * Pixel off: src[i] = 0
163 * Pixel on:  src[i] > 0
164 */
165static void cfag12864b_format(unsigned char * matrix)
166{
167	unsigned char i, j, n;
168
169	for (i = 0; i < CFAG12864B_HEIGHT; i++)
170	for (j = 0; j < CFAG12864B_WIDTH / CFAG12864B_BPB; j++) {
171		cfag12864b_buffer[i * CFAG12864B_WIDTH / CFAG12864B_BPB +
172			j] = 0;
173		for (n = 0; n < CFAG12864B_BPB; n++)
174			if (matrix[i * CFAG12864B_WIDTH +
175				j * CFAG12864B_BPB + n])
176				cfag12864b_buffer[i * CFAG12864B_WIDTH /
177					CFAG12864B_BPB + j] |=
178					CFAG12864B_BIT(n);
179	}
180}
181
182/*
183 * blit buffer to lcd
184 */
185static void cfag12864b_blit(void)
186{
187	memcpy(cfag12864b_mem, cfag12864b_buffer, CFAG12864B_SIZE);
188}
189
190/*
191 * ----------------------
192 * end of cfag12864b code
193 * ----------------------
194 */
195
196#include <stdio.h>
197
198#define EXAMPLES	6
199
200static void example(unsigned char n)
201{
202	unsigned short i, j;
203	unsigned char matrix[CFAG12864B_WIDTH * CFAG12864B_HEIGHT];
204
205	if (n > EXAMPLES)
206		return;
207
208	printf("Example %i/%i - ", n, EXAMPLES);
209
210	switch (n) {
211	case 1:
212		printf("Draw points setting bits");
213		cfag12864b_clear();
214		for (i = 0; i < CFAG12864B_WIDTH; i += 2)
215			for (j = 0; j < CFAG12864B_HEIGHT; j += 2)
216				cfag12864b_set(i, j);
217		break;
218
219	case 2:
220		printf("Clear the LCD");
221		cfag12864b_clear();
222		break;
223
224	case 3:
225		printf("Draw rows formatting a [128*64] matrix");
226		memset(matrix, 0, CFAG12864B_WIDTH * CFAG12864B_HEIGHT);
227		for (i = 0; i < CFAG12864B_WIDTH; i++)
228			for (j = 0; j < CFAG12864B_HEIGHT; j += 2)
229				matrix[j * CFAG12864B_WIDTH + i] = 1;
230		cfag12864b_format(matrix);
231		break;
232
233	case 4:
234		printf("Fill the lcd");
235		cfag12864b_fill();
236		break;
237
238	case 5:
239		printf("Draw columns unsetting bits");
240		for (i = 0; i < CFAG12864B_WIDTH; i += 2)
241			for (j = 0; j < CFAG12864B_HEIGHT; j++)
242				cfag12864b_unset(i, j);
243		break;
244
245	case 6:
246		printf("Do negative not-ing all bits");
247		for (i = 0; i < CFAG12864B_WIDTH; i++)
248			for (j = 0; j < CFAG12864B_HEIGHT; j ++)
249				cfag12864b_not(i, j);
250		break;
251	}
252
253	puts(" - [Press Enter]");
254}
255
256int main(int argc, char *argv[])
257{
258	unsigned char n;
259
260	if (argc != 2) {
261		printf(
262			"Sintax:  %s fbdev\n"
263			"Usually: /dev/fb0, /dev/fb1...\n", argv[0]);
264		return -1;
265	}
266
267	if (cfag12864b_init(argv[1])) {
268		printf("Can't init %s fbdev\n", argv[1]);
269		return -2;
270	}
271
272	for (n = 1; n <= EXAMPLES; n++) {
273		example(n);
274		cfag12864b_blit();
275		while (getchar() != '\n');
276	}
277
278	cfag12864b_exit();
279
280	return 0;
281}