Added HD44780 delay options.

LCDd.conf

@@ -119,6 +119,16 @@ Size=20x4
 # If you want to use more than 3 HD44780 controllers on the LPT, you need to 
 # specify this. See documentation.
 
+#DelayMult=2
+# If your display is slow and cannot keep up with the flow of data from
+# LCDd, garbage can appear on the LCDd. Set this delay factor to 2 or 4
+# to increase the delays. Default: 1.
+
+DelayBus=true
+# You can reduce the inserted dalays by setting this to false.
+# On fast PCs it is possible your LCD does not respond correctly.
+# Default: true.
+
 
 [LB216]
 # LB216 driver

server/drivers/hd44780-4bit.c

@@ -118,10 +118,12 @@ hd_init_4bit (HD44780_functions * hd44780_functions, lcd_logical_driver * driver
 		port_out (lptPort + 2, 0 ^ OUTMASK);
 	}
 
+	port_out (lptPort, 0x03);
+	if( delayBus ) hd44780_functions->uPause (1);
 	port_out (lptPort, enableLines | 0x03);
 	if (extIF)
 		port_out (lptPort + 2, ALLEXT ^ OUTMASK);
-	hd44780_functions->uPause (1);
+	if( delayBus ) hd44780_functions->uPause (1);
 	port_out (lptPort, 0x03);
 	if (extIF)
 		port_out (lptPort + 2, 0 ^ OUTMASK);
@@ -130,7 +132,7 @@ hd_init_4bit (HD44780_functions * hd44780_functions, lcd_logical_driver * driver
 	port_out (lptPort, enableLines | 0x03);
 	if (extIF)
 		port_out (lptPort + 2, ALLEXT ^ OUTMASK);
-	hd44780_functions->uPause (1);
+	if( delayBus ) hd44780_functions->uPause (1);
 	port_out (lptPort, 0x03);
 	if (extIF)
 		port_out (lptPort + 2, 0 ^ OUTMASK);
@@ -139,7 +141,7 @@ hd_init_4bit (HD44780_functions * hd44780_functions, lcd_logical_driver * driver
 	port_out (lptPort, enableLines | 0x03);
 	if (extIF)
 		port_out (lptPort + 2, ALLEXT ^ OUTMASK);
-	hd44780_functions->uPause (1);
+	if( delayBus ) hd44780_functions->uPause (1);
 	port_out (lptPort, 0x03);
 	if (extIF)
 		port_out (lptPort + 2, 0 ^ OUTMASK);
@@ -149,7 +151,7 @@ hd_init_4bit (HD44780_functions * hd44780_functions, lcd_logical_driver * driver
 	port_out (lptPort, enableLines | 0x02);
 	if (extIF)
 		port_out (lptPort + 2, ALLEXT ^ OUTMASK);
-	hd44780_functions->uPause (1);
+	if( delayBus ) hd44780_functions->uPause (1);
 	port_out (lptPort, 0x02);
 	if (extIF)
 		port_out (lptPort + 2, 0 ^ OUTMASK);
@@ -187,13 +189,15 @@ lcdstat_HD44780_senddata (unsigned char displayID, unsigned char flags, unsigned
 			enableLines = EnMask[displayID - 1];
 
 		port_out (lptPort, portControl | h);
-		hd44780_functions->uPause (2);
+		if( delayBus ) hd44780_functions->uPause (1);
 		port_out (lptPort, enableLines | portControl | h);
-		hd44780_functions->uPause (4);
+		if( delayBus ) hd44780_functions->uPause (1);
 		port_out (lptPort, portControl | h);
 
+		port_out (lptPort, portControl | l);
+		if( delayBus ) hd44780_functions->uPause (1);
 		port_out (lptPort, enableLines | portControl | l);
-		hd44780_functions->uPause (4);
+		if( delayBus ) hd44780_functions->uPause (1);
 		port_out (lptPort, portControl | l);
 	}
 
@@ -204,14 +208,15 @@ lcdstat_HD44780_senddata (unsigned char displayID, unsigned char flags, unsigned
 			enableLines = EnMask[(displayID - 1)];
 
 		port_out (lptPort, portControl | h);
-		hd44780_functions->uPause (2);
+		if( delayBus ) hd44780_functions->uPause (1);
 		port_out (lptPort + 2, enableLines ^ OUTMASK);
-		hd44780_functions->uPause (4);
+		if( delayBus ) hd44780_functions->uPause (1);
 		port_out (lptPort + 2, 0 ^ OUTMASK);
 
 		port_out (lptPort, portControl | l);
+		if( delayBus ) hd44780_functions->uPause (1);
 		port_out (lptPort + 2, enableLines ^ OUTMASK);
-		hd44780_functions->uPause (4);
+		if( delayBus ) hd44780_functions->uPause (1);
 		port_out (lptPort + 2, 0 ^ OUTMASK);
 	}
 }
@@ -233,6 +238,7 @@ unsigned char lcdstat_HD44780_readkeypad (unsigned int YData)
 	if (!extIF) {
 		port_out (lptPort + 2, ( ((~YData & 0x03C0) << 6 )) ^ OUTMASK);
 	}
+	if( delayBus ) hd44780_functions->uPause (1);
 
 	// Read inputs
 	readval = ~ port_in (lptPort + 1) ^ INMASK;

server/drivers/hd44780-ext8bit.c

@@ -133,8 +133,9 @@ lcdtime_HD44780_senddata (unsigned char displayID, unsigned char flags, unsigned
 	sem_wait (semid);
 	port_out (lptPort + 2, portControl ^ OUTMASK);
 	port_out (lptPort, ch);
+	if( delayBus ) hd44780_functions->uPause (1);
 	port_out (lptPort + 2, (enableLines|portControl) ^ OUTMASK);
-	hd44780_functions->uPause (1);
+	if( delayBus ) hd44780_functions->uPause (1);
 	port_out (lptPort + 2, portControl ^ OUTMASK);
 	sem_signal (semid);
 }
@@ -160,6 +161,7 @@ unsigned char lcdtime_HD44780_readkeypad (unsigned int YData)
 	if (!extIF) {
 		port_out (lptPort + 2, ( ((~YData & 0x0100) >> 8) | ((~YData & 0x0200) >> 6)) ^ OUTMASK);
 	}
+	if( delayBus ) hd44780_functions->uPause (1);
 
 	// Read inputs
 	readval = ~ port_in (lptPort + 1) ^ INMASK;

server/drivers/hd44780-winamp.c

@@ -138,13 +138,19 @@ lcdwinamp_HD44780_senddata (unsigned char displayID, unsigned char flags, unsign
 	// Output the actual data
 	port_out (lptPort, ch);
 
+	if( delayBus ) hd44780_functions->uPause (1);
+
 	// then set EN high
 	port_out (lptPort + 2, (enableLines|portControl|backlight_bit) ^ OUTMASK);
 
+	if( delayBus ) hd44780_functions->uPause (1);
+
 	// 80 nS setup from valid data to EN low will be met without any delay
 	// unless you are running a REALLY FAST ISA bus (like 75 MHZ!)
 	// 230 nS minimum E high time provided by ISA bus delays as well...
 
+	// ABOVE TEXT ignored now, using delays if delayBus is specified
+
 	// Set EN low and we're done...
 	port_out (lptPort + 2, (portControl|backlight_bit) ^ OUTMASK);
 
@@ -167,6 +173,8 @@ unsigned char lcdwinamp_HD44780_readkeypad (unsigned int YData)
 	port_out (lptPort, ~YData & 0x00FF );
 	port_out (lptPort + 2, ( ((~YData & 0x0100) >> 7) | ((~YData & 0x0200) >> 7 )) ^ OUTMASK);
 
+	if( delayBus ) hd44780_functions->uPause (1);
+
 	// Read inputs
 	readval = ~ port_in (lptPort + 1) ^ INMASK;
 

server/drivers/hd44780.c

@@ -112,11 +112,16 @@ static int numDisplays = 0;
 // input span list but is kept to save some cpu cycles.
 static int *dispSizes = NULL;
 
-// Keypad and backlight option
+// Keypad, backlight extended interface and delay options
 char have_keypad = 0;	 // off by default
 char have_backlight = 0; // off by default
 char extIF = 0;		 // off by default
-			 // These vars is not static, so it's accessable from all sub-drivers
+int delayMult = 1;	 // Delay multiplier for slow displays
+char delayBus = 0;	 // Delay if the computer can send data too fast over
+			 // its bus to LPT port
+
+			 // These vars is not static, so it's accessable from
+			 // all sub-drivers
 			 // Indeed, this should become cleaner...  later...
 
 // Autorepeat values
@@ -193,6 +198,11 @@ HD44780_init (lcd_logical_driver * driver, char *args)
 	//// READ THE CONFIG FILE
 
 	port		= driver->config_get_int( DriverName, "port", 0, 0x278 );
+	extIF		= driver->config_get_bool( DriverName, "extended", 0, 0 );
+	have_keypad	= driver->config_get_bool( DriverName, "keypad", 0, 0 );
+	have_backlight	= driver->config_get_bool( DriverName, "backlight", 0, 0 );
+	delayMult 	= driver->config_get_int( DriverName, "delaymult", 0, 1 );
+	delayBus 	= driver->config_get_bool( DriverName, "delaybus", 0, 0 );
 
 	// Get and search for the connection type
 	s = driver->config_get_string( DriverName, "connectiontype", 0, "4bit" );
@@ -213,10 +223,6 @@ HD44780_init (lcd_logical_driver * driver, char *args)
 		}
 	}
 
-	extIF		= driver->config_get_bool( DriverName, "extended", 0, 0 );
-	have_keypad	= driver->config_get_bool( DriverName, "keypad", 0, 0 );
-	have_backlight	= driver->config_get_bool( DriverName, "backlight", 0, 0 );
-
 	// Get and parse size
 	s = driver->config_get_string( DriverName, "size", 0, "20x4" );
 	if( sscanf( s, "%dx%d", &(driver->wid), &(driver->hgt) ) != 2 ) {
@@ -336,8 +342,10 @@ common_init ()
 // IO delay to avoid a task switch
 //
 void
-uPause (int delayCalls)
+uPause (int usecs)
 {
+	int delay = usecs * delayMult;  // To correct for slower displays
+
 #if defined DELAY_GETTIMEOFDAY
 	struct timeval current_time,delay_time,wait_time;
 
@@ -346,7 +354,7 @@ uPause (int delayCalls)
 
 	// Calculate when delay is over
 	delay_time.tv_sec  = 0;
-	delay_time.tv_usec = delayCalls;
+	delay_time.tv_usec = delay;
 	timeradd(&current_time,&delay_time,&wait_time);
 
 	do {
@@ -354,18 +362,19 @@ uPause (int delayCalls)
 	} while (timercmp(&current_time,&wait_time,<));
 
 #elif defined DELAY_NANOSLEEP
-	struct timespec delay,remaining;
+	struct timespec delay_time,remaining;
 
-	delay.tv_sec = 0;
+	delay_time.tv_sec = 0;
-	delay.tv_nsec = delayCalls * 1000;
+	delay_time.tv_nsec = delay * 1000;
-	while ( nanosleep(&delay,&remaining) == -1 )
+	while ( nanosleep(&delay_time,&remaining) == -1 )
 	{
-		delay.tv_sec  = remaining.tv_sec;
+		delay_time.tv_sec  = remaining.tv_sec;
-		delay.tv_nsec = remaining.tv_nsec;
+		delay_time.tv_nsec = remaining.tv_nsec;
 	}
 #else // using I/O timing
+      // Assuming every call takes 1us (which can be quite incorrect)
 	int i;
-	for (i = 0; i < delayCalls; ++i)
+	for (i = 0; i < delay; ++i)
 		port_in (port);
 #endif
 }

server/drivers/hd44780.h

@@ -24,6 +24,8 @@
 extern char have_keypad;	// non-zero if the keypad code is activated
 extern char have_backlight;	// non-zero if we can control the backlight
 extern char extIF;		// non-zero if we should control > 2 LCDs
+extern char delayBus;		// non-zero if axtra delays for the bus speed
+				// should be inserted.
 
 int HD44780_init (struct lcd_logical_driver *driver, char *args);
 /* The following methods can all be hidden. They are used through function ptrs