File: serialVFD.c

package info (click to toggle)
lcdproc 0.5.9-3
  • links: PTS, VCS
  • area: main
  • in suites: bullseye, buster, sid
  • size: 5,064 kB
  • sloc: ansic: 59,645; sh: 1,740; perl: 681; makefile: 417
file content (888 lines) | stat: -rw-r--r-- 26,540 bytes parent folder | download
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
/** \file server/drivers/serialVFD.c
 * LCDd \c serialVFD driver for various serial (& parallel) VFD devices.
 *
 * The driver should operate most of NEC, Futaba and Noritake 7x5 dot VFDs
 * with serial(rs232) and/or parallel interface. See
 * /docs/lcdproc-user/serialvfd-howto.html for further information.
 *
 * This driver consists of three parts:
 * \li This file \c serialVFD.c implements most the driver API.
 * \li \c serialVFD_io.c implements low-level I/O functions for serial and
 * parallel ports.
 * \li \c serialVFD_displays.c initializes display-specific character mappings
 * and command sequences.
 */

/*-
 * Copyright (C) 2006 Stefan Herdler
 *
 * This driver is based on wirz-sli.c, hd44780.c, drv_base.c and NoritakeVFD
 * driver. It may contain parts of other drivers of this package too.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301
 */

/*
 * 2006-05-16 Version 0.3: everything should work (not all hardware tested!)
 */

#ifdef HAVE_CONFIG_H
# include "config.h"
#endif

#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <termios.h>
#include <string.h>

#include "lcd.h"
#include "shared/report.h"
#include "lcd_lib.h"
#include "adv_bignum.h"
#include "serialVFD.h"
#include "serialVFD_displays.h"
#include "serialVFD_io.h"

/*
 * This file uses __FUNCTION__ in debug() and drvthis->name in report() calls.
 */

#define pos1_cursor	4 //moves cursor to top left character.
#define mv_cursor	5 //moves cursor to position specified by the next byte.
#define reset		6 //reset
#define init_cmds	7 //commands needed to initialize the display.
#define set_user_char	8 //set user character.
#define hor_tab		9 //moves cursor 1 chr right
#define next_line	10 //moves cursor to the first character of the next line (= LF + CR)

/* Vars for the server core */
MODULE_EXPORT char *api_version = API_VERSION;
MODULE_EXPORT int stay_in_foreground = 0;
MODULE_EXPORT int supports_multiple = 0;
MODULE_EXPORT char *symbol_prefix = "serialVFD_";

/* Internal functions */
static void serialVFD_init_vbar (Driver *drvthis);
static void serialVFD_init_hbar (Driver *drvthis);
static void serialVFD_put_char (Driver *drvthis, int n);
static void serialVFD_hw_write (Driver *drvthis, int i);


/**
 * Initialize the driver.
 * Open com port and set baud correctly...
 * \param drvthis  Pointer to driver structure.
 * \retval 0       Success.
 * \retval <0      Error.
 */
MODULE_EXPORT int
serialVFD_init (Driver *drvthis)
{
	int tmp, w, h;
	char size[200] = DEFAULT_SIZE;

	PrivateData *p;

	debug(RPT_INFO, "%s(%p)", __FUNCTION__, drvthis);

	/* Allocate and store private data */
	p = (PrivateData *) calloc(1, sizeof(PrivateData));
	if (p == NULL)
		return -1;
	if (drvthis->store_private_ptr(drvthis, p))
		return -1;

	/* Initialize the PrivateData structure */
	p->cellwidth = DEFAULT_CELL_WIDTH;
	p->cellheight = DEFAULT_CELL_HEIGHT;
	p->ccmode = standard;
	p->ISO_8859_1 = 1;
	p->refresh_timer = 480;
	p->hw_brightness = 0;
	p->para_wait = DEFAULT_PARA_WAIT;
	p->hw_cmd[next_line][0] = 0;	/* disable line / set normal mode */

	/* Connection type: parallel or serial? */
	p->use_parallel	= drvthis->config_get_bool(drvthis->name, "use_parallel", 0, 0);

	/* Which device should be used */
	strncpy(p->device, drvthis->config_get_string(drvthis->name, "Device", 0, DEFAULT_DEVICE), sizeof(p->device));
	p->device[sizeof(p->device)-1] = '\0';
	report(RPT_INFO, "%s: using Device %s", drvthis->name, p->device);

	if (p->use_parallel) {
		p->port	= drvthis->config_get_int(drvthis->name, "port", 0, DEFAULT_LPTPORT);
	}
	else {
		/* Which speed */
		tmp = drvthis->config_get_int(drvthis->name, "Speed", 0, DEFAULT_SPEED);
		if ((tmp != 1200) && (tmp != 2400) && (tmp != 9600) && (tmp != 19200) && (tmp != 115200)) {
			report(RPT_WARNING, "%s: Speed must be 1200, 2400, 9600, 19200 or 115200. Using default %d",
				drvthis->name, DEFAULT_SPEED);
			tmp = DEFAULT_SPEED;
		}
		if (tmp == 1200) p->speed = B1200;
		else if (tmp == 2400) p->speed = B2400;
		else if (tmp == 9600) p->speed = B9600;
		else if (tmp == 19200) p->speed = B19200;
		else if (tmp == 115200) p->speed = B115200;
	}

	/* Which size */
	strncpy(size, drvthis->config_get_string(drvthis->name, "Size", 0, DEFAULT_SIZE), sizeof(size));
	size[sizeof(size)-1] = '\0';
	if ((sscanf(size, "%dx%d", &w, &h) != 2)
	    || (w <= 0) || (w > LCD_MAX_WIDTH)
	    || (h <= 0) || (h > LCD_MAX_HEIGHT)) {
		report(RPT_WARNING, "%s: cannot parse size: %s; using default %s",
			drvthis->name, size, DEFAULT_SIZE);
		sscanf(DEFAULT_SIZE, "%dx%d", &w, &h);
	}
	p->width = w;
	p->height = h;

	/* Which backlight brightness */
	tmp = drvthis->config_get_int(drvthis->name, "Brightness", 0, DEFAULT_ON_BRIGHTNESS);
	debug(RPT_INFO, "%s: Brightness (in config) is '%d'", __FUNCTION__, tmp);
	if ((tmp < 0) || (tmp > 1000)) {
		report(RPT_WARNING, "%s: Brightness must be between 0 and 1000; using default %d",
			drvthis->name, DEFAULT_ON_BRIGHTNESS);
		tmp = DEFAULT_ON_BRIGHTNESS;
	}
	p->on_brightness = tmp;

	/* Which backlight-off "brightness" */
	tmp = drvthis->config_get_int(drvthis->name, "OffBrightness", 0, DEFAULT_OFF_BRIGHTNESS);
	debug(RPT_INFO, "%s: OffBrightness (in config) is '%d'", __FUNCTION__, tmp);
	if ((tmp < 0) || (tmp > 1000)) {
		report(RPT_WARNING, "%s: OffBrightness must be between 0 and 1000; using default %d",
			drvthis->name, DEFAULT_OFF_BRIGHTNESS);
		tmp = DEFAULT_OFF_BRIGHTNESS;
	}
	p->off_brightness = tmp;

	/* ISO 8859 1 */
	p->ISO_8859_1 = drvthis->config_get_bool(drvthis->name, "ISO_8859_1", 0, 1);

	/* Which displaytype */
	p->display_type = drvthis->config_get_int(drvthis->name, "Type", 0, DEFAULT_DISPLAYTYPE);

	/* Number of custom characters */
	tmp = drvthis->config_get_int(drvthis->name, "Custom-Characters", 0, CC_UNSET);
	if ((tmp < 0) || (tmp > 99)) {
		report(RPT_WARNING, "%s: The number of Custom-Characters must be between 0 and 99. Using default",
			drvthis->name, 0);
		tmp = CC_UNSET;
	}
	p->customchars = tmp;

	/* Do connection type specific io-port init */
	if (Port_Function[p->use_parallel].init_fkt(drvthis) == -1) {
		report(RPT_ERR, "%s: unable to initialize io-port", drvthis->name);
		return -1;
	}

	/* make sure the frame buffer is there... */
	p->framebuf = (unsigned char *) malloc(p->width * p->height);
	if (p->framebuf == NULL) {
		report(RPT_ERR, "%s: unable to create framebuffer", drvthis->name);
		return -1;
	}
	memset(p->framebuf, ' ', p->width * p->height);

	/* make sure the framebuffer backing store is there... */
	p->backingstore = (unsigned char *) malloc(p->width * p->height);
	if (p->backingstore == NULL) {
		report(RPT_ERR, "%s: unable to create framebuffer backing store", drvthis->name);
		return -1;
	}
	memset(p->backingstore, 0, p->width * p->height);

	/* setup displayspecific data */
	memset(p->usr_chr_mapping, 0, 31);	/* no character mapping by default */
	memset(p->usr_chr_load_mapping, 0, 31);
	if (serialVFD_load_display_data(drvthis) != 0) {
		report(RPT_WARNING, "%s: Type %d not defined; using default %d",
			drvthis->name, p->display_type, DEFAULT_DISPLAYTYPE);
		p->display_type = DEFAULT_DISPLAYTYPE;
		if (serialVFD_load_display_data(drvthis) != 0) {
			report(RPT_ERR, "%s: unable to load display_data", drvthis->name);
			return -1;
		}
	}

	/* Things to set up after loading display specific data */

	/* parallel port wait, overwrites value set by display specific data */
	tmp = p->para_wait;
	p->para_wait = drvthis->config_get_int(drvthis->name, "PortWait", 0, p->para_wait);

	/* load user defined character mapping table */
	if ((p->usr_chr_load_mapping[0] == 0) && (p->usr_chr_load_mapping[1] == 0)){ //this should not happen if usr_chr_load_mapping had been set
		memcpy(p->usr_chr_load_mapping, p->usr_chr_mapping, 31);
	}

	/* initialise display */
	Port_Function[p->use_parallel].write_fkt(drvthis, &p->hw_cmd[reset][1],p->hw_cmd[reset][0]);
	Port_Function[p->use_parallel].write_fkt(drvthis, &p->hw_cmd[init_cmds][1],p->hw_cmd[init_cmds][0]);
	serialVFD_backlight(drvthis, 1);

	report(RPT_DEBUG, "%s: init() done", drvthis->name);
	return 0;
}


/**
 * Close the driver (do necessary clean-up).
 * \param drvthis  Pointer to driver structure.
 */
MODULE_EXPORT void
serialVFD_close (Driver *drvthis)
{
	PrivateData *p = drvthis->private_data;
	if (p != NULL) {
		Port_Function[p->use_parallel].close_fkt(drvthis);
		if (p->framebuf)
			free(p->framebuf);
		if (p->backingstore)
			free(p->backingstore);
		free(p);
	}

	drvthis->store_private_ptr(drvthis, NULL);
}


/**
 * Return the display width in characters.
 * \param drvthis  Pointer to driver structure.
 * \return         Number of characters the display is wide.
 */
MODULE_EXPORT int
serialVFD_width (Driver *drvthis)
{
	PrivateData *p = drvthis->private_data;

	return p->width;
}


/**
 * Return the display height in characters.
 * \param drvthis  Pointer to driver structure.
 * \return         Number of characters the display is high.
 */
MODULE_EXPORT int
serialVFD_height (Driver *drvthis)
{
	PrivateData *p = drvthis->private_data;

	return p->height;
}


/**
 * Return the width of a character in pixels.
 * \param drvthis  Pointer to driver structure.
 * \return         Number of pixel columns a character cell is wide.
 */
MODULE_EXPORT int
serialVFD_cellwidth (Driver *drvthis)
{
	PrivateData *p = drvthis->private_data;

	return p->cellwidth;
}


/**
 * Return the height of a character in pixels.
 * \param drvthis  Pointer to driver structure.
 * \return         Number of pixel lines a character cell is high.
 */
MODULE_EXPORT int
serialVFD_cellheight (Driver *drvthis)
{
	PrivateData *p = drvthis->private_data;

	return p->cellheight;
}


/**
 * Clear the screen.
 * \param drvthis  Pointer to driver structure.
 */
MODULE_EXPORT void
serialVFD_clear (Driver *drvthis)
{
	PrivateData *p = drvthis->private_data;

	memset(p->framebuf, ' ', p->width * p->height);

}


/**
 * Flush data on screen to the VFD.
 * \param drvthis  Pointer to driver structure.
 */
MODULE_EXPORT void
serialVFD_flush (Driver *drvthis)
{
	PrivateData *p = drvthis->private_data;
	int i, j, last_chr = -10;
	char custom_char_changed[32]={0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};


	for (i = 0; i < p->customchars; i++) {
		for (j = 0; j < p->usr_chr_dot_assignment[0]; j++) {
			if (p->custom_char[i][j] != p->custom_char_store[i][j]) {
				custom_char_changed[i] = 1;
			}
			p->custom_char_store[i][j] = p->custom_char[i][j];
		}
	}

	/* Do a full refresh every 500 refreshs. */
	if (p->refresh_timer > 500) {
		/* With this it is possible to switch the display on and off
		 * while LCDd is running. */
		Port_Function[p->use_parallel].write_fkt(drvthis, &p->hw_cmd[init_cmds][1],p->hw_cmd[init_cmds][0]);

		Port_Function[p->use_parallel].write_fkt(drvthis, &p->hw_cmd[p->hw_brightness][1],\
		p->hw_cmd[p->hw_brightness][0]);	/* restore brightness */

		memset(p->backingstore, 0, p->width * p->height);	/* clear Backing-store */

		for (i = 0; i < p->customchars; i++)	/* refresh all customcharacters */
			custom_char_changed[i] = 1;
		p->refresh_timer = 0;
	}

	p->refresh_timer++;

	if (p->display_type == 1) {	/* KD Rev 2.1 only */
		if (custom_char_changed[p->last_custom])
			p->last_custom = -10;
	}
	else {			/* other Displays */
		for (i = 0; i < p->customchars; i++)	/* set customcharacters */
			if (custom_char_changed[i])
				serialVFD_put_char(drvthis, i);
	}

	/* normal mode Display */
	if (p->hw_cmd[next_line][0] == 0) {
		/* Workaround for Displays that doesn't support mv_cursor
		 * command */
		if (p->hw_cmd[mv_cursor][0] == 0) {
			Port_Function[p->use_parallel].write_fkt(drvthis, &p->hw_cmd[pos1_cursor][1], p->hw_cmd[pos1_cursor][0]);
			last_chr = -1;
		}

		for (i = 0; i < (p->height * p->width); i++) {
			/*
			 * Backing-store implementation.  If it's already
			 * on the screen, don't put it there again.
			 */
			if ((p->framebuf[i] != p->backingstore[i]) || (p->hw_cmd[hor_tab][0] == 0) ||
			((p->framebuf[i] <= 30) && (custom_char_changed[(int)p->framebuf[i]] != 0))) {
				if (last_chr < i-1) {	/* if not last char written cursor has to be moved. */
					if (((p->hw_cmd[hor_tab][0] * (i-1-last_chr)) > (p->hw_cmd[mv_cursor][0]+1)) && (p->hw_cmd[mv_cursor][0] != 0)) {
						Port_Function[p->use_parallel].write_fkt(drvthis, &p->hw_cmd[mv_cursor][1],
							p->hw_cmd[mv_cursor][0]);
						Port_Function[p->use_parallel].write_fkt(drvthis, (unsigned char *) &i, 1);
						debug(RPT_DEBUG, "%s: move  %d", __FUNCTION__, i);
					}
					else {
						for (j = last_chr; j < (i-1); j++)
							Port_Function[p->use_parallel].write_fkt(drvthis, &p->hw_cmd[hor_tab][1], p->hw_cmd[hor_tab][0]);
						debug(RPT_DEBUG, "%s: TAB  %d", __FUNCTION__, j-last_chr);
					}
				}
				serialVFD_hw_write(drvthis, i);
				last_chr = i;
			}
		}
	}
	/* line mode Display (partitially borrowed from serialPOS.c) */
	else {
		for (j = 0; j < p->height; j++) {
			/* set pointers to start of the line in frame buffer
			 * & backing store */
			unsigned char *sp = p->framebuf + (j * p->width);
			unsigned char *sq = p->backingstore + (j * p->width);
			/* Move to start of line */
			if (j == 0) {
				Port_Function[p->use_parallel].write_fkt(drvthis, &p->hw_cmd[pos1_cursor][1], p->hw_cmd[pos1_cursor][0]);
			}
			else {
				Port_Function[p->use_parallel].write_fkt(drvthis, &p->hw_cmd[next_line][1], p->hw_cmd[next_line][0]);
			}
			/* skip over identical lines */
			if (memcmp(sp, sq, p->width) == 0) {
				continue;
			}
			/* write the data */
			for (i = 0; i < p->width; i++) {
				serialVFD_hw_write(drvthis, (i + (j * p->width)));
			}
			last_chr = 10;
		}
	}

	/* update backingstore if something changed */
	if (last_chr >= 0) {
		memcpy(p->backingstore, p->framebuf, p->height * p->width);
		debug(RPT_DEBUG, "%s: memcpy", __FUNCTION__);
	}
}


/**
 * Print a string on the screen at position (x,y).
 * The upper-left corner is (1,1), the lower-right corner is (p->width, p->height).
 * \param drvthis  Pointer to driver structure.
 * \param x        Horizontal character position (column).
 * \param y        Vertical character position (row).
 * \param string   String that gets written.
 */
MODULE_EXPORT void
serialVFD_string (Driver *drvthis, int x, int y, const char string[])
{
	PrivateData *p = drvthis->private_data;
	int i;

	x--;
	y--;
	for (i = 0; string[i] != '\0'; i++) {
		/* Check for buffer overflows... */
		if ((y * p->width) + x + i > (p->width * p->height))
			break;
		p->framebuf[(y * p->width) + x + i] = string[i];
	}
}


/**
 * Print a character on the screen at position (x,y).
 * The upper-left corner is (1,1), the lower-right corner is (p->width, p->height).
 * \param drvthis  Pointer to driver structure.
 * \param x        Horizontal character position (column).
 * \param y        Vertical character position (row).
 * \param c        Character that gets written.
 */
MODULE_EXPORT void
serialVFD_chr (Driver *drvthis, int x, int y, char c)
{
	PrivateData *p = drvthis->private_data;

	if ((x > p->width) || (y > p->height))
		return;
	y--;
	x--;

	p->framebuf[(y * p->width) + x ] = c;
}


/**
 * Draw a vertical bar bottom-up.
 * \param drvthis  Pointer to driver structure.
 * \param x        Horizontal character position (column) of the starting point.
 * \param y        Vertical character position (row) of the starting point.
 * \param len      Number of characters that the bar is high at 100%
 * \param promille Current height level of the bar in promille.
 * \param options  Options (currently unused).
 */
MODULE_EXPORT void
serialVFD_vbar (Driver *drvthis, int x, int y, int len, int promille, int options)
{
	PrivateData *p = drvthis->private_data;

	if (p->customchars >= p->cellheight || p->predefined_vbar == 1) {
		serialVFD_init_vbar(drvthis);
		lib_vbar_static(drvthis, x, y, len, promille, options, p->cellheight, p->vbar_cc_offset);
	}
	else {
		lib_vbar_static(drvthis, x, y, len, promille, options, 2, 0x5E);
	}
}


/**
 * Draw a horizontal bar to the right.
 * \param drvthis  Pointer to driver structure.
 * \param x        Horizontal character position (column) of the starting point.
 * \param y        Vertical character position (row) of the starting point.
 * \param len      Number of characters that the bar is long at 100%
 * \param promille Current length level of the bar in promille.
 * \param options  Options (currently unused).
 */
MODULE_EXPORT void
serialVFD_hbar (Driver *drvthis, int x, int y, int len, int promille, int options)
{
	PrivateData *p = drvthis->private_data;

	if (p->customchars >= p->cellwidth || p->predefined_hbar == 1) {
		serialVFD_init_hbar(drvthis);
		lib_hbar_static(drvthis, x, y, len, promille, options, p->cellwidth, p->hbar_cc_offset);
	}
	else {
		lib_hbar_static(drvthis, x, y, len, promille, options, 2, 0x2C);
	}
}


/**
 * Write a big number to the screen.
 * \param drvthis  Pointer to driver structure.
 * \param x        Horizontal character position (column).
 * \param num      Character to write (0 - 10 with 10 representing ':')
 */
MODULE_EXPORT void
serialVFD_num(Driver * drvthis, int x, int num)
{
	PrivateData *p = drvthis->private_data;
	int do_init = 0;

	if (p->ccmode != bignum) {
		/* If custom characters are not yet set up Lib_adv_bignum has
		 * to do it. */
		do_init = 1;
		p->ccmode = bignum;
	}
	lib_adv_bignum(drvthis, x, num, 0, do_init);
}


/**
 * Place an icon on the screen.
 * \param drvthis  Pointer to driver structure.
 * \param x        Horizontal character position (column).
 * \param y        Vertical character position (row).
 * \param icon     synbolic value representing the icon.
 * \retval 0       Icon has been successfully defined/written.
 * \retval <0      Server core shall define/write the icon.
 */
MODULE_EXPORT int
serialVFD_icon (Driver *drvthis, int x, int y, int icon)
{
	PrivateData *p = drvthis->private_data;
	static unsigned char heart_open[] =
		{ b__XXXXX,
		  b__X_X_X,
		  b_______,
		  b_______,
		  b_______,
		  b__X___X,
		  b__XX_XX,
		  b__XXXXX };
	static unsigned char heart_filled[] =
		{ b__XXXXX,
		  b__X_X_X,
		  b___X_X_,
		  b___XXX_,
		  b___XXX_,
		  b__X_X_X,
		  b__XX_XX,
		  b__XXXXX };

	switch (icon) {
		case ICON_BLOCK_FILLED:
			serialVFD_chr(drvthis, x, y, 127);
			break;
		case ICON_HEART_FILLED:
			if (p->customchars > 0) {
		        	p->ccmode = standard;
				serialVFD_set_char(drvthis, 0, heart_filled);
				serialVFD_chr(drvthis, x, y, 0);
			}
			else
				serialVFD_icon(drvthis, x, y, ICON_BLOCK_FILLED);
			break;
		case ICON_HEART_OPEN:
			if (p->customchars > 0) {
				p->ccmode = standard;
				serialVFD_set_char(drvthis, 0, heart_open);
				serialVFD_chr(drvthis, x, y, 0);
			}
			else
				serialVFD_chr(drvthis, x, y, 0x23);
			break;
		default:
			return -1;	/* Let the core do other icons */
	}
	return 0;
}


/**
 * Get total number of custom characters available.
 * \param drvthis  Pointer to driver structure.
 * \return         Number of custom characters.
 */
MODULE_EXPORT int
serialVFD_get_free_chars (Driver *drvthis)
{
	PrivateData *p = drvthis->private_data;

	return p->customchars;
}


/**
 * Define a custom character and write it to the VFD.
 *
 * Converts the 5x7 matrix of bits stored in 7 bytes into a VFD specific
 * byte sequence.
 *
 * \param drvthis  Pointer to driver structure.
 * \param n        Custom character to define [0 - (p->customchars)].
 * \param dat      Array of 7(=cellheight) bytes, each representing a pixel row
 *                 starting from the top to bottom.
 *                 The bits in each byte represent the pixels where the LSB
 *                 (least significant bit) is the rightmost pixel in each pixel row.
 */
MODULE_EXPORT void
serialVFD_set_char (Driver *drvthis, int n, unsigned char *dat)
{
	PrivateData *p = drvthis->private_data;
	unsigned int byte, bit;

	if (n < 0 || n > p->customchars-1)
		return;
	if (!dat)
		return;

	for (byte = 0; byte < p->usr_chr_dot_assignment[0]; byte++) {
		int letter = 0;

		for (bit = 0; bit < 8; bit++) {
			/* map bit from 5x7 matrix into current byte/bit */
			int pos = (int) p->usr_chr_dot_assignment[bit+8*byte+1];

			if (pos > 0) {
				int posbyte = (pos-1) / 5;
				int posbit = 4 - ((pos-1) % 5);

				letter |= ((dat[posbyte] >> posbit) & 1) << bit;
			}
		}
		p->custom_char[n][byte] = letter;
	}

}


/**
 * Retrieve brightness.
 * \param drvthis  Pointer to driver structure.
 * \param state    Brightness state (on/off) for which we want the value.
 * \return         Stored brightness in promille.
 */
MODULE_EXPORT int
serialVFD_get_brightness(Driver *drvthis, int state)
{
	PrivateData *p = drvthis->private_data;

	return (state == BACKLIGHT_ON) ? p->on_brightness : p->off_brightness;
}


/**
 * Set on/off brightness.
 * \param drvthis  Pointer to driver structure.
 * \param state    Brightness state (on/off) for which we want to store the value.
 * \param promille New brightness in promille.
 */
MODULE_EXPORT void
serialVFD_set_brightness(Driver *drvthis, int state, int promille)
{
	PrivateData *p = drvthis->private_data;

	/* Check it */
	if (promille < 0 || promille > 1000)
		return;

	/* store the software value since there is not get */
	if (state == BACKLIGHT_ON) {
		p->on_brightness = promille;
	}
	else {
		p->off_brightness = promille;
	}
}


/**
 * Turn display backlight on or off.
 * This does not really toggle the backlight, but  tries to handle it more intelligently:
 * it sets the brightness to the value defined for the related backlight state.
 * \param drvthis  Pointer to driver structure.
 * \param on       New backlight status.
 */
MODULE_EXPORT void
serialVFD_backlight (Driver *drvthis, int on)
{
	PrivateData *p = drvthis->private_data;
	int hardware_value = (on == BACKLIGHT_ON)
			     ? p->on_brightness
			     : p->off_brightness;

	/*
	 * map range [0, 1000] -> [0, 4] that the hardware understands
	 * (4 steps 0-250, 251-500, 501-750, 751-1000)
	 */
	hardware_value /= 251;
	if (hardware_value != p->hw_brightness) {
		p->hw_brightness = hardware_value;
		Port_Function[p->use_parallel].write_fkt(drvthis, &p->hw_cmd[p->hw_brightness][1],\
		p->hw_cmd[p->hw_brightness][0]);
	}
}


/**
 * Provide general information about the LCD/VFD display/driver.
 * \param drvthis  Pointer to driver structure.
 * \return         Constant string with information.
 */
MODULE_EXPORT const char *
serialVFD_get_info (Driver *drvthis)
{
	PrivateData *p = drvthis->private_data;

	strcpy(p->info, "Driver for many serialVFDs from NEC(all FIPC based), Noritake, Futaba and the \"KD Rev2.1\"VFD");
	return p->info;
}


/**
 * Set up vertical bars.
 * \param drvthis  Pointer to driver structure.
 *
 * \todo
 * Called only by vbar(). Can possibly be included there.
 * This should also make CCMODE independent of the implementation of the bars.
 */
static void
serialVFD_init_vbar (Driver *drvthis)
{
	PrivateData *p = drvthis->private_data;

	if (p->ccmode != vbar) {
		unsigned char vBar[p->cellheight];
		int i;

		p->ccmode = vbar;

		memset(vBar, 0x00, sizeof(vBar));

		for (i = 1; i < p->cellheight; i++) {
			/* add pixel line per pixel line ... */
			vBar[p->cellheight - i] = 0xFF;
			serialVFD_set_char(drvthis, i, vBar);
		}
	}
}


/**
 * Set up horizontal bars.
 * \param drvthis  Pointer to driver structure.
 *
 * \todo
 * Called only by hbar(). Can possibly be included there.
 * This should also make CCMODE independent of the implementation of the bars.
 */
static void
serialVFD_init_hbar (Driver *drvthis)
{
	PrivateData *p = drvthis->private_data;

	if (p->ccmode != hbar) {
		unsigned char hBar[p->cellheight];
		int i;

		p->ccmode = hbar;

		for (i = 1; i < p->cellwidth; i++) {
			/* fill pixel columns from left to right. */
			memset(hBar, 0xFF & ~((1 << (p->cellwidth - i)) - 1), sizeof(hBar));
			serialVFD_set_char(drvthis, i, hBar);
		}
	}
}


/**
 * Put a custom character in the display's RAM. The character definition is
 * read from custom_char cache.
 * \param  drvthis  Pointer to driver
 * \param  n        Index of the custom character in cache
 */
static void
serialVFD_put_char (Driver *drvthis, int n)
{
	PrivateData *p = drvthis->private_data;

	Port_Function[p->use_parallel].write_fkt(drvthis, &p->hw_cmd[set_user_char][1],\
		p->hw_cmd[set_user_char][0]);
	Port_Function[p->use_parallel].write_fkt(drvthis, (unsigned char *) &p->usr_chr_load_mapping[n], 1);
	Port_Function[p->use_parallel].write_fkt(drvthis, &p->custom_char[n][0], p->usr_chr_dot_assignment[0]);// overwrite selected Character
}


/**
 * Finally write character/usercharacter on the display.
 * Written characters in area 128...255 are mapped according to charmap if
 * ISO_8859_1 is enabled.
 * \param  drvthis  Pointer to driver
 * \param  i        Index of character in framebuffer to write
 *
 */
static void
serialVFD_hw_write (Driver *drvthis, int i)
{
	PrivateData *p = drvthis->private_data;

	if (p->framebuf[i] <= 30) {	/* custom character */
		if (p->display_type == 1) {	/* KD Rev 2.1 only */
			if (p->last_custom != p->framebuf[i]) {
				/* substitute and select character to overwrite (237) */
				Port_Function[p->use_parallel].write_fkt(drvthis, (unsigned char *)"\x1A\xDB", 2);
				/* overwrite selected character */
				Port_Function[p->use_parallel].write_fkt(drvthis, &p->custom_char[(int)p->framebuf[i]][0], 7);
			}
			/* write character */
			Port_Function[p->use_parallel].write_fkt(drvthis, (unsigned char *)"\xDB", 1);
			p->last_custom = p->framebuf[i];
		}
		else {		/* all other displays */
			Port_Function[p->use_parallel].write_fkt(drvthis, (unsigned char *) &p->usr_chr_mapping[(int)p->framebuf[i]], 1);
		}
	}
	else if ((p->framebuf[i] == 127) || ((p->framebuf[i] > 127) && (p->ISO_8859_1 != 0))) {
		/* ISO_8859_1 translation for 129 ... 255 */
		Port_Function[p->use_parallel].write_fkt(drvthis, &p->charmap[p->framebuf[i] - 127], 1);
	}
	else {
		Port_Function[p->use_parallel].write_fkt(drvthis, &p->framebuf[i], 1);
	}
}