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Use C-comment style (practise what I preach).

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This commit is contained in:
mmdolze
2010-11-16 21:48:34 +00:00
parent 6deaa40e83
commit 67c07b52dd
1 changed files with 143 additions and 112 deletions
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server/drivers/hd44780.c
+143 -112
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@@ -14,7 +14,8 @@
* \li Modify the makefile
*/
/* Modular driver created and generic support for multiple displays added
/*-
* Modular driver created and generic support for multiple displays added
* Dec 1999, Benjamin Tse <blt@Comports.com>
*
* Modified July 2000 by Charles Steinkuehler to use one of 3 methods for delay
@@ -50,20 +51,22 @@
*/
// Uncomment one of the lines below to select your desired delay generation
// mechanism. If both defines are commented, the original I/O read timing
// loop is used. Using DELAY_NANOSLEEP seems to provide the best performance.
/*
* Uncomment one of the lines below to select your desired delay generation
* mechanism. If both defines are commented, the original I/O read timing
* loop is used. Using DELAY_NANOSLEEP seems to provide the best performance.
*/
//#define DELAY_GETTIMEOFDAY
#define DELAY_NANOSLEEP
//#define DELAY_IOCALLS
// Default parallel port address
/* Default parallel port address */
#define LPTPORT 0x378
// Default Lineaddress in ext_mode
/* Default Lineaddress in ext_mode */
#define LADDR 0x20
// Autorepeat values
/* Autorepeat values */
#define KEYPAD_AUTOREPEAT_DELAY 500
#define KEYPAD_AUTOREPEAT_FREQ 15
@@ -91,7 +94,7 @@
#include "hd44780-drivers.h"
#include "hd44780-charmap.h"
// Only one alternate delay method at a time, please ;-)
/* Only one alternate delay method at a time, please ;-) */
#if defined DELAY_GETTIMEOFDAY
# undef DELAY_NANOSLEEP
#elif defined DELAY_NANOSLEEP
@@ -119,7 +122,9 @@ static char *defaultKeyMapMatrix[KEYPAD_MAXY][KEYPAD_MAXX] = {
/* Vars for the server core */
MODULE_EXPORT char * api_version = API_VERSION;
MODULE_EXPORT int stay_in_foreground = 0;
MODULE_EXPORT int supports_multiple = 1; // yes, we have no global variables (except for constants)
MODULE_EXPORT int supports_multiple = 1; /* yes, we have no global
* variables (except for
* constants) */
MODULE_EXPORT char *symbol_prefix = "HD44780_";
@@ -141,33 +146,34 @@ static int parse_span_list(int *spanListArray[], int *spLsize, int *dispOffsets[
MODULE_EXPORT int
HD44780_init(Driver *drvthis)
{
// TODO: remove the two magic numbers below
// TODO: single point of return
/* TODO: single point of return */
char buf[40];
const char *s;
int i = 0;
int (*init_fn)(Driver *drvthis) = NULL;
int (*init_fn) (Driver *drvthis) = NULL;
int if_type = IF_TYPE_UNKNOWN;
int tmp;
PrivateData *p;
char conf_charmap[MAX_CHARMAP_NAME_LENGTH];
// Alocate and store private data
/* Alocate 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 private data
p->cellheight = 8; /* Do not change this !!! This is a controller property, not a display property !!! */
/* initialize private data */
p->cellheight = 8; /* Do not change this !!! This is a
* controller property, not a display
* property !!! */
p->cellwidth = 5;
p->ccmode = standard;
p->backlightstate = -1; // Init to invalid value
p->backlightstate = -1; /* Init to invalid value */
p->fd = -1;
//// READ THE CONFIG FILE
/* READ THE CONFIG FILE */
p->port = drvthis->config_get_int(drvthis->name, "port", 0, LPTPORT);
p->ext_mode = drvthis->config_get_bool(drvthis->name, "extendedmode", 0, 0);
@@ -184,25 +190,25 @@ HD44780_init(Driver *drvthis)
p->nextkeepalive = 0;
p->keepalivedisplay = drvthis->config_get_int(drvthis->name, "keepalivedisplay", 0, 0);
// Get and search for the connection type
/* Get and search for the connection type */
s = drvthis->config_get_string(drvthis->name, "ConnectionType", 0, "4bit");
for (i = 0; (connectionMapping[i].name != NULL) &&
(strcasecmp(s, connectionMapping[i].name) != 0); i++)
;
if (connectionMapping[i].name == NULL) {
report(RPT_ERR, "%s: unknown ConnectionType: %s", drvthis->name, s);
return -1; // fatal error
return -1;
} else {
/* set connection type */
p->connectiontype = connectionMapping[i].connectiontype;
report(RPT_INFO,"HD44780: using ConnectionType: %s", connectionMapping[i].name);
report(RPT_INFO, "HD44780: using ConnectionType: %s", connectionMapping[i].name);
if_type = connectionMapping[i].if_type;
init_fn = connectionMapping[i].init_fn;
}
// Get and parse vspan only when specified
/* Get and parse vspan only when specified */
s = drvthis->config_get_string(drvthis->name, "vspan", 0, "");
if (s[0] != '\0') {
if (parse_span_list(&(p->spanList), &(p->numLines), &(p->dispVOffset), &(p->numDisplays), &(p->dispSizes), s) == -1) {
@@ -211,11 +217,11 @@ HD44780_init(Driver *drvthis)
}
}
// Get and parse size
/* Get and parse size */
s = drvthis->config_get_string(drvthis->name, "size", 0, "20x4");
if (sscanf(s, "%dx%d", &(p->width), &(p->height)) != 2
|| (p->width <= 0) || (p->width > LCD_MAX_WIDTH)
|| (p->height <= 0) || (p->height > LCD_MAX_HEIGHT)) {
|| (p->width <= 0) || (p->width > LCD_MAX_WIDTH)
|| (p->height <= 0) || (p->height > LCD_MAX_HEIGHT)) {
report(RPT_ERR, "%s: cannot read Size %s", drvthis->name, s);
}
@@ -246,7 +252,7 @@ HD44780_init(Driver *drvthis)
}
p->offbrightness = tmp;
// default case for when spans aren't indicated
/* default case for when spans aren't indicated */
if (p->numLines == 0) {
if ((p->spanList = (int *) calloc(sizeof(int), p->height)) != NULL) {
int i;
@@ -258,7 +264,7 @@ HD44780_init(Driver *drvthis)
report(RPT_ERR, "%s: error allocing", drvthis->name);
}
else {
// sanity check against p->height
/* sanity check against p->height */
if (p->numLines != p->height)
report(RPT_ERR, "%s: height in Size does not match vSpan", drvthis->name);
}
@@ -279,9 +285,9 @@ HD44780_init(Driver *drvthis)
}
#if defined DELAY_NANOSLEEP
// Change to Round-Robin scheduling for nanosleep
/* Change to Round-Robin scheduling for nanosleep */
{
// Set priority to 1
/* Set priority to 1 */
struct sched_param param;
param.sched_priority = 1;
if ((sched_setscheduler(0, SCHED_RR, &param)) == -1) {
@@ -292,7 +298,7 @@ HD44780_init(Driver *drvthis)
}
#endif
// Allocate framebuffer
/* Allocate framebuffer */
p->framebuf = (unsigned char *) calloc(p->width * p->height, sizeof(char));
if (p->framebuf == NULL) {
report(RPT_ERR, "%s: unable to allocate framebuffer", drvthis->name);
@@ -300,29 +306,29 @@ HD44780_init(Driver *drvthis)
return -1;
}
// Allocate and clear the buffer for incremental updates
/* Allocate and clear the buffer for incremental updates */
p->backingstore = (unsigned char *) calloc(p->width * p->height, sizeof(char));
if (p->backingstore == NULL) {
report(RPT_ERR, "%s: unable to allocate framebuffer backing store", drvthis->name);
return -1;
}
// Keypad ?
/* Keypad ? */
if (p->have_keypad) {
int x, y;
// Read keymap
/* Read keymap */
for (x = 0; x < KEYPAD_MAXX; x++) {
char buf[40];
// First fill with default value
/* First fill with default value */
p->keyMapDirect[x] = defaultKeyMapDirect[x];
// Read config value
/* Read config value */
sprintf(buf, "keydirect_%1d", x+1);
s = drvthis->config_get_string(drvthis->name, buf, 0, NULL);
// Was a key specified in the config file ?
/* Was a key specified in the config file ? */
if (s) {
p->keyMapDirect[x] = strdup(s);
report(RPT_INFO, "HD44780: Direct key %d: \"%s\"", x, s);
@@ -333,14 +339,14 @@ HD44780_init(Driver *drvthis)
for (y = 0; y < KEYPAD_MAXY; y++) {
char buf[40];
// First fill with default value
/* First fill with default value */
p->keyMapMatrix[y][x] = defaultKeyMapMatrix[y][x];
// Read config value
/* Read config value */
sprintf(buf, "keymatrix_%1d_%d", x+1, y+1);
s = drvthis->config_get_string(drvthis->name, buf, 0, NULL);
// Was a key specified in the config file ?
/* Was a key specified in the config file ? */
if (s) {
p->keyMapMatrix[y][x] = strdup(s);
report(RPT_INFO, "HD44780: Matrix key %d %d: \"%s\"", x, y, s);
@@ -349,7 +355,7 @@ HD44780_init(Driver *drvthis)
}
}
// Get configured charmap
/* Get configured charmap */
strncpy(conf_charmap, drvthis->config_get_string(drvthis->name, "charmap", 0, "hd44780_default"), MAX_CHARMAP_NAME_LENGTH);
conf_charmap[MAX_CHARMAP_NAME_LENGTH-1] = '\0';
p->charmap = 0;
@@ -369,15 +375,18 @@ HD44780_init(Driver *drvthis)
}
report(RPT_INFO, "%s: Using %s charmap", drvthis->name, available_charmaps[p->charmap].name);
// Output latch state - init to a non-valid value
/* Output latch state - init to a non-valid value */
p->output_state = 999999;
// allocate local function pointers
/* allocate local function pointers */
if ((p->hd44780_functions = (HD44780_functions *) calloc(1, sizeof(HD44780_functions))) == NULL) {
report(RPT_ERR, "%s: error mallocing", drvthis->name);
return -1;
}
// pre-set local function pointers (may be overridden by local init function)
/*
* pre-set local function pointers (may be overridden by local init
* function)
*/
p->hd44780_functions->uPause = uPause;
p->hd44780_functions->drv_report = report;
p->hd44780_functions->drv_debug = debug;
@@ -390,39 +399,39 @@ HD44780_init(Driver *drvthis)
p->hd44780_functions->close = NULL;
p->hd44780_functions->flush = NULL;
// Do local (=connection type specific) display init
/* Do local (=connection type specific) display init */
if (init_fn(drvthis) != 0)
return -1;
// consistency check: fail if local senddata function was not defined
/* consistency check: fail if local senddata function was not defined */
if (p->hd44780_functions->senddata == NULL) {
report(RPT_ERR, "%s: incomplete functions for connection type",
drvthis->name);
return -1;
}
// set scankeypad function if local readkeypad function is defined
/* set scankeypad function if local readkeypad function is defined */
if ((p->hd44780_functions->readkeypad != NULL) &&
(p->hd44780_functions->scankeypad == NULL)) {
p->hd44780_functions->scankeypad = HD44780_scankeypad;
}
// consistency check: no local keypad function => no keypad
/* consistency check: no local keypad function => no keypad */
if (p->hd44780_functions->scankeypad == NULL)
p->have_keypad = 0;
// consistency check: no local backlight function => no backlight
/* consistency check: no local backlight function => no backlight */
if (p->hd44780_functions->backlight == NULL)
p->have_backlight = 0;
// consistency check: no local output function => no output
/* consistency check: no local output function => no output */
if (p->hd44780_functions->output == NULL)
p->have_output = 0;
// set contrast
/* set contrast */
HD44780_set_contrast(drvthis, p->contrast);
// Display startup parameters on the LCD
/* Display startup parameters on the LCD */
HD44780_clear(drvthis);
sprintf(buf, "HD44780 %dx%d", p->width, p->height);
HD44780_string(drvthis, 1, 1, buf);
@@ -485,7 +494,7 @@ void
common_init(PrivateData *p, unsigned char if_bit)
{
if (p->ext_mode) {
// Set up extended mode
/* Set up extended mode */
p->hd44780_functions->senddata(p, 0, RS_INSTR, FUNCSET | if_bit | TWOLINE | SMALLCHAR | EXTREG);
p->hd44780_functions->uPause(p, 40);
p->hd44780_functions->senddata(p, 0, RS_INSTR, EXTMODESET | FOURLINE);
@@ -528,8 +537,8 @@ HD44780_close(Driver *drvthis)
PrivateData *p = (PrivateData *) drvthis->private_data;
if (p != NULL) {
if (p->hd44780_functions->close != NULL)
p->hd44780_functions->close(p);
if (p->hd44780_functions->close != NULL)
p->hd44780_functions->close(p);
if (p->framebuf)
free(p->framebuf);
@@ -614,10 +623,13 @@ HD44780_position(Driver *drvthis, int x, int y)
int DDaddr;
if (p->ext_mode) {
// Linear addressing, each line starts 0x20 higher.
/* Linear addressing, each line starts 0x20 higher. */
DDaddr = x + relY * p->line_address;
} else {
// 16x1 is a special case
/*
* 16x1 is a special case: char 0 starts at 0x00, but char 8
* starts at 0x40.
*/
if (p->dispSizes[dispID - 1] == 1 && p->width == 16) {
if (x >= 8) {
x -= 8;
@@ -625,12 +637,16 @@ HD44780_position(Driver *drvthis, int x, int y)
}
}
/*
* Line 1 starts at 0x00, line 2 start at 0x40, line 3
* continues from line 1 and line 4 continues from line 2.
*/
DDaddr = x + (relY % 2) * 0x40;
if ((relY % 4) >= 2)
DDaddr += p->width;
}
p->hd44780_functions->senddata(p, dispID, RS_INSTR, POSITION | DDaddr);
p->hd44780_functions->uPause(p, 40); // Minimum exec time for all commands
p->hd44780_functions->uPause(p, 40); /* Minimum exec time for all commands */
if (p->hd44780_functions->flush != NULL)
p->hd44780_functions->flush(p);
}
@@ -652,19 +668,19 @@ HD44780_flush(Driver *drvthis)
char keepaliveNow = 0;
time_t now = time(NULL);
// force full refresh of display
/* force full refresh of display */
if ((p->refreshdisplay > 0) && (now > p->nextrefresh)) {
refreshNow = 1;
p->nextrefresh = now + p->refreshdisplay;
}
// keepalive refresh of display
/* keepalive refresh of display */
if ((p->keepalivedisplay > 0) && (now > p->nextkeepalive)) {
keepaliveNow = 1;
p->nextkeepalive = now + p->keepalivedisplay;
}
// Update LCD incrementally by comparing with last contents
/* Update LCD incrementally by comparing with last contents */
count = 0;
for (y = 0; y < p->height; y++) {
int drawing = 0;
@@ -673,16 +689,16 @@ HD44780_flush(Driver *drvthis)
unsigned char ch = p->framebuf[(y * wid) + x];
if (refreshNow || (x + y == 0 && keepaliveNow) || ch != p->backingstore[(y*wid)+x]) {
if (!drawing || x % 8 == 0) { // x%8 is for 16x1 displays !
if (!drawing || x % 8 == 0) { /* x%8 is for 16x1 displays ! */
drawing = 1;
HD44780_position(drvthis,x,y);
}
p->hd44780_functions->senddata(p, p->spanList[y], RS_DATA,
available_charmaps[p->charmap].charmap[ch]);
p->hd44780_functions->uPause(p, 40); // Minimum exec time for all commands
p->hd44780_functions->uPause(p, 40); /* Minimum exec time for all commands */
p->backingstore[(y*wid)+x] = ch;
count++;
}
}
else {
drawing = 0;
}
@@ -698,7 +714,7 @@ HD44780_flush(Driver *drvthis)
/* Tell the HD44780 we will redefine char number i */
p->hd44780_functions->senddata(p, 0, RS_INSTR, SETCHAR | i * 8);
p->hd44780_functions->uPause(p, 40); // Minimum exec time for all commands
p->hd44780_functions->uPause(p, 40); /* Minimum exec time for all commands */
/* Send the subsequent rows */
for (row = 0; row < p->cellheight; row++) {
@@ -764,14 +780,14 @@ HD44780_string(Driver *drvthis, int x, int y, const char string[])
PrivateData *p = (PrivateData *) drvthis->private_data;
int i;
x--; // Convert 1-based coords to 0-based
x--; /* Convert 1-based coords to 0-based */
y--;
if ((y < 0) || (y >= p->height))
return;
for (i = 0; (string[i] != '\0') && (x < p->width); i++, x++) {
if (x >= 0) // no write left of left border
if (x >= 0) /* no write left of left border */
p->framebuf[(y * p->width) + x] = string[i];
}
}
@@ -858,7 +874,10 @@ HD44780_set_brightness(Driver *drvthis, int state, int promille)
p->offbrightness = promille;
}
// Make last backlight state invalid to force update on next rendering
/*
* Make last backlight state invalid to force update on next
* rendering
*/
p->backlightstate = -1;
}
@@ -873,7 +892,7 @@ HD44780_backlight(Driver *drvthis, int on)
{
PrivateData *p = (PrivateData *) drvthis->private_data;
// Immediately return if no backlight is available or no change is necessary
/* Immediately return if no backlight is available or no change is necessary */
if (!p->have_backlight || p->backlightstate == on)
return;
@@ -898,11 +917,13 @@ HD44780_vbar(Driver *drvthis, int x, int y, int len, int promille, int options)
{
PrivateData *p = (PrivateData *) drvthis->private_data;
/* x and y are the start position of the bar.
/*
* x and y are the start position of the bar.
* The bar by default grows in the 'up' direction
* (other direction not yet implemented).
* len is the number of characters that the bar is long at 100%
* promille is the number of promilles (0..1000) that the bar should be filled.
* promille is the number of promilles (0..1000) that the bar should
* be filled.
*/
if (p->ccmode != vbar) {
@@ -920,7 +941,7 @@ HD44780_vbar(Driver *drvthis, int x, int y, int len, int promille, int options)
memset(vBar, 0x00, sizeof(vBar));
for (i = 1; i < p->cellheight; i++) {
// add pixel line per pixel line ...
/* add pixel line per pixel line ... */
vBar[p->cellheight - i] = 0xFF;
HD44780_set_char(drvthis, i, vBar);
}
@@ -944,7 +965,8 @@ HD44780_hbar(Driver *drvthis, int x, int y, int len, int promille, int options)
{
PrivateData *p = (PrivateData *) drvthis->private_data;
/* x and y are the start position of the bar.
/*
* x and y are the start position of the bar.
* The bar by default grows in the 'right' direction
* (other direction not yet implemented).
* len is the number of characters that the bar is long at 100%
@@ -965,7 +987,7 @@ HD44780_hbar(Driver *drvthis, int x, int y, int len, int promille, int options)
p->ccmode = hbar;
for (i = 1; i <= p->cellwidth; i++) {
// fill pixel columns from left to right.
/* fill pixel columns from left to right. */
memset(hBar, 0xFF & ~((1 << (p->cellwidth - i)) - 1), sizeof(hBar));
HD44780_set_char(drvthis, i, hBar);
}
@@ -987,7 +1009,7 @@ HD44780_num(Driver *drvthis, int x, int num)
PrivateData *p = (PrivateData *) drvthis->private_data;
int do_init = 0;
if ((num < 0) || (num > 10))
if ((num < 0) || (num > 10))
return;
if (p->ccmode != bignum) {
@@ -1003,7 +1025,7 @@ HD44780_num(Driver *drvthis, int x, int num)
do_init = 1;
}
// Lib_adv_bignum does everything needed to show the bignumbers.
/* Lib_adv_bignum does everything needed to show the bignumbers. */
lib_adv_bignum(drvthis, x, num, 0, do_init);
}
@@ -1016,9 +1038,7 @@ HD44780_num(Driver *drvthis, int x, int num)
MODULE_EXPORT int
HD44780_get_free_chars(Driver *drvthis)
{
//PrivateData *p = drvthis->private_data;
return NUM_CCs;
return NUM_CCs;
}
@@ -1104,7 +1124,7 @@ HD44780_icon(Driver *drvthis, int x, int y, int icon)
b___XXX_,
b____X__,
b_______ };
/*
/*-
static unsigned char arrow_left[] =
{ b_______,
b____X__,
@@ -1151,7 +1171,7 @@ HD44780_icon(Driver *drvthis, int x, int y, int icon)
b__X_X_X,
b__XXXXX,
b_______ };
/*
/*-
static unsigned char selector_left[] =
{ b___X___,
b___XX__,
@@ -1231,7 +1251,7 @@ HD44780_icon(Driver *drvthis, int x, int y, int icon)
HD44780_chr(drvthis, x, y, 5);
break;
default:
return -1; /* Let the core do other icons */
return -1; /* Let the core do other icons */
}
return 0;
}
@@ -1251,7 +1271,7 @@ HD44780_get_key(Driver *drvthis)
char *keystr = NULL;
struct timeval curr_time, time_diff;
// return "no key pressed" if required functions mission or input disabled
/* return "no key pressed" if required functions mission or input disabled */
if ((!p->have_keypad) || (p->hd44780_functions->scankeypad == NULL))
return NULL;
@@ -1259,7 +1279,7 @@ HD44780_get_key(Driver *drvthis)
scancode = p->hd44780_functions->scankeypad(p);
if (scancode != '\0') {
// Check if arrays are large enough
/* Check if arrays are large enough */
if ((scancode&0x0F) > KEYPAD_MAXX || ((scancode&0xF0)>>4) > KEYPAD_MAXY) {
report(RPT_WARNING, "HD44780_get_key: Scancode out of range: %d",
scancode);
@@ -1275,15 +1295,18 @@ HD44780_get_key(Driver *drvthis)
if (keystr == p->pressed_key) {
timersub(&curr_time, &(p->pressed_key_time), &time_diff);
if (((time_diff.tv_usec / 1000 + time_diff.tv_sec * 1000) - KEYPAD_AUTOREPEAT_DELAY) < 1000 * p->pressed_key_repetitions / KEYPAD_AUTOREPEAT_FREQ) {
// The key is already pressed quite some time
// but it's not yet time to return a repeated keypress
/*
* The key is already pressed quite some time
* but it's not yet time to return a repeated
* keypress
*/
return NULL;
}
// Otherwise a keypress will be returned
/* Otherwise a keypress will be returned */
p->pressed_key_repetitions++;
}
else {
// It's a new keypress
/* It's a new keypress */
p->pressed_key_time = curr_time;
p->pressed_key_repetitions = 0;
report(RPT_INFO, "HD44780_get_key: Key pressed: %s (%d,%d)",
@@ -1291,7 +1314,7 @@ HD44780_get_key(Driver *drvthis)
}
}
// Store the key for the next round
/* Store the key for the next round */
p->pressed_key = keystr;
return keystr;
@@ -1327,41 +1350,45 @@ unsigned char HD44780_scankeypad(PrivateData *p)
unsigned char scancode = 0;
// return 'no key pressed' if no keypad reading function defined
/* return 'no key pressed' if no keypad reading function defined */
if (p->hd44780_functions->readkeypad == NULL)
return('\0');
// Step 1: Check if a directly connected key is pressed
// Put all zeros on Y of keypad
/* Step 1: Check if a directly connected key is pressed */
/* Put all zeros on Y of keypad */
keybits = p->hd44780_functions->readkeypad(p, 0);
if (keybits) {
// A directly connected key was pressed
// Which key was it ?
/*
* A directly connected key was pressed
* Which key was it ?
*/
shiftingbit = 1;
for (shiftcount = 0; shiftcount < KEYPAD_MAXX && !scancode; shiftcount++) {
if (keybits & shiftingbit) {
// Found !
/* Found ! */
scancode = shiftcount+1;
}
shiftingbit <<= 1;
}
}
else {
// Now check the matrix
// Step 2: Check with all 1's to see if a key is pressed at all
/* Now check the matrix */
/* Step 2: Check with all 1's to see if a key is pressed at all */
Ypattern = (1 << KEYPAD_MAXY) - 1;
if (p->hd44780_functions->readkeypad(p, Ypattern)) {
// Yes, a key on the matrix is pressed
// Step 3: Determine the row
// Do a 'binary search' to minimize I/O
// Requires 4 I/O reads
/*
* Yes, a key on the matrix is pressed
*
* Step 3: Determine the row
* Do a 'binary search' to minimize I/O
* Requires 4 I/O reads
*/
Ypattern = 0;
Yval = 0;
for (exp=3; exp>=0; exp--) {
Ypattern = ((1 << (1 << exp)) - 1) << Yval;
/*
/*-
* The above line generates the line mask for
* the binary search. Example if a key is
* pressed on row 3:
@@ -1377,13 +1404,13 @@ unsigned char HD44780_scankeypad(PrivateData *p)
}
}
// Step 4: Final read
/* Step 4: Final read */
keybits = p->hd44780_functions->readkeypad(p, 1<<Yval);
// Step 5: Which key is pressed in that row ?
/* Step 5: Which key is pressed in that row ? */
shiftingbit = 1;
for (shiftcount = 0; shiftcount < KEYPAD_MAXX && !scancode; shiftcount++) {
if (keybits & shiftingbit) {
// Found !
/* Found ! */
scancode = (Yval+1) << 4 | (shiftcount+1);
}
shiftingbit <<= 1;
@@ -1404,19 +1431,21 @@ HD44780_output(Driver *drvthis, int on)
{
PrivateData *p = drvthis->private_data;
// return immediately if output is disabled
/* return immediately if output is disabled */
if (!p->have_output)
return;
// perhaps it is better just to do this every time in case of a glitch
// but leaving this in does make sure that any latch-enable line glitches
// are more easily seen
/*
* perhaps it is better just to do this every time in case of a glitch
* but leaving this in does make sure that any latch-enable line glitches
* are more easily seen.
*/
if (p->output_state == on)
return;
p->output_state = on;
// call output function only if it is defined for the commenction type
/* call output function only if it is defined for the commenction type */
if (p->hd44780_functions->output != NULL)
p->hd44780_functions->output(p, on);
}
@@ -1444,8 +1473,10 @@ parse_span_list(int *spanListArray[], int *spLsize, int *dispOffsets[], int *dOf
if (spanlist[j] >= '1' && spanlist[j] <= '9') {
int spansize = spanlist[j] - '0';
// add spansize lines to the span list, note the offset to
// the previous display and the size of the display
/*
* add spansize lines to the span list, note the offset
* to the previous display and the size of the display
*/
if ((*spanListArray = (int *) realloc(*spanListArray, sizeof(int) * (*spLsize + spansize)))
&& (*dispOffsets = (int *) realloc(*dispOffsets, sizeof(int) * (*dOffsize + 1)))
&& (*dispSizeArray = (int *) realloc(*dispSizeArray, sizeof(int) * (*dOffsize + 1)))) {
@@ -1459,7 +1490,7 @@ parse_span_list(int *spanListArray[], int *spLsize, int *dispOffsets[], int *dOf
++(*dOffsize);
retVal = *dOffsize;
// find the next number (\0 is also outside this range)
/* find the next number (\0 is also outside this range) */
for (++j; spanlist[j] < '1' || spanlist[j] > '9'; ++j);
} else {
retVal = -1;