About Kernel Documentation Linux Kernel Contact Linux Resources Linux Blog

Documentation / auxdisplay / cfag12864b-example.c




Custom Search

Based on kernel version 3.15.4. Page generated on 2014-07-07 08:59 EST.

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	
54	int cfag12864b_fd;
55	unsigned char * cfag12864b_mem;
56	unsigned 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	 */
65	static 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	 */
84	static void cfag12864b_exit(void)
85	{
86		munmap(cfag12864b_mem, CFAG12864B_SIZE);
87		close(cfag12864b_fd);
88	}
89	
90	/*
91	 * set (x, y) pixel
92	 */
93	static 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	 */
103	static 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	 */
116	static 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	 */
129	static 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	 */
140	static 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	 */
151	static 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	 */
165	static 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	 */
185	static 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	
200	static 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	
256	int 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	}
Hide Line Numbers
About Kernel Documentation Linux Kernel Contact Linux Resources Linux Blog

Information is copyright its respective author. All material is available from the Linux Kernel Source distributed under a GPL License. This page is provided as a free service by mjmwired.net.