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}
282