mangavalk/lcdproc
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity
Files
2af71ca67335bf57faefca6efbf1efae5f06cb21
lcdproc/server/drivers/hd44780-4bit.c
T

260 lines
7.7 KiB
C
Raw Blame History

/*
* 4-bit driver module for Hitachi HD44780 based LCD displays.
* The LCD is operated in it's 4 bit-mode to be connected to a single
* 8 bit-port.
*
* Copyright (c) 2000, 1999, 1995 Benjamin Tse <blt@Comports.com>
* 2001 Joris Robijn <joris@robijn.net>
* 1999 Andrew McMeikan <andrewm@engineer.com>
* 1998 Richard Rognlie <rrognlie@gamerz.net>
* 1997 Matthias Prinke <m.prinke@trashcan.mcnet.de>
*
* The connections are:
* printer port LCD
* D0 (2) D4 (11)
* D1 (3) D5 (12)
* D2 (4) D6 (13)
* D3 (5) D7 (14)
* D4 (6) RS (4)
* D5 (7) RW (5) (LCD3 - 6) (optional - pull all LCD RW low)
* D6 (8) EN (6)
* D7 (9) EN2 (LCD2 - 6) (optional)
*
* Backlight
* D5 (7) backlight (optional, see documentation)
*
* Extended interface (including LCD3 above)
* D5 (7) EN3
* STR (1) EN4
* LF (14) EN5
* INIT (16) EN6
* SEL (17) EN7
*
* Keypad connection (optional):
* Some diodes and resistors are needed, see further documentation.
* printer port keypad
* D0 (2) Y0
* D1 (3) Y1
* D2 (4) Y2
* D3 (5) Y3
* D4 (6) Y4
* D5 (7) Y5
* nSTRB (1) Y6
* nLF (14) Y7
* INIT (16) Y8
* nSEL (17) Y9
* nACK (10) X0
* BUSY (11) X1
* PAPEREND (12 X2
* SELIN (13) X3
* nFAULT (15) X4
*
* Added support for up to 7 LCDs Jan 2000, Benjamin Tse
* Created modular driver Dec 1999, Benjamin Tse <blt@Comports.com>
*
* Based on Matthias Prinke's <m.prinke@trashcan.mcnet.de> lcd4.c module
* in lcdstat. This was in turn based on Benjamin Tse's lcdtime package
* which uses the LCD controller in its 8-bit mode.
*
* This file is released under the GNU General Public License. Refer to the
* COPYING file distributed with this package.
*/
#include "hd44780-4bit.h"
#include "hd44780-low.h"
#include "lpt-port.h"
#include "port.h"
#include <stdio.h>
#include <string.h>
#include <errno.h>
// Generally, any function that accesses the LCD control lines needs to be
// implemented separately for each HW design. This is typically (but not
// restricted to):
// HD44780_senddata
// HD44780_readkeypad
void lcdstat_HD44780_senddata (PrivateData *p, unsigned char displayID, unsigned char flags, unsigned char ch);
void lcdstat_HD44780_backlight (PrivateData *p, unsigned char state);
unsigned char lcdstat_HD44780_readkeypad (PrivateData *p, unsigned int YData);
#define RS 0x10
#define RW 0x20
#define EN1 0x40
#define EN2 0x80
#define EN3 0x20
#define BL 0x20
// note that the above bits are all meant for the data port of LPT
static const unsigned char EnMask[] = { EN1, EN2, EN3, STRB, LF, INIT, SEL };
#define ALLEXT (STRB|LF|INIT|SEL)
// The above bits are on the control port of LPT
// initialisation function
int
hd_init_4bit (Driver *drvthis)
{
PrivateData *p = (PrivateData*) drvthis->private_data;
HD44780_functions *hd44780_functions = p->hd44780_functions;
int enableLines = EN1 | EN2 | EN3;
// Reserve the port registers
port_access_multiple(p->port,3);
hd44780_functions->senddata = lcdstat_HD44780_senddata;
hd44780_functions->backlight = lcdstat_HD44780_backlight;
hd44780_functions->readkeypad = lcdstat_HD44780_readkeypad;
// powerup the lcd now
port_out (p->port + 2, 0 ^ OUTMASK);
port_out (p->port, 0x03);
if( p->delayBus ) hd44780_functions->uPause (p, 1);
/* We'll now send 0x03 a coulpe of times,
* which is in fact (FUNCSET | IF_8BIT) >> 4 */
port_out (p->port, enableLines | 0x03);
port_out (p->port + 2, ALLEXT ^ OUTMASK);
if( p->delayBus ) hd44780_functions->uPause (p, 1);
port_out (p->port, 0x03);
port_out (p->port + 2, 0 ^ OUTMASK);
hd44780_functions->uPause (p, 15000);
port_out (p->port, enableLines | 0x03);
port_out (p->port + 2, ALLEXT ^ OUTMASK);
if( p->delayBus ) hd44780_functions->uPause (p, 1);
port_out (p->port, 0x03);
port_out (p->port + 2, 0 ^ OUTMASK);
hd44780_functions->uPause (p, 5000);
port_out (p->port, enableLines | 0x03);
port_out (p->port + 2, ALLEXT ^ OUTMASK);
if( p->delayBus ) hd44780_functions->uPause (p, 1);
port_out (p->port, 0x03);
port_out (p->port + 2, 0 ^ OUTMASK);
hd44780_functions->uPause (p, 100);
port_out (p->port, enableLines | 0x03);
port_out (p->port + 2, ALLEXT ^ OUTMASK);
if( p->delayBus ) hd44780_functions->uPause (p, 1);
port_out (p->port, 0x03);
port_out (p->port + 2, 0 ^ OUTMASK);
hd44780_functions->uPause (p, 100);
// now in 8-bit mode... set 4-bit mode
port_out (p->port, 0x02);
if( p->delayBus ) hd44780_functions->uPause (p, 1);
port_out (p->port, enableLines | 0x02);
port_out (p->port + 2, ALLEXT ^ OUTMASK);
if( p->delayBus ) hd44780_functions->uPause (p, 1);
port_out (p->port, 0x02);
port_out (p->port + 2, 0 ^ OUTMASK);
hd44780_functions->uPause (p, 100);
// Set up two-line, small character (5x8) mode
hd44780_functions->senddata (p, 0, RS_INSTR, FUNCSET | IF_4BIT | TWOLINE | SMALLCHAR );
hd44780_functions->uPause (p, 40);
common_init (p, IF_4BIT);
if (p->have_keypad) {
// Remember which input lines are stuck
p->stuckinputs = lcdstat_HD44780_readkeypad (p, 0);
}
return 0;
}
// lcdstat_HD44780_senddata
void
lcdstat_HD44780_senddata (PrivateData *p, unsigned char displayID, unsigned char flags, unsigned char ch)
{
unsigned char enableLines = 0, portControl = 0;
unsigned char h = (ch >> 4) & 0x0f; // high and low nibbles
unsigned char l = ch & 0x0f;
if (flags == RS_INSTR)
portControl = 0;
else //if (flags == RS_DATA)
portControl = RS;
portControl |= p->backlight_bit;
if (displayID <= 3) {
if (displayID == 0) {
enableLines = EnMask[0] | EnMask[1] | EnMask[2];
} else {
enableLines = EnMask[displayID - 1];
}
port_out (p->port, portControl | h);
if( p->delayBus ) p->hd44780_functions->uPause (p, 1);
port_out (p->port, enableLines | portControl | h);
if( p->delayBus ) p->hd44780_functions->uPause (p, 1);
port_out (p->port, portControl | h);
port_out (p->port, portControl | l);
if( p->delayBus ) p->hd44780_functions->uPause (p, 1);
port_out (p->port, enableLines | portControl | l);
if( p->delayBus ) p->hd44780_functions->uPause (p, 1);
port_out (p->port, portControl | l);
}
if (p->numDisplays > 3) {
if (displayID == 0) {
enableLines = ALLEXT;
} else {
enableLines = EnMask[(displayID - 1)];
}
port_out (p->port, portControl | h);
if( p->delayBus ) p->hd44780_functions->uPause (p, 1);
port_out (p->port + 2, enableLines ^ OUTMASK);
if( p->delayBus ) p->hd44780_functions->uPause (p, 1);
port_out (p->port + 2, 0 ^ OUTMASK);
port_out (p->port, portControl | l);
if( p->delayBus ) p->hd44780_functions->uPause (p, 1);
port_out (p->port + 2, enableLines ^ OUTMASK);
if( p->delayBus ) p->hd44780_functions->uPause (p, 1);
port_out (p->port + 2, 0 ^ OUTMASK);
}
}
void lcdstat_HD44780_backlight (PrivateData *p, unsigned char state)
{
p->backlight_bit = ((!p->have_backlight||state)?0:BL);
port_out (p->port, p->backlight_bit);
}
unsigned char lcdstat_HD44780_readkeypad (PrivateData *p, unsigned int YData)
{
unsigned char readval;
// 10 bits output or 6 bits if >=3 displays
// Convert the positive logic to the negative logic on the LPT port
port_out (p->port, ~YData & 0x003F );
if (p->numDisplays<=3) {
// Can't combine >3 displays with >6 keypad output lines
port_out (p->port + 2, ( ((~YData & 0x03C0) << 6 )) ^ OUTMASK);
}
if( p->delayBus ) p->hd44780_functions->uPause (p, 1);
// Read inputs
readval = ~ port_in (p->port + 1) ^ INMASK;
// Put port back into idle state for backlight
port_out (p->port, p->backlight_bit);
// And convert value back (MSB first).
return (((readval & FAULT) / FAULT <<4) | /* pin 15 */
((readval & SELIN) / SELIN <<3) | /* pin 13 */
((readval & PAPEREND) / PAPEREND <<2) | /* pin 12 */
((readval & BUSY) / BUSY <<1) | /* pin 11 */
((readval & ACK) / ACK )) & ~p->stuckinputs; /* pin 10 */
}
Reference in New Issue View Git Blame Copy Permalink